[chore] update otel libraries (#3740)

* chore: update otel dependencies

* refactor: combine tracing & metrics in observability package

* chore: update example tracing compose file

vendor/go.opentelemetry.io/auto/sdk/CONTRIBUTING.md

@@ -0,0 +1,27 @@
+# Contributing to go.opentelemetry.io/auto/sdk
+
+The `go.opentelemetry.io/auto/sdk` module is a purpose built OpenTelemetry SDK.
+It is designed to be:
+
+0. An OpenTelemetry compliant SDK
+1. Instrumented by auto-instrumentation (serializable into OTLP JSON)
+2. Lightweight
+3. User-friendly
+
+These design choices are listed in the order of their importance.
+
+The primary design goal of this module is to be an OpenTelemetry SDK.
+This means that it needs to implement the Go APIs found in `go.opentelemetry.io/otel`.
+
+Having met the requirement of SDK compliance, this module needs to provide code that the `go.opentelemetry.io/auto` module can instrument.
+The chosen approach to meet this goal is to ensure the telemetry from the SDK is serializable into JSON encoded OTLP.
+This ensures then that the serialized form is compatible with other OpenTelemetry systems, and the auto-instrumentation can use these systems to deserialize any telemetry it is sent.
+
+Outside of these first two goals, the intended use becomes relevant.
+This package is intended to be used in the `go.opentelemetry.io/otel` global API as a default when the auto-instrumentation is running.
+Because of this, this package needs to not add unnecessary dependencies to that API.
+Ideally, it adds none.
+It also needs to operate efficiently.
+
+Finally, this module is designed to be user-friendly to Go development.
+It hides complexity in order to provide simpler APIs when the previous goals can all still be met.

vendor/go.opentelemetry.io/auto/sdk/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/go.opentelemetry.io/auto/sdk/VERSIONING.md

@@ -0,0 +1,15 @@
+# Versioning
+
+This document describes the versioning policy for this module.
+This policy is designed so the following goals can be achieved.
+
+**Users are provided a codebase of value that is stable and secure.**
+
+## Policy
+
+* Versioning of this module will be idiomatic of a Go project using [Go modules](https://github.com/golang/go/wiki/Modules).
+  * [Semantic import versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning) will be used.
+    * Versions will comply with [semver 2.0](https://semver.org/spec/v2.0.0.html).
+    * Any `v2` or higher version of this module will be included as a `/vN` at the end of the module path used in `go.mod` files and in the package import path.
+
+* GitHub releases will be made for all releases.

vendor/go.opentelemetry.io/auto/sdk/doc.go

@@ -0,0 +1,14 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+/*
+Package sdk provides an auto-instrumentable OpenTelemetry SDK.
+
+An [go.opentelemetry.io/auto.Instrumentation] can be configured to target the
+process running this SDK. In that case, all telemetry the SDK produces will be
+processed and handled by that [go.opentelemetry.io/auto.Instrumentation].
+
+By default, if there is no [go.opentelemetry.io/auto.Instrumentation] set to
+auto-instrument the SDK, the SDK will not generate any telemetry.
+*/
+package sdk

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/attr.go

@@ -0,0 +1,58 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+// Attr is a key-value pair.
+type Attr struct {
+	Key   string `json:"key,omitempty"`
+	Value Value  `json:"value,omitempty"`
+}
+
+// String returns an Attr for a string value.
+func String(key, value string) Attr {
+	return Attr{key, StringValue(value)}
+}
+
+// Int64 returns an Attr for an int64 value.
+func Int64(key string, value int64) Attr {
+	return Attr{key, Int64Value(value)}
+}
+
+// Int returns an Attr for an int value.
+func Int(key string, value int) Attr {
+	return Int64(key, int64(value))
+}
+
+// Float64 returns an Attr for a float64 value.
+func Float64(key string, value float64) Attr {
+	return Attr{key, Float64Value(value)}
+}
+
+// Bool returns an Attr for a bool value.
+func Bool(key string, value bool) Attr {
+	return Attr{key, BoolValue(value)}
+}
+
+// Bytes returns an Attr for a []byte value.
+// The passed slice must not be changed after it is passed.
+func Bytes(key string, value []byte) Attr {
+	return Attr{key, BytesValue(value)}
+}
+
+// Slice returns an Attr for a []Value value.
+// The passed slice must not be changed after it is passed.
+func Slice(key string, value ...Value) Attr {
+	return Attr{key, SliceValue(value...)}
+}
+
+// Map returns an Attr for a map value.
+// The passed slice must not be changed after it is passed.
+func Map(key string, value ...Attr) Attr {
+	return Attr{key, MapValue(value...)}
+}
+
+// Equal returns if a is equal to b.
+func (a Attr) Equal(b Attr) bool {
+	return a.Key == b.Key && a.Value.Equal(b.Value)
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/doc.go

@@ -0,0 +1,8 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+/*
+Package telemetry provides a lightweight representations of OpenTelemetry
+telemetry that is compatible with the OTLP JSON protobuf encoding.
+*/
+package telemetry

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/id.go

@@ -0,0 +1,103 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"encoding/hex"
+	"errors"
+	"fmt"
+)
+
+const (
+	traceIDSize = 16
+	spanIDSize  = 8
+)
+
+// TraceID is a custom data type that is used for all trace IDs.
+type TraceID [traceIDSize]byte
+
+// String returns the hex string representation form of a TraceID.
+func (tid TraceID) String() string {
+	return hex.EncodeToString(tid[:])
+}
+
+// IsEmpty returns false if id contains at least one non-zero byte.
+func (tid TraceID) IsEmpty() bool {
+	return tid == [traceIDSize]byte{}
+}
+
+// MarshalJSON converts the trace ID into a hex string enclosed in quotes.
+func (tid TraceID) MarshalJSON() ([]byte, error) {
+	if tid.IsEmpty() {
+		return []byte(`""`), nil
+	}
+	return marshalJSON(tid[:])
+}
+
+// UnmarshalJSON inflates the trace ID from hex string, possibly enclosed in
+// quotes.
+func (tid *TraceID) UnmarshalJSON(data []byte) error {
+	*tid = [traceIDSize]byte{}
+	return unmarshalJSON(tid[:], data)
+}
+
+// SpanID is a custom data type that is used for all span IDs.
+type SpanID [spanIDSize]byte
+
+// String returns the hex string representation form of a SpanID.
+func (sid SpanID) String() string {
+	return hex.EncodeToString(sid[:])
+}
+
+// IsEmpty returns true if the span ID contains at least one non-zero byte.
+func (sid SpanID) IsEmpty() bool {
+	return sid == [spanIDSize]byte{}
+}
+
+// MarshalJSON converts span ID into a hex string enclosed in quotes.
+func (sid SpanID) MarshalJSON() ([]byte, error) {
+	if sid.IsEmpty() {
+		return []byte(`""`), nil
+	}
+	return marshalJSON(sid[:])
+}
+
+// UnmarshalJSON decodes span ID from hex string, possibly enclosed in quotes.
+func (sid *SpanID) UnmarshalJSON(data []byte) error {
+	*sid = [spanIDSize]byte{}
+	return unmarshalJSON(sid[:], data)
+}
+
+// marshalJSON converts id into a hex string enclosed in quotes.
+func marshalJSON(id []byte) ([]byte, error) {
+	// Plus 2 quote chars at the start and end.
+	hexLen := hex.EncodedLen(len(id)) + 2
+
+	b := make([]byte, hexLen)
+	hex.Encode(b[1:hexLen-1], id)
+	b[0], b[hexLen-1] = '"', '"'
+
+	return b, nil
+}
+
+// unmarshalJSON inflates trace id from hex string, possibly enclosed in quotes.
+func unmarshalJSON(dst []byte, src []byte) error {
+	if l := len(src); l >= 2 && src[0] == '"' && src[l-1] == '"' {
+		src = src[1 : l-1]
+	}
+	nLen := len(src)
+	if nLen == 0 {
+		return nil
+	}
+
+	if len(dst) != hex.DecodedLen(nLen) {
+		return errors.New("invalid length for ID")
+	}
+
+	_, err := hex.Decode(dst, src)
+	if err != nil {
+		return fmt.Errorf("cannot unmarshal ID from string '%s': %w", string(src), err)
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/number.go

@@ -0,0 +1,67 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"encoding/json"
+	"strconv"
+)
+
+// protoInt64 represents the protobuf encoding of integers which can be either
+// strings or integers.
+type protoInt64 int64
+
+// Int64 returns the protoInt64 as an int64.
+func (i *protoInt64) Int64() int64 { return int64(*i) }
+
+// UnmarshalJSON decodes both strings and integers.
+func (i *protoInt64) UnmarshalJSON(data []byte) error {
+	if data[0] == '"' {
+		var str string
+		if err := json.Unmarshal(data, &str); err != nil {
+			return err
+		}
+		parsedInt, err := strconv.ParseInt(str, 10, 64)
+		if err != nil {
+			return err
+		}
+		*i = protoInt64(parsedInt)
+	} else {
+		var parsedInt int64
+		if err := json.Unmarshal(data, &parsedInt); err != nil {
+			return err
+		}
+		*i = protoInt64(parsedInt)
+	}
+	return nil
+}
+
+// protoUint64 represents the protobuf encoding of integers which can be either
+// strings or integers.
+type protoUint64 uint64
+
+// Int64 returns the protoUint64 as a uint64.
+func (i *protoUint64) Uint64() uint64 { return uint64(*i) }
+
+// UnmarshalJSON decodes both strings and integers.
+func (i *protoUint64) UnmarshalJSON(data []byte) error {
+	if data[0] == '"' {
+		var str string
+		if err := json.Unmarshal(data, &str); err != nil {
+			return err
+		}
+		parsedUint, err := strconv.ParseUint(str, 10, 64)
+		if err != nil {
+			return err
+		}
+		*i = protoUint64(parsedUint)
+	} else {
+		var parsedUint uint64
+		if err := json.Unmarshal(data, &parsedUint); err != nil {
+			return err
+		}
+		*i = protoUint64(parsedUint)
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/resource.go

@@ -0,0 +1,66 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+)
+
+// Resource information.
+type Resource struct {
+	// Attrs are the set of attributes that describe the resource. Attribute
+	// keys MUST be unique (it is not allowed to have more than one attribute
+	// with the same key).
+	Attrs []Attr `json:"attributes,omitempty"`
+	// DroppedAttrs is the number of dropped attributes. If the value
+	// is 0, then no attributes were dropped.
+	DroppedAttrs uint32 `json:"droppedAttributesCount,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into r.
+func (r *Resource) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid Resource type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid Resource field: %#v", keyIface)
+		}
+
+		switch key {
+		case "attributes":
+			err = decoder.Decode(&r.Attrs)
+		case "droppedAttributesCount", "dropped_attributes_count":
+			err = decoder.Decode(&r.DroppedAttrs)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/scope.go

@@ -0,0 +1,67 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+)
+
+// Scope is the identifying values of the instrumentation scope.
+type Scope struct {
+	Name         string `json:"name,omitempty"`
+	Version      string `json:"version,omitempty"`
+	Attrs        []Attr `json:"attributes,omitempty"`
+	DroppedAttrs uint32 `json:"droppedAttributesCount,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into r.
+func (s *Scope) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid Scope type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid Scope field: %#v", keyIface)
+		}
+
+		switch key {
+		case "name":
+			err = decoder.Decode(&s.Name)
+		case "version":
+			err = decoder.Decode(&s.Version)
+		case "attributes":
+			err = decoder.Decode(&s.Attrs)
+		case "droppedAttributesCount", "dropped_attributes_count":
+			err = decoder.Decode(&s.DroppedAttrs)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/span.go

@@ -0,0 +1,456 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"bytes"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"time"
+)
+
+// A Span represents a single operation performed by a single component of the
+// system.
+type Span struct {
+	// A unique identifier for a trace. All spans from the same trace share
+	// the same `trace_id`. The ID is a 16-byte array. An ID with all zeroes OR
+	// of length other than 16 bytes is considered invalid (empty string in OTLP/JSON
+	// is zero-length and thus is also invalid).
+	//
+	// This field is required.
+	TraceID TraceID `json:"traceId,omitempty"`
+	// A unique identifier for a span within a trace, assigned when the span
+	// is created. The ID is an 8-byte array. An ID with all zeroes OR of length
+	// other than 8 bytes is considered invalid (empty string in OTLP/JSON
+	// is zero-length and thus is also invalid).
+	//
+	// This field is required.
+	SpanID SpanID `json:"spanId,omitempty"`
+	// trace_state conveys information about request position in multiple distributed tracing graphs.
+	// It is a trace_state in w3c-trace-context format: https://www.w3.org/TR/trace-context/#tracestate-header
+	// See also https://github.com/w3c/distributed-tracing for more details about this field.
+	TraceState string `json:"traceState,omitempty"`
+	// The `span_id` of this span's parent span. If this is a root span, then this
+	// field must be empty. The ID is an 8-byte array.
+	ParentSpanID SpanID `json:"parentSpanId,omitempty"`
+	// Flags, a bit field.
+	//
+	// Bits 0-7 (8 least significant bits) are the trace flags as defined in W3C Trace
+	// Context specification. To read the 8-bit W3C trace flag, use
+	// `flags & SPAN_FLAGS_TRACE_FLAGS_MASK`.
+	//
+	// See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
+	//
+	// Bits 8 and 9 represent the 3 states of whether a span's parent
+	// is remote. The states are (unknown, is not remote, is remote).
+	// To read whether the value is known, use `(flags & SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK) != 0`.
+	// To read whether the span is remote, use `(flags & SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK) != 0`.
+	//
+	// When creating span messages, if the message is logically forwarded from another source
+	// with an equivalent flags fields (i.e., usually another OTLP span message), the field SHOULD
+	// be copied as-is. If creating from a source that does not have an equivalent flags field
+	// (such as a runtime representation of an OpenTelemetry span), the high 22 bits MUST
+	// be set to zero.
+	// Readers MUST NOT assume that bits 10-31 (22 most significant bits) will be zero.
+	//
+	// [Optional].
+	Flags uint32 `json:"flags,omitempty"`
+	// A description of the span's operation.
+	//
+	// For example, the name can be a qualified method name or a file name
+	// and a line number where the operation is called. A best practice is to use
+	// the same display name at the same call point in an application.
+	// This makes it easier to correlate spans in different traces.
+	//
+	// This field is semantically required to be set to non-empty string.
+	// Empty value is equivalent to an unknown span name.
+	//
+	// This field is required.
+	Name string `json:"name"`
+	// Distinguishes between spans generated in a particular context. For example,
+	// two spans with the same name may be distinguished using `CLIENT` (caller)
+	// and `SERVER` (callee) to identify queueing latency associated with the span.
+	Kind SpanKind `json:"kind,omitempty"`
+	// start_time_unix_nano is the start time of the span. On the client side, this is the time
+	// kept by the local machine where the span execution starts. On the server side, this
+	// is the time when the server's application handler starts running.
+	// Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
+	//
+	// This field is semantically required and it is expected that end_time >= start_time.
+	StartTime time.Time `json:"startTimeUnixNano,omitempty"`
+	// end_time_unix_nano is the end time of the span. On the client side, this is the time
+	// kept by the local machine where the span execution ends. On the server side, this
+	// is the time when the server application handler stops running.
+	// Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
+	//
+	// This field is semantically required and it is expected that end_time >= start_time.
+	EndTime time.Time `json:"endTimeUnixNano,omitempty"`
+	// attributes is a collection of key/value pairs. Note, global attributes
+	// like server name can be set using the resource API. Examples of attributes:
+	//
+	//     "/http/user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36"
+	//     "/http/server_latency": 300
+	//     "example.com/myattribute": true
+	//     "example.com/score": 10.239
+	//
+	// The OpenTelemetry API specification further restricts the allowed value types:
+	// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/common/README.md#attribute
+	// Attribute keys MUST be unique (it is not allowed to have more than one
+	// attribute with the same key).
+	Attrs []Attr `json:"attributes,omitempty"`
+	// dropped_attributes_count is the number of attributes that were discarded. Attributes
+	// can be discarded because their keys are too long or because there are too many
+	// attributes. If this value is 0, then no attributes were dropped.
+	DroppedAttrs uint32 `json:"droppedAttributesCount,omitempty"`
+	// events is a collection of Event items.
+	Events []*SpanEvent `json:"events,omitempty"`
+	// dropped_events_count is the number of dropped events. If the value is 0, then no
+	// events were dropped.
+	DroppedEvents uint32 `json:"droppedEventsCount,omitempty"`
+	// links is a collection of Links, which are references from this span to a span
+	// in the same or different trace.
+	Links []*SpanLink `json:"links,omitempty"`
+	// dropped_links_count is the number of dropped links after the maximum size was
+	// enforced. If this value is 0, then no links were dropped.
+	DroppedLinks uint32 `json:"droppedLinksCount,omitempty"`
+	// An optional final status for this span. Semantically when Status isn't set, it means
+	// span's status code is unset, i.e. assume STATUS_CODE_UNSET (code = 0).
+	Status *Status `json:"status,omitempty"`
+}
+
+// MarshalJSON encodes s into OTLP formatted JSON.
+func (s Span) MarshalJSON() ([]byte, error) {
+	startT := s.StartTime.UnixNano()
+	if s.StartTime.IsZero() || startT < 0 {
+		startT = 0
+	}
+
+	endT := s.EndTime.UnixNano()
+	if s.EndTime.IsZero() || endT < 0 {
+		endT = 0
+	}
+
+	// Override non-empty default SpanID marshal and omitempty.
+	var parentSpanId string
+	if !s.ParentSpanID.IsEmpty() {
+		b := make([]byte, hex.EncodedLen(spanIDSize))
+		hex.Encode(b, s.ParentSpanID[:])
+		parentSpanId = string(b)
+	}
+
+	type Alias Span
+	return json.Marshal(struct {
+		Alias
+		ParentSpanID string `json:"parentSpanId,omitempty"`
+		StartTime    uint64 `json:"startTimeUnixNano,omitempty"`
+		EndTime      uint64 `json:"endTimeUnixNano,omitempty"`
+	}{
+		Alias:        Alias(s),
+		ParentSpanID: parentSpanId,
+		StartTime:    uint64(startT),
+		EndTime:      uint64(endT),
+	})
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into s.
+func (s *Span) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid Span type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid Span field: %#v", keyIface)
+		}
+
+		switch key {
+		case "traceId", "trace_id":
+			err = decoder.Decode(&s.TraceID)
+		case "spanId", "span_id":
+			err = decoder.Decode(&s.SpanID)
+		case "traceState", "trace_state":
+			err = decoder.Decode(&s.TraceState)
+		case "parentSpanId", "parent_span_id":
+			err = decoder.Decode(&s.ParentSpanID)
+		case "flags":
+			err = decoder.Decode(&s.Flags)
+		case "name":
+			err = decoder.Decode(&s.Name)
+		case "kind":
+			err = decoder.Decode(&s.Kind)
+		case "startTimeUnixNano", "start_time_unix_nano":
+			var val protoUint64
+			err = decoder.Decode(&val)
+			s.StartTime = time.Unix(0, int64(val.Uint64()))
+		case "endTimeUnixNano", "end_time_unix_nano":
+			var val protoUint64
+			err = decoder.Decode(&val)
+			s.EndTime = time.Unix(0, int64(val.Uint64()))
+		case "attributes":
+			err = decoder.Decode(&s.Attrs)
+		case "droppedAttributesCount", "dropped_attributes_count":
+			err = decoder.Decode(&s.DroppedAttrs)
+		case "events":
+			err = decoder.Decode(&s.Events)
+		case "droppedEventsCount", "dropped_events_count":
+			err = decoder.Decode(&s.DroppedEvents)
+		case "links":
+			err = decoder.Decode(&s.Links)
+		case "droppedLinksCount", "dropped_links_count":
+			err = decoder.Decode(&s.DroppedLinks)
+		case "status":
+			err = decoder.Decode(&s.Status)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SpanFlags represents constants used to interpret the
+// Span.flags field, which is protobuf 'fixed32' type and is to
+// be used as bit-fields. Each non-zero value defined in this enum is
+// a bit-mask.  To extract the bit-field, for example, use an
+// expression like:
+//
+//	(span.flags & SPAN_FLAGS_TRACE_FLAGS_MASK)
+//
+// See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
+//
+// Note that Span flags were introduced in version 1.1 of the
+// OpenTelemetry protocol.  Older Span producers do not set this
+// field, consequently consumers should not rely on the absence of a
+// particular flag bit to indicate the presence of a particular feature.
+type SpanFlags int32
+
+const (
+	// Bits 0-7 are used for trace flags.
+	SpanFlagsTraceFlagsMask SpanFlags = 255
+	// Bits 8 and 9 are used to indicate that the parent span or link span is remote.
+	// Bit 8 (`HAS_IS_REMOTE`) indicates whether the value is known.
+	// Bit 9 (`IS_REMOTE`) indicates whether the span or link is remote.
+	SpanFlagsContextHasIsRemoteMask SpanFlags = 256
+	// SpanFlagsContextHasIsRemoteMask indicates the Span is remote.
+	SpanFlagsContextIsRemoteMask SpanFlags = 512
+)
+
+// SpanKind is the type of span. Can be used to specify additional relationships between spans
+// in addition to a parent/child relationship.
+type SpanKind int32
+
+const (
+	// Indicates that the span represents an internal operation within an application,
+	// as opposed to an operation happening at the boundaries. Default value.
+	SpanKindInternal SpanKind = 1
+	// Indicates that the span covers server-side handling of an RPC or other
+	// remote network request.
+	SpanKindServer SpanKind = 2
+	// Indicates that the span describes a request to some remote service.
+	SpanKindClient SpanKind = 3
+	// Indicates that the span describes a producer sending a message to a broker.
+	// Unlike CLIENT and SERVER, there is often no direct critical path latency relationship
+	// between producer and consumer spans. A PRODUCER span ends when the message was accepted
+	// by the broker while the logical processing of the message might span a much longer time.
+	SpanKindProducer SpanKind = 4
+	// Indicates that the span describes consumer receiving a message from a broker.
+	// Like the PRODUCER kind, there is often no direct critical path latency relationship
+	// between producer and consumer spans.
+	SpanKindConsumer SpanKind = 5
+)
+
+// Event is a time-stamped annotation of the span, consisting of user-supplied
+// text description and key-value pairs.
+type SpanEvent struct {
+	// time_unix_nano is the time the event occurred.
+	Time time.Time `json:"timeUnixNano,omitempty"`
+	// name of the event.
+	// This field is semantically required to be set to non-empty string.
+	Name string `json:"name,omitempty"`
+	// attributes is a collection of attribute key/value pairs on the event.
+	// Attribute keys MUST be unique (it is not allowed to have more than one
+	// attribute with the same key).
+	Attrs []Attr `json:"attributes,omitempty"`
+	// dropped_attributes_count is the number of dropped attributes. If the value is 0,
+	// then no attributes were dropped.
+	DroppedAttrs uint32 `json:"droppedAttributesCount,omitempty"`
+}
+
+// MarshalJSON encodes e into OTLP formatted JSON.
+func (e SpanEvent) MarshalJSON() ([]byte, error) {
+	t := e.Time.UnixNano()
+	if e.Time.IsZero() || t < 0 {
+		t = 0
+	}
+
+	type Alias SpanEvent
+	return json.Marshal(struct {
+		Alias
+		Time uint64 `json:"timeUnixNano,omitempty"`
+	}{
+		Alias: Alias(e),
+		Time:  uint64(t),
+	})
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into se.
+func (se *SpanEvent) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid SpanEvent type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid SpanEvent field: %#v", keyIface)
+		}
+
+		switch key {
+		case "timeUnixNano", "time_unix_nano":
+			var val protoUint64
+			err = decoder.Decode(&val)
+			se.Time = time.Unix(0, int64(val.Uint64()))
+		case "name":
+			err = decoder.Decode(&se.Name)
+		case "attributes":
+			err = decoder.Decode(&se.Attrs)
+		case "droppedAttributesCount", "dropped_attributes_count":
+			err = decoder.Decode(&se.DroppedAttrs)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// A pointer from the current span to another span in the same trace or in a
+// different trace. For example, this can be used in batching operations,
+// where a single batch handler processes multiple requests from different
+// traces or when the handler receives a request from a different project.
+type SpanLink struct {
+	// A unique identifier of a trace that this linked span is part of. The ID is a
+	// 16-byte array.
+	TraceID TraceID `json:"traceId,omitempty"`
+	// A unique identifier for the linked span. The ID is an 8-byte array.
+	SpanID SpanID `json:"spanId,omitempty"`
+	// The trace_state associated with the link.
+	TraceState string `json:"traceState,omitempty"`
+	// attributes is a collection of attribute key/value pairs on the link.
+	// Attribute keys MUST be unique (it is not allowed to have more than one
+	// attribute with the same key).
+	Attrs []Attr `json:"attributes,omitempty"`
+	// dropped_attributes_count is the number of dropped attributes. If the value is 0,
+	// then no attributes were dropped.
+	DroppedAttrs uint32 `json:"droppedAttributesCount,omitempty"`
+	// Flags, a bit field.
+	//
+	// Bits 0-7 (8 least significant bits) are the trace flags as defined in W3C Trace
+	// Context specification. To read the 8-bit W3C trace flag, use
+	// `flags & SPAN_FLAGS_TRACE_FLAGS_MASK`.
+	//
+	// See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
+	//
+	// Bits 8 and 9 represent the 3 states of whether the link is remote.
+	// The states are (unknown, is not remote, is remote).
+	// To read whether the value is known, use `(flags & SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK) != 0`.
+	// To read whether the link is remote, use `(flags & SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK) != 0`.
+	//
+	// Readers MUST NOT assume that bits 10-31 (22 most significant bits) will be zero.
+	// When creating new spans, bits 10-31 (most-significant 22-bits) MUST be zero.
+	//
+	// [Optional].
+	Flags uint32 `json:"flags,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into sl.
+func (sl *SpanLink) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid SpanLink type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid SpanLink field: %#v", keyIface)
+		}
+
+		switch key {
+		case "traceId", "trace_id":
+			err = decoder.Decode(&sl.TraceID)
+		case "spanId", "span_id":
+			err = decoder.Decode(&sl.SpanID)
+		case "traceState", "trace_state":
+			err = decoder.Decode(&sl.TraceState)
+		case "attributes":
+			err = decoder.Decode(&sl.Attrs)
+		case "droppedAttributesCount", "dropped_attributes_count":
+			err = decoder.Decode(&sl.DroppedAttrs)
+		case "flags":
+			err = decoder.Decode(&sl.Flags)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/status.go

@@ -0,0 +1,40 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+// For the semantics of status codes see
+// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/api.md#set-status
+type StatusCode int32
+
+const (
+	// The default status.
+	StatusCodeUnset StatusCode = 0
+	// The Span has been validated by an Application developer or Operator to
+	// have completed successfully.
+	StatusCodeOK StatusCode = 1
+	// The Span contains an error.
+	StatusCodeError StatusCode = 2
+)
+
+var statusCodeStrings = []string{
+	"Unset",
+	"OK",
+	"Error",
+}
+
+func (s StatusCode) String() string {
+	if s >= 0 && int(s) < len(statusCodeStrings) {
+		return statusCodeStrings[s]
+	}
+	return "<unknown telemetry.StatusCode>"
+}
+
+// The Status type defines a logical error model that is suitable for different
+// programming environments, including REST APIs and RPC APIs.
+type Status struct {
+	// A developer-facing human readable error message.
+	Message string `json:"message,omitempty"`
+	// The status code.
+	Code StatusCode `json:"code,omitempty"`
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/traces.go

@@ -0,0 +1,189 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package telemetry
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+)
+
+// Traces represents the traces data that can be stored in a persistent storage,
+// OR can be embedded by other protocols that transfer OTLP traces data but do
+// not implement the OTLP protocol.
+//
+// The main difference between this message and collector protocol is that
+// in this message there will not be any "control" or "metadata" specific to
+// OTLP protocol.
+//
+// When new fields are added into this message, the OTLP request MUST be updated
+// as well.
+type Traces struct {
+	// An array of ResourceSpans.
+	// For data coming from a single resource this array will typically contain
+	// one element. Intermediary nodes that receive data from multiple origins
+	// typically batch the data before forwarding further and in that case this
+	// array will contain multiple elements.
+	ResourceSpans []*ResourceSpans `json:"resourceSpans,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into td.
+func (td *Traces) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid TracesData type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid TracesData field: %#v", keyIface)
+		}
+
+		switch key {
+		case "resourceSpans", "resource_spans":
+			err = decoder.Decode(&td.ResourceSpans)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// A collection of ScopeSpans from a Resource.
+type ResourceSpans struct {
+	// The resource for the spans in this message.
+	// If this field is not set then no resource info is known.
+	Resource Resource `json:"resource"`
+	// A list of ScopeSpans that originate from a resource.
+	ScopeSpans []*ScopeSpans `json:"scopeSpans,omitempty"`
+	// This schema_url applies to the data in the "resource" field. It does not apply
+	// to the data in the "scope_spans" field which have their own schema_url field.
+	SchemaURL string `json:"schemaUrl,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into rs.
+func (rs *ResourceSpans) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid ResourceSpans type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid ResourceSpans field: %#v", keyIface)
+		}
+
+		switch key {
+		case "resource":
+			err = decoder.Decode(&rs.Resource)
+		case "scopeSpans", "scope_spans":
+			err = decoder.Decode(&rs.ScopeSpans)
+		case "schemaUrl", "schema_url":
+			err = decoder.Decode(&rs.SchemaURL)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// A collection of Spans produced by an InstrumentationScope.
+type ScopeSpans struct {
+	// The instrumentation scope information for the spans in this message.
+	// Semantically when InstrumentationScope isn't set, it is equivalent with
+	// an empty instrumentation scope name (unknown).
+	Scope *Scope `json:"scope"`
+	// A list of Spans that originate from an instrumentation scope.
+	Spans []*Span `json:"spans,omitempty"`
+	// The Schema URL, if known. This is the identifier of the Schema that the span data
+	// is recorded in. To learn more about Schema URL see
+	// https://opentelemetry.io/docs/specs/otel/schemas/#schema-url
+	// This schema_url applies to all spans and span events in the "spans" field.
+	SchemaURL string `json:"schemaUrl,omitempty"`
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into ss.
+func (ss *ScopeSpans) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid ScopeSpans type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid ScopeSpans field: %#v", keyIface)
+		}
+
+		switch key {
+		case "scope":
+			err = decoder.Decode(&ss.Scope)
+		case "spans":
+			err = decoder.Decode(&ss.Spans)
+		case "schemaUrl", "schema_url":
+			err = decoder.Decode(&ss.SchemaURL)
+		default:
+			// Skip unknown.
+		}
+
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/internal/telemetry/value.go

@@ -0,0 +1,452 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+//go:generate stringer -type=ValueKind -trimprefix=ValueKind
+
+package telemetry
+
+import (
+	"bytes"
+	"cmp"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"slices"
+	"strconv"
+	"unsafe"
+)
+
+// A Value represents a structured value.
+// A zero value is valid and represents an empty value.
+type Value struct {
+	// Ensure forward compatibility by explicitly making this not comparable.
+	noCmp [0]func() //nolint: unused  // This is indeed used.
+
+	// num holds the value for Int64, Float64, and Bool. It holds the length
+	// for String, Bytes, Slice, Map.
+	num uint64
+	// any holds either the KindBool, KindInt64, KindFloat64, stringptr,
+	// bytesptr, sliceptr, or mapptr. If KindBool, KindInt64, or KindFloat64
+	// then the value of Value is in num as described above. Otherwise, it
+	// contains the value wrapped in the appropriate type.
+	any any
+}
+
+type (
+	// sliceptr represents a value in Value.any for KindString Values.
+	stringptr *byte
+	// bytesptr represents a value in Value.any for KindBytes Values.
+	bytesptr *byte
+	// sliceptr represents a value in Value.any for KindSlice Values.
+	sliceptr *Value
+	// mapptr represents a value in Value.any for KindMap Values.
+	mapptr *Attr
+)
+
+// ValueKind is the kind of a [Value].
+type ValueKind int
+
+// ValueKind values.
+const (
+	ValueKindEmpty ValueKind = iota
+	ValueKindBool
+	ValueKindFloat64
+	ValueKindInt64
+	ValueKindString
+	ValueKindBytes
+	ValueKindSlice
+	ValueKindMap
+)
+
+var valueKindStrings = []string{
+	"Empty",
+	"Bool",
+	"Float64",
+	"Int64",
+	"String",
+	"Bytes",
+	"Slice",
+	"Map",
+}
+
+func (k ValueKind) String() string {
+	if k >= 0 && int(k) < len(valueKindStrings) {
+		return valueKindStrings[k]
+	}
+	return "<unknown telemetry.ValueKind>"
+}
+
+// StringValue returns a new [Value] for a string.
+func StringValue(v string) Value {
+	return Value{
+		num: uint64(len(v)),
+		any: stringptr(unsafe.StringData(v)),
+	}
+}
+
+// IntValue returns a [Value] for an int.
+func IntValue(v int) Value { return Int64Value(int64(v)) }
+
+// Int64Value returns a [Value] for an int64.
+func Int64Value(v int64) Value {
+	return Value{num: uint64(v), any: ValueKindInt64}
+}
+
+// Float64Value returns a [Value] for a float64.
+func Float64Value(v float64) Value {
+	return Value{num: math.Float64bits(v), any: ValueKindFloat64}
+}
+
+// BoolValue returns a [Value] for a bool.
+func BoolValue(v bool) Value { //nolint:revive // Not a control flag.
+	var n uint64
+	if v {
+		n = 1
+	}
+	return Value{num: n, any: ValueKindBool}
+}
+
+// BytesValue returns a [Value] for a byte slice. The passed slice must not be
+// changed after it is passed.
+func BytesValue(v []byte) Value {
+	return Value{
+		num: uint64(len(v)),
+		any: bytesptr(unsafe.SliceData(v)),
+	}
+}
+
+// SliceValue returns a [Value] for a slice of [Value]. The passed slice must
+// not be changed after it is passed.
+func SliceValue(vs ...Value) Value {
+	return Value{
+		num: uint64(len(vs)),
+		any: sliceptr(unsafe.SliceData(vs)),
+	}
+}
+
+// MapValue returns a new [Value] for a slice of key-value pairs. The passed
+// slice must not be changed after it is passed.
+func MapValue(kvs ...Attr) Value {
+	return Value{
+		num: uint64(len(kvs)),
+		any: mapptr(unsafe.SliceData(kvs)),
+	}
+}
+
+// AsString returns the value held by v as a string.
+func (v Value) AsString() string {
+	if sp, ok := v.any.(stringptr); ok {
+		return unsafe.String(sp, v.num)
+	}
+	// TODO: error handle
+	return ""
+}
+
+// asString returns the value held by v as a string. It will panic if the Value
+// is not KindString.
+func (v Value) asString() string {
+	return unsafe.String(v.any.(stringptr), v.num)
+}
+
+// AsInt64 returns the value held by v as an int64.
+func (v Value) AsInt64() int64 {
+	if v.Kind() != ValueKindInt64 {
+		// TODO: error handle
+		return 0
+	}
+	return v.asInt64()
+}
+
+// asInt64 returns the value held by v as an int64. If v is not of KindInt64,
+// this will return garbage.
+func (v Value) asInt64() int64 {
+	// Assumes v.num was a valid int64 (overflow not checked).
+	return int64(v.num) // nolint: gosec
+}
+
+// AsBool returns the value held by v as a bool.
+func (v Value) AsBool() bool {
+	if v.Kind() != ValueKindBool {
+		// TODO: error handle
+		return false
+	}
+	return v.asBool()
+}
+
+// asBool returns the value held by v as a bool. If v is not of KindBool, this
+// will return garbage.
+func (v Value) asBool() bool { return v.num == 1 }
+
+// AsFloat64 returns the value held by v as a float64.
+func (v Value) AsFloat64() float64 {
+	if v.Kind() != ValueKindFloat64 {
+		// TODO: error handle
+		return 0
+	}
+	return v.asFloat64()
+}
+
+// asFloat64 returns the value held by v as a float64. If v is not of
+// KindFloat64, this will return garbage.
+func (v Value) asFloat64() float64 { return math.Float64frombits(v.num) }
+
+// AsBytes returns the value held by v as a []byte.
+func (v Value) AsBytes() []byte {
+	if sp, ok := v.any.(bytesptr); ok {
+		return unsafe.Slice((*byte)(sp), v.num)
+	}
+	// TODO: error handle
+	return nil
+}
+
+// asBytes returns the value held by v as a []byte. It will panic if the Value
+// is not KindBytes.
+func (v Value) asBytes() []byte {
+	return unsafe.Slice((*byte)(v.any.(bytesptr)), v.num)
+}
+
+// AsSlice returns the value held by v as a []Value.
+func (v Value) AsSlice() []Value {
+	if sp, ok := v.any.(sliceptr); ok {
+		return unsafe.Slice((*Value)(sp), v.num)
+	}
+	// TODO: error handle
+	return nil
+}
+
+// asSlice returns the value held by v as a []Value. It will panic if the Value
+// is not KindSlice.
+func (v Value) asSlice() []Value {
+	return unsafe.Slice((*Value)(v.any.(sliceptr)), v.num)
+}
+
+// AsMap returns the value held by v as a []Attr.
+func (v Value) AsMap() []Attr {
+	if sp, ok := v.any.(mapptr); ok {
+		return unsafe.Slice((*Attr)(sp), v.num)
+	}
+	// TODO: error handle
+	return nil
+}
+
+// asMap returns the value held by v as a []Attr. It will panic if the
+// Value is not KindMap.
+func (v Value) asMap() []Attr {
+	return unsafe.Slice((*Attr)(v.any.(mapptr)), v.num)
+}
+
+// Kind returns the Kind of v.
+func (v Value) Kind() ValueKind {
+	switch x := v.any.(type) {
+	case ValueKind:
+		return x
+	case stringptr:
+		return ValueKindString
+	case bytesptr:
+		return ValueKindBytes
+	case sliceptr:
+		return ValueKindSlice
+	case mapptr:
+		return ValueKindMap
+	default:
+		return ValueKindEmpty
+	}
+}
+
+// Empty returns if v does not hold any value.
+func (v Value) Empty() bool { return v.Kind() == ValueKindEmpty }
+
+// Equal returns if v is equal to w.
+func (v Value) Equal(w Value) bool {
+	k1 := v.Kind()
+	k2 := w.Kind()
+	if k1 != k2 {
+		return false
+	}
+	switch k1 {
+	case ValueKindInt64, ValueKindBool:
+		return v.num == w.num
+	case ValueKindString:
+		return v.asString() == w.asString()
+	case ValueKindFloat64:
+		return v.asFloat64() == w.asFloat64()
+	case ValueKindSlice:
+		return slices.EqualFunc(v.asSlice(), w.asSlice(), Value.Equal)
+	case ValueKindMap:
+		sv := sortMap(v.asMap())
+		sw := sortMap(w.asMap())
+		return slices.EqualFunc(sv, sw, Attr.Equal)
+	case ValueKindBytes:
+		return bytes.Equal(v.asBytes(), w.asBytes())
+	case ValueKindEmpty:
+		return true
+	default:
+		// TODO: error handle
+		return false
+	}
+}
+
+func sortMap(m []Attr) []Attr {
+	sm := make([]Attr, len(m))
+	copy(sm, m)
+	slices.SortFunc(sm, func(a, b Attr) int {
+		return cmp.Compare(a.Key, b.Key)
+	})
+
+	return sm
+}
+
+// String returns Value's value as a string, formatted like [fmt.Sprint].
+//
+// The returned string is meant for debugging;
+// the string representation is not stable.
+func (v Value) String() string {
+	switch v.Kind() {
+	case ValueKindString:
+		return v.asString()
+	case ValueKindInt64:
+		// Assumes v.num was a valid int64 (overflow not checked).
+		return strconv.FormatInt(int64(v.num), 10) // nolint: gosec
+	case ValueKindFloat64:
+		return strconv.FormatFloat(v.asFloat64(), 'g', -1, 64)
+	case ValueKindBool:
+		return strconv.FormatBool(v.asBool())
+	case ValueKindBytes:
+		return fmt.Sprint(v.asBytes())
+	case ValueKindMap:
+		return fmt.Sprint(v.asMap())
+	case ValueKindSlice:
+		return fmt.Sprint(v.asSlice())
+	case ValueKindEmpty:
+		return "<nil>"
+	default:
+		// Try to handle this as gracefully as possible.
+		//
+		// Don't panic here. The goal here is to have developers find this
+		// first if a slog.Kind is is not handled. It is
+		// preferable to have user's open issue asking why their attributes
+		// have a "unhandled: " prefix than say that their code is panicking.
+		return fmt.Sprintf("<unhandled telemetry.ValueKind: %s>", v.Kind())
+	}
+}
+
+// MarshalJSON encodes v into OTLP formatted JSON.
+func (v *Value) MarshalJSON() ([]byte, error) {
+	switch v.Kind() {
+	case ValueKindString:
+		return json.Marshal(struct {
+			Value string `json:"stringValue"`
+		}{v.asString()})
+	case ValueKindInt64:
+		return json.Marshal(struct {
+			Value string `json:"intValue"`
+		}{strconv.FormatInt(int64(v.num), 10)})
+	case ValueKindFloat64:
+		return json.Marshal(struct {
+			Value float64 `json:"doubleValue"`
+		}{v.asFloat64()})
+	case ValueKindBool:
+		return json.Marshal(struct {
+			Value bool `json:"boolValue"`
+		}{v.asBool()})
+	case ValueKindBytes:
+		return json.Marshal(struct {
+			Value []byte `json:"bytesValue"`
+		}{v.asBytes()})
+	case ValueKindMap:
+		return json.Marshal(struct {
+			Value struct {
+				Values []Attr `json:"values"`
+			} `json:"kvlistValue"`
+		}{struct {
+			Values []Attr `json:"values"`
+		}{v.asMap()}})
+	case ValueKindSlice:
+		return json.Marshal(struct {
+			Value struct {
+				Values []Value `json:"values"`
+			} `json:"arrayValue"`
+		}{struct {
+			Values []Value `json:"values"`
+		}{v.asSlice()}})
+	case ValueKindEmpty:
+		return nil, nil
+	default:
+		return nil, fmt.Errorf("unknown Value kind: %s", v.Kind().String())
+	}
+}
+
+// UnmarshalJSON decodes the OTLP formatted JSON contained in data into v.
+func (v *Value) UnmarshalJSON(data []byte) error {
+	decoder := json.NewDecoder(bytes.NewReader(data))
+
+	t, err := decoder.Token()
+	if err != nil {
+		return err
+	}
+	if t != json.Delim('{') {
+		return errors.New("invalid Value type")
+	}
+
+	for decoder.More() {
+		keyIface, err := decoder.Token()
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				// Empty.
+				return nil
+			}
+			return err
+		}
+
+		key, ok := keyIface.(string)
+		if !ok {
+			return fmt.Errorf("invalid Value key: %#v", keyIface)
+		}
+
+		switch key {
+		case "stringValue", "string_value":
+			var val string
+			err = decoder.Decode(&val)
+			*v = StringValue(val)
+		case "boolValue", "bool_value":
+			var val bool
+			err = decoder.Decode(&val)
+			*v = BoolValue(val)
+		case "intValue", "int_value":
+			var val protoInt64
+			err = decoder.Decode(&val)
+			*v = Int64Value(val.Int64())
+		case "doubleValue", "double_value":
+			var val float64
+			err = decoder.Decode(&val)
+			*v = Float64Value(val)
+		case "bytesValue", "bytes_value":
+			var val64 string
+			if err := decoder.Decode(&val64); err != nil {
+				return err
+			}
+			var val []byte
+			val, err = base64.StdEncoding.DecodeString(val64)
+			*v = BytesValue(val)
+		case "arrayValue", "array_value":
+			var val struct{ Values []Value }
+			err = decoder.Decode(&val)
+			*v = SliceValue(val.Values...)
+		case "kvlistValue", "kvlist_value":
+			var val struct{ Values []Attr }
+			err = decoder.Decode(&val)
+			*v = MapValue(val.Values...)
+		default:
+			// Skip unknown.
+			continue
+		}
+		// Use first valid. Ignore the rest.
+		return err
+	}
+
+	// Only unknown fields. Return nil without unmarshaling any value.
+	return nil
+}

vendor/go.opentelemetry.io/auto/sdk/limit.go

@@ -0,0 +1,94 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package sdk
+
+import (
+	"log/slog"
+	"os"
+	"strconv"
+)
+
+// maxSpan are the span limits resolved during startup.
+var maxSpan = newSpanLimits()
+
+type spanLimits struct {
+	// Attrs is the number of allowed attributes for a span.
+	//
+	// This is resolved from the environment variable value for the
+	// OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT key if it exists. Otherwise, the
+	// environment variable value for OTEL_ATTRIBUTE_COUNT_LIMIT, or 128 if
+	// that is not set, is used.
+	Attrs int
+	// AttrValueLen is the maximum attribute value length allowed for a span.
+	//
+	// This is resolved from the environment variable value for the
+	// OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT key if it exists. Otherwise, the
+	// environment variable value for OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT, or -1
+	// if that is not set, is used.
+	AttrValueLen int
+	// Events is the number of allowed events for a span.
+	//
+	// This is resolved from the environment variable value for the
+	// OTEL_SPAN_EVENT_COUNT_LIMIT key, or 128 is used if that is not set.
+	Events int
+	// EventAttrs is the number of allowed attributes for a span event.
+	//
+	// The is resolved from the environment variable value for the
+	// OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT key, or 128 is used if that is not set.
+	EventAttrs int
+	// Links is the number of allowed Links for a span.
+	//
+	// This is resolved from the environment variable value for the
+	// OTEL_SPAN_LINK_COUNT_LIMIT, or 128 is used if that is not set.
+	Links int
+	// LinkAttrs is the number of allowed attributes for a span link.
+	//
+	// This is resolved from the environment variable value for the
+	// OTEL_LINK_ATTRIBUTE_COUNT_LIMIT, or 128 is used if that is not set.
+	LinkAttrs int
+}
+
+func newSpanLimits() spanLimits {
+	return spanLimits{
+		Attrs: firstEnv(
+			128,
+			"OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT",
+			"OTEL_ATTRIBUTE_COUNT_LIMIT",
+		),
+		AttrValueLen: firstEnv(
+			-1, // Unlimited.
+			"OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT",
+			"OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT",
+		),
+		Events:     firstEnv(128, "OTEL_SPAN_EVENT_COUNT_LIMIT"),
+		EventAttrs: firstEnv(128, "OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT"),
+		Links:      firstEnv(128, "OTEL_SPAN_LINK_COUNT_LIMIT"),
+		LinkAttrs:  firstEnv(128, "OTEL_LINK_ATTRIBUTE_COUNT_LIMIT"),
+	}
+}
+
+// firstEnv returns the parsed integer value of the first matching environment
+// variable from keys. The defaultVal is returned if the value is not an
+// integer or no match is found.
+func firstEnv(defaultVal int, keys ...string) int {
+	for _, key := range keys {
+		strV := os.Getenv(key)
+		if strV == "" {
+			continue
+		}
+
+		v, err := strconv.Atoi(strV)
+		if err == nil {
+			return v
+		}
+		slog.Warn(
+			"invalid limit environment variable",
+			"error", err,
+			"key", key,
+			"value", strV,
+		)
+	}
+
+	return defaultVal
+}

vendor/go.opentelemetry.io/auto/sdk/span.go

@@ -0,0 +1,432 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package sdk
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"runtime"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+	"unicode/utf8"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	semconv "go.opentelemetry.io/otel/semconv/v1.26.0"
+	"go.opentelemetry.io/otel/trace"
+	"go.opentelemetry.io/otel/trace/noop"
+
+	"go.opentelemetry.io/auto/sdk/internal/telemetry"
+)
+
+type span struct {
+	noop.Span
+
+	spanContext trace.SpanContext
+	sampled     atomic.Bool
+
+	mu     sync.Mutex
+	traces *telemetry.Traces
+	span   *telemetry.Span
+}
+
+func (s *span) SpanContext() trace.SpanContext {
+	if s == nil {
+		return trace.SpanContext{}
+	}
+	// s.spanContext is immutable, do not acquire lock s.mu.
+	return s.spanContext
+}
+
+func (s *span) IsRecording() bool {
+	if s == nil {
+		return false
+	}
+
+	return s.sampled.Load()
+}
+
+func (s *span) SetStatus(c codes.Code, msg string) {
+	if s == nil || !s.sampled.Load() {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if s.span.Status == nil {
+		s.span.Status = new(telemetry.Status)
+	}
+
+	s.span.Status.Message = msg
+
+	switch c {
+	case codes.Unset:
+		s.span.Status.Code = telemetry.StatusCodeUnset
+	case codes.Error:
+		s.span.Status.Code = telemetry.StatusCodeError
+	case codes.Ok:
+		s.span.Status.Code = telemetry.StatusCodeOK
+	}
+}
+
+func (s *span) SetAttributes(attrs ...attribute.KeyValue) {
+	if s == nil || !s.sampled.Load() {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	limit := maxSpan.Attrs
+	if limit == 0 {
+		// No attributes allowed.
+		s.span.DroppedAttrs += uint32(len(attrs))
+		return
+	}
+
+	m := make(map[string]int)
+	for i, a := range s.span.Attrs {
+		m[a.Key] = i
+	}
+
+	for _, a := range attrs {
+		val := convAttrValue(a.Value)
+		if val.Empty() {
+			s.span.DroppedAttrs++
+			continue
+		}
+
+		if idx, ok := m[string(a.Key)]; ok {
+			s.span.Attrs[idx] = telemetry.Attr{
+				Key:   string(a.Key),
+				Value: val,
+			}
+		} else if limit < 0 || len(s.span.Attrs) < limit {
+			s.span.Attrs = append(s.span.Attrs, telemetry.Attr{
+				Key:   string(a.Key),
+				Value: val,
+			})
+			m[string(a.Key)] = len(s.span.Attrs) - 1
+		} else {
+			s.span.DroppedAttrs++
+		}
+	}
+}
+
+// convCappedAttrs converts up to limit attrs into a []telemetry.Attr. The
+// number of dropped attributes is also returned.
+func convCappedAttrs(limit int, attrs []attribute.KeyValue) ([]telemetry.Attr, uint32) {
+	if limit == 0 {
+		return nil, uint32(len(attrs))
+	}
+
+	if limit < 0 {
+		// Unlimited.
+		return convAttrs(attrs), 0
+	}
+
+	limit = min(len(attrs), limit)
+	return convAttrs(attrs[:limit]), uint32(len(attrs) - limit)
+}
+
+func convAttrs(attrs []attribute.KeyValue) []telemetry.Attr {
+	if len(attrs) == 0 {
+		// Avoid allocations if not necessary.
+		return nil
+	}
+
+	out := make([]telemetry.Attr, 0, len(attrs))
+	for _, attr := range attrs {
+		key := string(attr.Key)
+		val := convAttrValue(attr.Value)
+		if val.Empty() {
+			continue
+		}
+		out = append(out, telemetry.Attr{Key: key, Value: val})
+	}
+	return out
+}
+
+func convAttrValue(value attribute.Value) telemetry.Value {
+	switch value.Type() {
+	case attribute.BOOL:
+		return telemetry.BoolValue(value.AsBool())
+	case attribute.INT64:
+		return telemetry.Int64Value(value.AsInt64())
+	case attribute.FLOAT64:
+		return telemetry.Float64Value(value.AsFloat64())
+	case attribute.STRING:
+		v := truncate(maxSpan.AttrValueLen, value.AsString())
+		return telemetry.StringValue(v)
+	case attribute.BOOLSLICE:
+		slice := value.AsBoolSlice()
+		out := make([]telemetry.Value, 0, len(slice))
+		for _, v := range slice {
+			out = append(out, telemetry.BoolValue(v))
+		}
+		return telemetry.SliceValue(out...)
+	case attribute.INT64SLICE:
+		slice := value.AsInt64Slice()
+		out := make([]telemetry.Value, 0, len(slice))
+		for _, v := range slice {
+			out = append(out, telemetry.Int64Value(v))
+		}
+		return telemetry.SliceValue(out...)
+	case attribute.FLOAT64SLICE:
+		slice := value.AsFloat64Slice()
+		out := make([]telemetry.Value, 0, len(slice))
+		for _, v := range slice {
+			out = append(out, telemetry.Float64Value(v))
+		}
+		return telemetry.SliceValue(out...)
+	case attribute.STRINGSLICE:
+		slice := value.AsStringSlice()
+		out := make([]telemetry.Value, 0, len(slice))
+		for _, v := range slice {
+			v = truncate(maxSpan.AttrValueLen, v)
+			out = append(out, telemetry.StringValue(v))
+		}
+		return telemetry.SliceValue(out...)
+	}
+	return telemetry.Value{}
+}
+
+// truncate returns a truncated version of s such that it contains less than
+// the limit number of characters. Truncation is applied by returning the limit
+// number of valid characters contained in s.
+//
+// If limit is negative, it returns the original string.
+//
+// UTF-8 is supported. When truncating, all invalid characters are dropped
+// before applying truncation.
+//
+// If s already contains less than the limit number of bytes, it is returned
+// unchanged. No invalid characters are removed.
+func truncate(limit int, s string) string {
+	// This prioritize performance in the following order based on the most
+	// common expected use-cases.
+	//
+	//  - Short values less than the default limit (128).
+	//  - Strings with valid encodings that exceed the limit.
+	//  - No limit.
+	//  - Strings with invalid encodings that exceed the limit.
+	if limit < 0 || len(s) <= limit {
+		return s
+	}
+
+	// Optimistically, assume all valid UTF-8.
+	var b strings.Builder
+	count := 0
+	for i, c := range s {
+		if c != utf8.RuneError {
+			count++
+			if count > limit {
+				return s[:i]
+			}
+			continue
+		}
+
+		_, size := utf8.DecodeRuneInString(s[i:])
+		if size == 1 {
+			// Invalid encoding.
+			b.Grow(len(s) - 1)
+			_, _ = b.WriteString(s[:i])
+			s = s[i:]
+			break
+		}
+	}
+
+	// Fast-path, no invalid input.
+	if b.Cap() == 0 {
+		return s
+	}
+
+	// Truncate while validating UTF-8.
+	for i := 0; i < len(s) && count < limit; {
+		c := s[i]
+		if c < utf8.RuneSelf {
+			// Optimization for single byte runes (common case).
+			_ = b.WriteByte(c)
+			i++
+			count++
+			continue
+		}
+
+		_, size := utf8.DecodeRuneInString(s[i:])
+		if size == 1 {
+			// We checked for all 1-byte runes above, this is a RuneError.
+			i++
+			continue
+		}
+
+		_, _ = b.WriteString(s[i : i+size])
+		i += size
+		count++
+	}
+
+	return b.String()
+}
+
+func (s *span) End(opts ...trace.SpanEndOption) {
+	if s == nil || !s.sampled.Swap(false) {
+		return
+	}
+
+	// s.end exists so the lock (s.mu) is not held while s.ended is called.
+	s.ended(s.end(opts))
+}
+
+func (s *span) end(opts []trace.SpanEndOption) []byte {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	cfg := trace.NewSpanEndConfig(opts...)
+	if t := cfg.Timestamp(); !t.IsZero() {
+		s.span.EndTime = cfg.Timestamp()
+	} else {
+		s.span.EndTime = time.Now()
+	}
+
+	b, _ := json.Marshal(s.traces) // TODO: do not ignore this error.
+	return b
+}
+
+// Expected to be implemented in eBPF.
+//
+//go:noinline
+func (*span) ended(buf []byte) { ended(buf) }
+
+// ended is used for testing.
+var ended = func([]byte) {}
+
+func (s *span) RecordError(err error, opts ...trace.EventOption) {
+	if s == nil || err == nil || !s.sampled.Load() {
+		return
+	}
+
+	cfg := trace.NewEventConfig(opts...)
+
+	attrs := cfg.Attributes()
+	attrs = append(attrs,
+		semconv.ExceptionType(typeStr(err)),
+		semconv.ExceptionMessage(err.Error()),
+	)
+	if cfg.StackTrace() {
+		buf := make([]byte, 2048)
+		n := runtime.Stack(buf, false)
+		attrs = append(attrs, semconv.ExceptionStacktrace(string(buf[0:n])))
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.addEvent(semconv.ExceptionEventName, cfg.Timestamp(), attrs)
+}
+
+func typeStr(i any) string {
+	t := reflect.TypeOf(i)
+	if t.PkgPath() == "" && t.Name() == "" {
+		// Likely a builtin type.
+		return t.String()
+	}
+	return fmt.Sprintf("%s.%s", t.PkgPath(), t.Name())
+}
+
+func (s *span) AddEvent(name string, opts ...trace.EventOption) {
+	if s == nil || !s.sampled.Load() {
+		return
+	}
+
+	cfg := trace.NewEventConfig(opts...)
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.addEvent(name, cfg.Timestamp(), cfg.Attributes())
+}
+
+// addEvent adds an event with name and attrs at tStamp to the span. The span
+// lock (s.mu) needs to be held by the caller.
+func (s *span) addEvent(name string, tStamp time.Time, attrs []attribute.KeyValue) {
+	limit := maxSpan.Events
+
+	if limit == 0 {
+		s.span.DroppedEvents++
+		return
+	}
+
+	if limit > 0 && len(s.span.Events) == limit {
+		// Drop head while avoiding allocation of more capacity.
+		copy(s.span.Events[:limit-1], s.span.Events[1:])
+		s.span.Events = s.span.Events[:limit-1]
+		s.span.DroppedEvents++
+	}
+
+	e := &telemetry.SpanEvent{Time: tStamp, Name: name}
+	e.Attrs, e.DroppedAttrs = convCappedAttrs(maxSpan.EventAttrs, attrs)
+
+	s.span.Events = append(s.span.Events, e)
+}
+
+func (s *span) AddLink(link trace.Link) {
+	if s == nil || !s.sampled.Load() {
+		return
+	}
+
+	l := maxSpan.Links
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if l == 0 {
+		s.span.DroppedLinks++
+		return
+	}
+
+	if l > 0 && len(s.span.Links) == l {
+		// Drop head while avoiding allocation of more capacity.
+		copy(s.span.Links[:l-1], s.span.Links[1:])
+		s.span.Links = s.span.Links[:l-1]
+		s.span.DroppedLinks++
+	}
+
+	s.span.Links = append(s.span.Links, convLink(link))
+}
+
+func convLinks(links []trace.Link) []*telemetry.SpanLink {
+	out := make([]*telemetry.SpanLink, 0, len(links))
+	for _, link := range links {
+		out = append(out, convLink(link))
+	}
+	return out
+}
+
+func convLink(link trace.Link) *telemetry.SpanLink {
+	l := &telemetry.SpanLink{
+		TraceID:    telemetry.TraceID(link.SpanContext.TraceID()),
+		SpanID:     telemetry.SpanID(link.SpanContext.SpanID()),
+		TraceState: link.SpanContext.TraceState().String(),
+		Flags:      uint32(link.SpanContext.TraceFlags()),
+	}
+	l.Attrs, l.DroppedAttrs = convCappedAttrs(maxSpan.LinkAttrs, link.Attributes)
+
+	return l
+}
+
+func (s *span) SetName(name string) {
+	if s == nil || !s.sampled.Load() {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.span.Name = name
+}
+
+func (*span) TracerProvider() trace.TracerProvider { return TracerProvider() }

vendor/go.opentelemetry.io/auto/sdk/tracer.go

@@ -0,0 +1,124 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package sdk
+
+import (
+	"context"
+	"time"
+
+	"go.opentelemetry.io/otel/trace"
+	"go.opentelemetry.io/otel/trace/noop"
+
+	"go.opentelemetry.io/auto/sdk/internal/telemetry"
+)
+
+type tracer struct {
+	noop.Tracer
+
+	name, schemaURL, version string
+}
+
+var _ trace.Tracer = tracer{}
+
+func (t tracer) Start(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	var psc trace.SpanContext
+	sampled := true
+	span := new(span)
+
+	// Ask eBPF for sampling decision and span context info.
+	t.start(ctx, span, &psc, &sampled, &span.spanContext)
+
+	span.sampled.Store(sampled)
+
+	ctx = trace.ContextWithSpan(ctx, span)
+
+	if sampled {
+		// Only build traces if sampled.
+		cfg := trace.NewSpanStartConfig(opts...)
+		span.traces, span.span = t.traces(name, cfg, span.spanContext, psc)
+	}
+
+	return ctx, span
+}
+
+// Expected to be implemented in eBPF.
+//
+//go:noinline
+func (t *tracer) start(
+	ctx context.Context,
+	spanPtr *span,
+	psc *trace.SpanContext,
+	sampled *bool,
+	sc *trace.SpanContext,
+) {
+	start(ctx, spanPtr, psc, sampled, sc)
+}
+
+// start is used for testing.
+var start = func(context.Context, *span, *trace.SpanContext, *bool, *trace.SpanContext) {}
+
+func (t tracer) traces(name string, cfg trace.SpanConfig, sc, psc trace.SpanContext) (*telemetry.Traces, *telemetry.Span) {
+	span := &telemetry.Span{
+		TraceID:      telemetry.TraceID(sc.TraceID()),
+		SpanID:       telemetry.SpanID(sc.SpanID()),
+		Flags:        uint32(sc.TraceFlags()),
+		TraceState:   sc.TraceState().String(),
+		ParentSpanID: telemetry.SpanID(psc.SpanID()),
+		Name:         name,
+		Kind:         spanKind(cfg.SpanKind()),
+	}
+
+	span.Attrs, span.DroppedAttrs = convCappedAttrs(maxSpan.Attrs, cfg.Attributes())
+
+	links := cfg.Links()
+	if limit := maxSpan.Links; limit == 0 {
+		span.DroppedLinks = uint32(len(links))
+	} else {
+		if limit > 0 {
+			n := max(len(links)-limit, 0)
+			span.DroppedLinks = uint32(n)
+			links = links[n:]
+		}
+		span.Links = convLinks(links)
+	}
+
+	if t := cfg.Timestamp(); !t.IsZero() {
+		span.StartTime = cfg.Timestamp()
+	} else {
+		span.StartTime = time.Now()
+	}
+
+	return &telemetry.Traces{
+		ResourceSpans: []*telemetry.ResourceSpans{
+			{
+				ScopeSpans: []*telemetry.ScopeSpans{
+					{
+						Scope: &telemetry.Scope{
+							Name:    t.name,
+							Version: t.version,
+						},
+						Spans:     []*telemetry.Span{span},
+						SchemaURL: t.schemaURL,
+					},
+				},
+			},
+		},
+	}, span
+}
+
+func spanKind(kind trace.SpanKind) telemetry.SpanKind {
+	switch kind {
+	case trace.SpanKindInternal:
+		return telemetry.SpanKindInternal
+	case trace.SpanKindServer:
+		return telemetry.SpanKindServer
+	case trace.SpanKindClient:
+		return telemetry.SpanKindClient
+	case trace.SpanKindProducer:
+		return telemetry.SpanKindProducer
+	case trace.SpanKindConsumer:
+		return telemetry.SpanKindConsumer
+	}
+	return telemetry.SpanKind(0) // undefined.
+}

vendor/go.opentelemetry.io/auto/sdk/tracer_provider.go

@@ -0,0 +1,33 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package sdk
+
+import (
+	"go.opentelemetry.io/otel/trace"
+	"go.opentelemetry.io/otel/trace/noop"
+)
+
+// TracerProvider returns an auto-instrumentable [trace.TracerProvider].
+//
+// If an [go.opentelemetry.io/auto.Instrumentation] is configured to instrument
+// the process using the returned TracerProvider, all of the telemetry it
+// produces will be processed and handled by that Instrumentation. By default,
+// if no Instrumentation instruments the TracerProvider it will not generate
+// any trace telemetry.
+func TracerProvider() trace.TracerProvider { return tracerProviderInstance }
+
+var tracerProviderInstance = new(tracerProvider)
+
+type tracerProvider struct{ noop.TracerProvider }
+
+var _ trace.TracerProvider = tracerProvider{}
+
+func (p tracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.Tracer {
+	cfg := trace.NewTracerConfig(opts...)
+	return tracer{
+		name:      name,
+		version:   cfg.InstrumentationVersion(),
+		schemaURL: cfg.SchemaURL(),
+	}
+}

vendor/go.opentelemetry.io/otel/.gitignore

@@ -12,11 +12,3 @@ go.work
 go.work.sum
 
 gen/
-
-/example/dice/dice
-/example/namedtracer/namedtracer
-/example/otel-collector/otel-collector
-/example/opencensus/opencensus
-/example/passthrough/passthrough
-/example/prometheus/prometheus
-/example/zipkin/zipkin

vendor/go.opentelemetry.io/otel/.golangci.yml

@@ -22,13 +22,16 @@ linters:
     - govet
     - ineffassign
     - misspell
+    - perfsprint
     - revive
     - staticcheck
     - tenv
+    - testifylint
     - typecheck
     - unconvert
     - unused
     - unparam
+    - usestdlibvars
 
 issues:
   # Maximum issues count per one linter.
@@ -60,16 +63,17 @@ issues:
       text: "calls to (.+) only in main[(][)] or init[(][)] functions"
       linters:
         - revive
-    # It's okay to not run gosec in a test.
+    # It's okay to not run gosec and perfsprint in a test.
     - path: _test\.go
       linters:
         - gosec
-    # Igonoring gosec G404: Use of weak random number generator (math/rand instead of crypto/rand)
+        - perfsprint
+    # Ignoring gosec G404: Use of weak random number generator (math/rand instead of crypto/rand)
     # as we commonly use it in tests and examples.
     - text: "G404:"
       linters:
         - gosec
-    # Igonoring gosec G402: TLS MinVersion too low
+    # Ignoring gosec G402: TLS MinVersion too low
     # as the https://pkg.go.dev/crypto/tls#Config handles MinVersion default well.
     - text: "G402: TLS MinVersion too low."
       linters:
@@ -94,6 +98,13 @@ linters-settings:
           - pkg: "crypto/md5"
           - pkg: "crypto/sha1"
           - pkg: "crypto/**/pkix"
+      auto/sdk:
+        files:
+          - "!internal/global/trace.go"
+          - "~internal/global/trace_test.go"
+        deny:
+          - pkg: "go.opentelemetry.io/auto/sdk"
+            desc: Do not use SDK from automatic instrumentation.
       otlp-internal:
         files:
           - "!**/exporters/otlp/internal/**/*.go"
@@ -126,8 +137,6 @@ linters-settings:
           - "**/metric/**/*.go"
           - "**/bridge/*.go"
           - "**/bridge/**/*.go"
-          - "**/example/*.go"
-          - "**/example/**/*.go"
           - "**/trace/*.go"
           - "**/trace/**/*.go"
           - "**/log/*.go"
@@ -155,6 +164,12 @@ linters-settings:
     locale: US
     ignore-words:
       - cancelled
+  perfsprint:
+    err-error: true
+    errorf: true
+    int-conversion: true
+    sprintf1: true
+    strconcat: true
   revive:
     # Sets the default failure confidence.
     # This means that linting errors with less than 0.8 confidence will be ignored.
@@ -302,3 +317,9 @@ linters-settings:
       # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#waitgroup-by-value
       - name: waitgroup-by-value
         disabled: false
+  testifylint:
+    enable-all: true
+    disable:
+      - float-compare
+      - go-require
+      - require-error

vendor/go.opentelemetry.io/otel/CHANGELOG.md

@@ -11,6 +11,141 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 <!-- Released section -->
 <!-- Don't change this section unless doing release -->
 
+## [1.34.0/0.56.0/0.10.0] 2025-01-17
+
+### Changed
+
+- Remove the notices from `Logger` to make the whole Logs API user-facing in `go.opentelemetry.io/otel/log`. (#6167)
+
+### Fixed
+
+- Relax minimum Go version to 1.22.0 in various modules. (#6073)
+- The `Type` name logged for the `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc` client is corrected from `otlphttpgrpc` to `otlptracegrpc`. (#6143)
+- The `Type` name logged for the `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlphttpgrpc` client is corrected from `otlphttphttp` to `otlptracehttp`. (#6143)
+
+## [1.33.0/0.55.0/0.9.0/0.0.12] 2024-12-12
+
+### Added
+
+- Add `Reset` method to `SpanRecorder` in `go.opentelemetry.io/otel/sdk/trace/tracetest`. (#5994)
+- Add `EnabledInstrument` interface in `go.opentelemetry.io/otel/sdk/metric/internal/x`.
+  This is an experimental interface that is implemented by synchronous instruments provided by `go.opentelemetry.io/otel/sdk/metric`.
+  Users can use it to avoid performing computationally expensive operations when recording measurements.
+  It does not fall within the scope of the OpenTelemetry Go versioning and stability [policy](./VERSIONING.md) and it may be changed in backwards incompatible ways or removed in feature releases. (#6016)
+
+### Changed
+
+- The default global API now supports full auto-instrumentation from the `go.opentelemetry.io/auto` package.
+  See that package for more information. (#5920)
+- Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp`. (#5929)
+- Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp`. (#5929)
+- Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp`. (#5929)
+- Performance improvements for attribute value `AsStringSlice`, `AsFloat64Slice`, `AsInt64Slice`, `AsBoolSlice`. (#6011)
+- Change `EnabledParameters` to have a `Severity` field instead of a getter and setter in `go.opentelemetry.io/otel/log`. (#6009)
+
+### Fixed
+
+- Fix inconsistent request body closing in `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp`. (#5954)
+- Fix inconsistent request body closing in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp`. (#5954)
+- Fix inconsistent request body closing in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp`. (#5954)
+- Fix invalid exemplar keys in `go.opentelemetry.io/otel/exporters/prometheus`. (#5995)
+- Fix attribute value truncation in `go.opentelemetry.io/otel/sdk/trace`. (#5997)
+- Fix attribute value truncation in `go.opentelemetry.io/otel/sdk/log`. (#6032)
+
+## [1.32.0/0.54.0/0.8.0/0.0.11] 2024-11-08
+
+### Added
+
+- Add `go.opentelemetry.io/otel/sdk/metric/exemplar.AlwaysOffFilter`, which can be used to disable exemplar recording. (#5850)
+- Add `go.opentelemetry.io/otel/sdk/metric.WithExemplarFilter`, which can be used to configure the exemplar filter used by the metrics SDK. (#5850)
+- Add `ExemplarReservoirProviderSelector` and `DefaultExemplarReservoirProviderSelector` to `go.opentelemetry.io/otel/sdk/metric`, which defines the exemplar reservoir to use based on the aggregation of the metric. (#5861)
+- Add `ExemplarReservoirProviderSelector` to `go.opentelemetry.io/otel/sdk/metric.Stream` to allow using views to configure the exemplar reservoir to use for a metric. (#5861)
+- Add `ReservoirProvider`, `HistogramReservoirProvider` and `FixedSizeReservoirProvider` to `go.opentelemetry.io/otel/sdk/metric/exemplar` to make it convenient to use providers of Reservoirs. (#5861)
+- The `go.opentelemetry.io/otel/semconv/v1.27.0` package.
+  The package contains semantic conventions from the `v1.27.0` version of the OpenTelemetry Semantic Conventions. (#5894)
+- Add `Attributes attribute.Set` field to `Scope` in `go.opentelemetry.io/otel/sdk/instrumentation`. (#5903)
+- Add `Attributes attribute.Set` field to `ScopeRecords` in `go.opentelemetry.io/otel/log/logtest`. (#5927)
+- `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc` adds instrumentation scope attributes. (#5934)
+- `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp` adds instrumentation scope attributes. (#5934)
+- `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc` adds instrumentation scope attributes. (#5935)
+- `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp` adds instrumentation scope attributes. (#5935)
+- `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc` adds instrumentation scope attributes. (#5933)
+- `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp` adds instrumentation scope attributes. (#5933)
+- `go.opentelemetry.io/otel/exporters/prometheus` adds instrumentation scope attributes in `otel_scope_info` metric as labels. (#5932)
+
+### Changed
+
+- Support scope attributes and make them as identifying for `Tracer` in `go.opentelemetry.io/otel` and `go.opentelemetry.io/otel/sdk/trace`. (#5924)
+- Support scope attributes and make them as identifying for `Meter` in `go.opentelemetry.io/otel` and `go.opentelemetry.io/otel/sdk/metric`. (#5926)
+- Support scope attributes and make them as identifying for `Logger` in `go.opentelemetry.io/otel` and `go.opentelemetry.io/otel/sdk/log`. (#5925)
+- Make schema URL and scope attributes as identifying for `Tracer` in `go.opentelemetry.io/otel/bridge/opentracing`. (#5931)
+- Clear unneeded slice elements to allow GC to collect the objects in `go.opentelemetry.io/otel/sdk/metric` and `go.opentelemetry.io/otel/sdk/trace`. (#5804)
+
+### Fixed
+
+- Global MeterProvider registration unwraps global instrument Observers, the undocumented Unwrap() methods are now private. (#5881)
+- `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc` now keeps the metadata already present in the context when `WithHeaders` is used. (#5892)
+- `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc` now keeps the metadata already present in the context when `WithHeaders` is used. (#5911)
+- `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc` now keeps the metadata already present in the context when `WithHeaders` is used. (#5915)
+- Fix `go.opentelemetry.io/otel/exporters/prometheus` trying to add exemplars to Gauge metrics, which is unsupported. (#5912)
+- Fix `WithEndpointURL` to always use a secure connection when an https URL is passed in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc`. (#5944)
+- Fix `WithEndpointURL` to always use a secure connection when an https URL is passed in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp`. (#5944)
+- Fix `WithEndpointURL` to always use a secure connection when an https URL is passed in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc`. (#5944)
+- Fix `WithEndpointURL` to always use a secure connection when an https URL is passed in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp`. (#5944)
+- Fix incorrect metrics generated from callbacks when multiple readers are used in `go.opentelemetry.io/otel/sdk/metric`. (#5900)
+
+### Removed
+
+- Remove all examples under `go.opentelemetry.io/otel/example` as they are moved to [Contrib repository](https://github.com/open-telemetry/opentelemetry-go-contrib/tree/main/examples). (#5930)
+
+## [1.31.0/0.53.0/0.7.0/0.0.10] 2024-10-11
+
+### Added
+
+- Add `go.opentelemetry.io/otel/sdk/metric/exemplar` package which includes `Exemplar`, `Filter`, `TraceBasedFilter`, `AlwaysOnFilter`, `HistogramReservoir`, `FixedSizeReservoir`, `Reservoir`, `Value` and `ValueType` types. These will be used for configuring the exemplar reservoir for the metrics sdk. (#5747, #5862)
+- Add `WithExportBufferSize` option to log batch processor.(#5877)
+
+### Changed
+
+- Enable exemplars by default in `go.opentelemetry.io/otel/sdk/metric`. Exemplars can be disabled by setting `OTEL_METRICS_EXEMPLAR_FILTER=always_off` (#5778)
+- `Logger.Enabled` in `go.opentelemetry.io/otel/log` now accepts a newly introduced `EnabledParameters` type instead of `Record`. (#5791)
+- `FilterProcessor.Enabled` in `go.opentelemetry.io/otel/sdk/log/internal/x` now accepts `EnabledParameters` instead of `Record`. (#5791)
+- The `Record` type in `go.opentelemetry.io/otel/log` is no longer comparable. (#5847)
+- Performance improvements for the trace SDK `SetAttributes` method in `Span`. (#5864)
+- Reduce memory allocations for the `Event` and `Link` lists in `Span`. (#5858)
+- Performance improvements for the trace SDK `AddEvent`, `AddLink`, `RecordError` and `End` methods in `Span`. (#5874)
+
+### Deprecated
+
+- Deprecate all examples under `go.opentelemetry.io/otel/example` as they are moved to [Contrib repository](https://github.com/open-telemetry/opentelemetry-go-contrib/tree/main/examples). (#5854)
+
+### Fixed
+
+- The race condition for multiple `FixedSize` exemplar reservoirs identified in #5814 is resolved. (#5819)
+- Fix log records duplication in case of heterogeneous resource attributes by correctly mapping each log record to it's resource and scope. (#5803)
+- Fix timer channel drain to avoid hanging on Go 1.23. (#5868)
+- Fix delegation for global meter providers, and panic when calling otel.SetMeterProvider. (#5827)
+- Change the `reflect.TypeOf` to use a nil pointer to not allocate on the heap unless necessary. (#5827)
+
+## [1.30.0/0.52.0/0.6.0/0.0.9] 2024-09-09
+
+### Added
+
+- Support `OTEL_EXPORTER_OTLP_LOGS_INSECURE` and `OTEL_EXPORTER_OTLP_INSECURE` environments in `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc`. (#5739)
+- The `WithResource` option for `NewMeterProvider` now merges the provided resources with the ones from environment variables. (#5773)
+- The `WithResource` option for `NewLoggerProvider` now merges the provided resources with the ones from environment variables. (#5773)
+- Add UTF-8 support to `go.opentelemetry.io/otel/exporters/prometheus`. (#5755)
+
+### Fixed
+
+- Fix memory leak in the global `MeterProvider` when identical instruments are repeatedly created. (#5754)
+- Fix panic on instruments creation when setting meter provider. (#5758)
+- Fix an issue where `SetMeterProvider` in `go.opentelemetry.io/otel` might miss the delegation for instruments and registries. (#5780)
+
+### Removed
+
+- Drop support for [Go 1.21]. (#5736, #5740, #5800)
+
 ## [1.29.0/0.51.0/0.5.0] 2024-08-23
 
 This release is the last to support [Go 1.21].
@@ -1895,7 +2030,7 @@ with major version 0.
 - Setting error status while recording error with Span from oteltest package. (#1729)
 - The concept of a remote and local Span stored in a context is unified to just the current Span.
   Because of this `"go.opentelemetry.io/otel/trace".RemoteSpanContextFromContext` is removed as it is no longer needed.
-  Instead, `"go.opentelemetry.io/otel/trace".SpanContextFromContex` can be used to return the current Span.
+  Instead, `"go.opentelemetry.io/otel/trace".SpanContextFromContext` can be used to return the current Span.
   If needed, that Span's `SpanContext.IsRemote()` can then be used to determine if it is remote or not. (#1731)
 - The `HasRemoteParent` field of the `"go.opentelemetry.io/otel/sdk/trace".SamplingParameters` is removed.
   This field is redundant to the information returned from the `Remote` method of the `SpanContext` held in the `ParentContext` field. (#1749)
@@ -2469,7 +2604,7 @@ This release migrates the default OpenTelemetry SDK into its own Go module, deco
 - Prometheus exporter will not apply stale updates or forget inactive metrics. (#903)
 - Add test for api.standard `HTTPClientAttributesFromHTTPRequest`. (#905)
 - Bump github.com/golangci/golangci-lint from 1.27.0 to 1.28.1 in /tools. (#901, #913)
-- Update otel-colector example to use the v0.5.0 collector. (#915)
+- Update otel-collector example to use the v0.5.0 collector. (#915)
 - The `grpctrace` instrumentation uses a span name conforming to the OpenTelemetry semantic conventions (does not contain a leading slash (`/`)). (#922)
 - The `grpctrace` instrumentation includes an `rpc.method` attribute now set to the gRPC method name. (#900, #922)
 - The `grpctrace` instrumentation `rpc.service` attribute now contains the package name if one exists.
@@ -3062,7 +3197,12 @@ It contains api and sdk for trace and meter.
 - CircleCI build CI manifest files.
 - CODEOWNERS file to track owners of this project.
 
-[Unreleased]: https://github.com/open-telemetry/opentelemetry-go/compare/v1.29.0...HEAD
+[Unreleased]: https://github.com/open-telemetry/opentelemetry-go/compare/v1.34.0...HEAD
+[1.34.0/0.56.0/0.10.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.34.0
+[1.33.0/0.55.0/0.9.0/0.0.12]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.33.0
+[1.32.0/0.54.0/0.8.0/0.0.11]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.32.0
+[1.31.0/0.53.0/0.7.0/0.0.10]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.31.0
+[1.30.0/0.52.0/0.6.0/0.0.9]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.30.0
 [1.29.0/0.51.0/0.5.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.29.0
 [1.28.0/0.50.0/0.4.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.28.0
 [1.27.0/0.49.0/0.3.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.27.0

vendor/go.opentelemetry.io/otel/CODEOWNERS

@@ -12,6 +12,6 @@
 #  https://help.github.com/en/articles/about-code-owners
 #
 
-* @MrAlias @XSAM @dashpole @MadVikingGod @pellared @hanyuancheung @dmathieu
+* @MrAlias @XSAM @dashpole @pellared @dmathieu
 
-CODEOWNERS @MrAlias @MadVikingGod @pellared @dashpole @XSAM @dmathieu
+CODEOWNERS @MrAlias @pellared @dashpole @XSAM @dmathieu

vendor/go.opentelemetry.io/otel/CONTRIBUTING.md

@@ -578,7 +578,10 @@ See also:
 The tests should never leak goroutines.
 
 Use the term `ConcurrentSafe` in the test name when it aims to verify the
-absence of race conditions.
+absence of race conditions. The top-level tests with this term will be run
+many times in the `test-concurrent-safe` CI job to increase the chance of
+catching concurrency issues. This does not apply to subtests when this term
+is not in their root name.
 
 ### Internal packages
 
@@ -626,13 +629,14 @@ should be canceled.
 
 ## Approvers and Maintainers
 
-### Approvers
+### Triagers
 
-- [Chester Cheung](https://github.com/hanyuancheung), Tencent
+- [Cheng-Zhen Yang](https://github.com/scorpionknifes), Independent
+
+### Approvers
 
 ### Maintainers
 
-- [Aaron Clawson](https://github.com/MadVikingGod), LightStep
 - [Damien Mathieu](https://github.com/dmathieu), Elastic
 - [David Ashpole](https://github.com/dashpole), Google
 - [Robert Pająk](https://github.com/pellared), Splunk
@@ -641,11 +645,13 @@ should be canceled.
 
 ### Emeritus
 
-- [Liz Fong-Jones](https://github.com/lizthegrey), Honeycomb
-- [Gustavo Silva Paiva](https://github.com/paivagustavo), LightStep
-- [Josh MacDonald](https://github.com/jmacd), LightStep
-- [Anthony Mirabella](https://github.com/Aneurysm9), AWS
-- [Evan Torrie](https://github.com/evantorrie), Yahoo
+- [Aaron Clawson](https://github.com/MadVikingGod)
+- [Anthony Mirabella](https://github.com/Aneurysm9)
+- [Chester Cheung](https://github.com/hanyuancheung)
+- [Evan Torrie](https://github.com/evantorrie)
+- [Gustavo Silva Paiva](https://github.com/paivagustavo)
+- [Josh MacDonald](https://github.com/jmacd)
+- [Liz Fong-Jones](https://github.com/lizthegrey)
 
 ### Become an Approver or a Maintainer
 

vendor/go.opentelemetry.io/otel/Makefile

@@ -14,8 +14,8 @@ TIMEOUT = 60
 .DEFAULT_GOAL := precommit
 
 .PHONY: precommit ci
-precommit: generate license-check misspell go-mod-tidy golangci-lint-fix verify-readmes verify-mods test-default
-ci: generate license-check lint vanity-import-check verify-readmes verify-mods build test-default check-clean-work-tree test-coverage
+precommit: generate toolchain-check license-check misspell go-mod-tidy golangci-lint-fix verify-readmes verify-mods test-default
+ci: generate toolchain-check license-check lint vanity-import-check verify-readmes verify-mods build test-default check-clean-work-tree test-coverage
 
 # Tools
 
@@ -54,9 +54,6 @@ $(TOOLS)/stringer: PACKAGE=golang.org/x/tools/cmd/stringer
 PORTO = $(TOOLS)/porto
 $(TOOLS)/porto: PACKAGE=github.com/jcchavezs/porto/cmd/porto
 
-GOJQ = $(TOOLS)/gojq
-$(TOOLS)/gojq: PACKAGE=github.com/itchyny/gojq/cmd/gojq
-
 GOTMPL = $(TOOLS)/gotmpl
 $(GOTMPL): PACKAGE=go.opentelemetry.io/build-tools/gotmpl
 
@@ -67,7 +64,7 @@ GOVULNCHECK = $(TOOLS)/govulncheck
 $(TOOLS)/govulncheck: PACKAGE=golang.org/x/vuln/cmd/govulncheck
 
 .PHONY: tools
-tools: $(CROSSLINK) $(GOLANGCI_LINT) $(MISSPELL) $(GOCOVMERGE) $(STRINGER) $(PORTO) $(GOJQ) $(SEMCONVGEN) $(MULTIMOD) $(SEMCONVKIT) $(GOTMPL) $(GORELEASE)
+tools: $(CROSSLINK) $(GOLANGCI_LINT) $(MISSPELL) $(GOCOVMERGE) $(STRINGER) $(PORTO) $(SEMCONVGEN) $(MULTIMOD) $(SEMCONVKIT) $(GOTMPL) $(GORELEASE)
 
 # Virtualized python tools via docker
 
@@ -145,12 +142,14 @@ build-tests/%:
 
 # Tests
 
-TEST_TARGETS := test-default test-bench test-short test-verbose test-race
+TEST_TARGETS := test-default test-bench test-short test-verbose test-race test-concurrent-safe
 .PHONY: $(TEST_TARGETS) test
 test-default test-race: ARGS=-race
 test-bench:   ARGS=-run=xxxxxMatchNothingxxxxx -test.benchtime=1ms -bench=.
 test-short:   ARGS=-short
 test-verbose: ARGS=-v -race
+test-concurrent-safe: ARGS=-run=ConcurrentSafe -count=100 -race
+test-concurrent-safe: TIMEOUT=120
 $(TEST_TARGETS): test
 test: $(OTEL_GO_MOD_DIRS:%=test/%)
 test/%: DIR=$*
@@ -236,6 +235,16 @@ govulncheck/%: $(GOVULNCHECK)
 codespell: $(CODESPELL)
 	@$(DOCKERPY) $(CODESPELL)
 
+.PHONY: toolchain-check
+toolchain-check:
+	@toolchainRes=$$(for f in $(ALL_GO_MOD_DIRS); do \
+	           awk '/^toolchain/ { found=1; next } END { if (found) print FILENAME }' $$f/go.mod; \
+	done); \
+	if [ -n "$${toolchainRes}" ]; then \
+			echo "toolchain checking failed:"; echo "$${toolchainRes}"; \
+			exit 1; \
+	fi
+
 .PHONY: license-check
 license-check:
 	@licRes=$$(for f in $$(find . -type f \( -iname '*.go' -o -iname '*.sh' \) ! -path '**/third_party/*' ! -path './.git/*' ) ; do \
@@ -261,7 +270,7 @@ SEMCONVPKG ?= "semconv/"
 semconv-generate: $(SEMCONVGEN) $(SEMCONVKIT)
 	[ "$(TAG)" ] || ( echo "TAG unset: missing opentelemetry semantic-conventions tag"; exit 1 )
 	[ "$(OTEL_SEMCONV_REPO)" ] || ( echo "OTEL_SEMCONV_REPO unset: missing path to opentelemetry semantic-conventions repo"; exit 1 )
-	$(SEMCONVGEN) -i "$(OTEL_SEMCONV_REPO)/model/." --only=attribute_group -p conventionType=trace -f attribute_group.go -t "$(SEMCONVPKG)/template.j2" -s "$(TAG)"
+	$(SEMCONVGEN) -i "$(OTEL_SEMCONV_REPO)/model/." --only=attribute_group -p conventionType=trace -f attribute_group.go -z "$(SEMCONVPKG)/capitalizations.txt" -t "$(SEMCONVPKG)/template.j2" -s "$(TAG)"
 	$(SEMCONVGEN) -i "$(OTEL_SEMCONV_REPO)/model/." --only=metric  -f metric.go -t "$(SEMCONVPKG)/metric_template.j2" -s "$(TAG)"
 	$(SEMCONVKIT) -output "$(SEMCONVPKG)/$(TAG)" -tag "$(TAG)"
 

vendor/go.opentelemetry.io/otel/README.md

@@ -1,6 +1,6 @@
 # OpenTelemetry-Go
 
-[![CI](https://github.com/open-telemetry/opentelemetry-go/workflows/ci/badge.svg)](https://github.com/open-telemetry/opentelemetry-go/actions?query=workflow%3Aci+branch%3Amain)
+[![ci](https://github.com/open-telemetry/opentelemetry-go/actions/workflows/ci.yml/badge.svg?branch=main)](https://github.com/open-telemetry/opentelemetry-go/actions/workflows/ci.yml)
 [![codecov.io](https://codecov.io/gh/open-telemetry/opentelemetry-go/coverage.svg?branch=main)](https://app.codecov.io/gh/open-telemetry/opentelemetry-go?branch=main)
 [![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel)](https://pkg.go.dev/go.opentelemetry.io/otel)
 [![Go Report Card](https://goreportcard.com/badge/go.opentelemetry.io/otel)](https://goreportcard.com/report/go.opentelemetry.io/otel)
@@ -51,25 +51,18 @@ Currently, this project supports the following environments.
 |----------|------------|--------------|
 | Ubuntu   | 1.23       | amd64        |
 | Ubuntu   | 1.22       | amd64        |
-| Ubuntu   | 1.21       | amd64        |
 | Ubuntu   | 1.23       | 386          |
 | Ubuntu   | 1.22       | 386          |
-| Ubuntu   | 1.21       | 386          |
 | Linux    | 1.23       | arm64        |
 | Linux    | 1.22       | arm64        |
-| Linux    | 1.21       | arm64        |
 | macOS 13 | 1.23       | amd64        |
 | macOS 13 | 1.22       | amd64        |
-| macOS 13 | 1.21       | amd64        |
 | macOS    | 1.23       | arm64        |
 | macOS    | 1.22       | arm64        |
-| macOS    | 1.21       | arm64        |
 | Windows  | 1.23       | amd64        |
 | Windows  | 1.22       | amd64        |
-| Windows  | 1.21       | amd64        |
 | Windows  | 1.23       | 386          |
 | Windows  | 1.22       | 386          |
-| Windows  | 1.21       | 386          |
 
 While this project should work for other systems, no compatibility guarantees
 are made for those systems currently.
@@ -96,8 +89,8 @@ If you need to extend the telemetry an instrumentation library provides or want
 to build your own instrumentation for your application directly you will need
 to use the
 [Go otel](https://pkg.go.dev/go.opentelemetry.io/otel)
-package. The included [examples](./example/) are a good way to see some
-practical uses of this process.
+package. The [examples](https://github.com/open-telemetry/opentelemetry-go-contrib/tree/main/examples)
+are a good way to see some practical uses of this process.
 
 ### Export
 

vendor/go.opentelemetry.io/otel/RELEASING.md

@@ -111,17 +111,6 @@ It is critical you make sure the version you push upstream is correct.
 Finally create a Release for the new `<new tag>` on GitHub.
 The release body should include all the release notes from the Changelog for this release.
 
-## Verify Examples
-
-After releasing verify that examples build outside of the repository.
-
-```
-./verify_examples.sh
-```
-
-The script copies examples into a different directory removes any `replace` declarations in `go.mod` and builds them.
-This ensures they build with the published release, not the local copy.
-
 ## Post-Release
 
 ### Contrib Repository
@@ -141,6 +130,6 @@ Importantly, bump any package versions referenced to be the latest one you just
 
 Bump the dependencies in the following Go services:
 
-- [`accountingservice`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/accountingservice)
-- [`checkoutservice`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/checkoutservice)
-- [`productcatalogservice`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/productcatalogservice)
+- [`accounting`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/accounting)
+- [`checkoutservice`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/checkout)
+- [`productcatalogservice`](https://github.com/open-telemetry/opentelemetry-demo/tree/main/src/product-catalog)

vendor/go.opentelemetry.io/otel/VERSIONING.md

@@ -26,7 +26,7 @@ is designed so the following goals can be achieved.
       go.opentelemetry.io/otel/v2 v2.0.1`) and in the package import path
       (e.g., `import "go.opentelemetry.io/otel/v2/trace"`). This includes the
       paths used in `go get` commands (e.g., `go get
-      go.opentelemetry.io/otel/v2@v2.0.1`.  Note there is both a `/v2` and a
+      go.opentelemetry.io/otel/v2@v2.0.1`).  Note there is both a `/v2` and a
       `@v2.0.1` in that example. One way to think about it is that the module
       name now includes the `/v2`, so include `/v2` whenever you are using the
       module name).

vendor/go.opentelemetry.io/otel/attribute/set.go

@@ -347,45 +347,25 @@ func computeDistinct(kvs []KeyValue) Distinct {
 func computeDistinctFixed(kvs []KeyValue) interface{} {
 	switch len(kvs) {
 	case 1:
-		ptr := new([1]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [1]KeyValue(kvs)
 	case 2:
-		ptr := new([2]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [2]KeyValue(kvs)
 	case 3:
-		ptr := new([3]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [3]KeyValue(kvs)
 	case 4:
-		ptr := new([4]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [4]KeyValue(kvs)
 	case 5:
-		ptr := new([5]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [5]KeyValue(kvs)
 	case 6:
-		ptr := new([6]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [6]KeyValue(kvs)
 	case 7:
-		ptr := new([7]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [7]KeyValue(kvs)
 	case 8:
-		ptr := new([8]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [8]KeyValue(kvs)
 	case 9:
-		ptr := new([9]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [9]KeyValue(kvs)
 	case 10:
-		ptr := new([10]KeyValue)
-		copy((*ptr)[:], kvs)
-		return *ptr
+		return [10]KeyValue(kvs)
 	default:
 		return nil
 	}

vendor/go.opentelemetry.io/otel/baggage/baggage.go

@@ -50,7 +50,7 @@ type Property struct {
 // component boundaries may impose their own restrictions on Property key.
 // For example, the W3C Baggage specification restricts the Property keys to strings that
 // satisfy the token definition from RFC7230, Section 3.2.6.
-// For maximum compatibility, alpha-numeric value are strongly recommended to be used as Property key.
+// For maximum compatibility, alphanumeric value are strongly recommended to be used as Property key.
 func NewKeyProperty(key string) (Property, error) {
 	if !validateBaggageName(key) {
 		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
@@ -90,7 +90,7 @@ func NewKeyValueProperty(key, value string) (Property, error) {
 // component boundaries may impose their own restrictions on Property key.
 // For example, the W3C Baggage specification restricts the Property keys to strings that
 // satisfy the token definition from RFC7230, Section 3.2.6.
-// For maximum compatibility, alpha-numeric value are strongly recommended to be used as Property key.
+// For maximum compatibility, alphanumeric value are strongly recommended to be used as Property key.
 func NewKeyValuePropertyRaw(key, value string) (Property, error) {
 	if !validateBaggageName(key) {
 		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
@@ -287,7 +287,7 @@ func NewMember(key, value string, props ...Property) (Member, error) {
 // component boundaries may impose their own restrictions on baggage key.
 // For example, the W3C Baggage specification restricts the baggage keys to strings that
 // satisfy the token definition from RFC7230, Section 3.2.6.
-// For maximum compatibility, alpha-numeric value are strongly recommended to be used as baggage key.
+// For maximum compatibility, alphanumeric value are strongly recommended to be used as baggage key.
 func NewMemberRaw(key, value string, props ...Property) (Member, error) {
 	m := Member{
 		key:        key,
@@ -355,7 +355,7 @@ func parseMember(member string) (Member, error) {
 }
 
 // replaceInvalidUTF8Sequences replaces invalid UTF-8 sequences with '<27>'.
-func replaceInvalidUTF8Sequences(cap int, unescapeVal string) string {
+func replaceInvalidUTF8Sequences(c int, unescapeVal string) string {
 	if utf8.ValidString(unescapeVal) {
 		return unescapeVal
 	}
@@ -363,7 +363,7 @@ func replaceInvalidUTF8Sequences(cap int, unescapeVal string) string {
 	// https://github.com/w3c/baggage/blob/8c215efbeebd3fa4b1aceb937a747e56444f22f3/baggage/HTTP_HEADER_FORMAT.md?plain=1#L69
 
 	var b strings.Builder
-	b.Grow(cap)
+	b.Grow(c)
 	for i := 0; i < len(unescapeVal); {
 		r, size := utf8.DecodeRuneInString(unescapeVal[i:])
 		if r == utf8.RuneError && size == 1 {

vendor/go.opentelemetry.io/otel/codes/codes.go

@@ -5,6 +5,7 @@ package codes // import "go.opentelemetry.io/otel/codes"
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"strconv"
 )
@@ -63,7 +64,7 @@ func (c *Code) UnmarshalJSON(b []byte) error {
 		return nil
 	}
 	if c == nil {
-		return fmt.Errorf("nil receiver passed to UnmarshalJSON")
+		return errors.New("nil receiver passed to UnmarshalJSON")
 	}
 
 	var x interface{}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/instrumentation.go

@@ -13,7 +13,8 @@ func InstrumentationScope(il instrumentation.Scope) *commonpb.InstrumentationSco
 		return nil
 	}
 	return &commonpb.InstrumentationScope{
-		Name:    il.Name,
-		Version: il.Version,
+		Name:       il.Name,
+		Version:    il.Version,
+		Attributes: Iterator(il.Attributes.Iter()),
 	}
 }

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform/span.go

@@ -97,8 +97,8 @@ func span(sd tracesdk.ReadOnlySpan) *tracepb.Span {
 		SpanId:                 sid[:],
 		TraceState:             sd.SpanContext().TraceState().String(),
 		Status:                 status(sd.Status().Code, sd.Status().Description),
-		StartTimeUnixNano:      uint64(sd.StartTime().UnixNano()),
-		EndTimeUnixNano:        uint64(sd.EndTime().UnixNano()),
+		StartTimeUnixNano:      uint64(max(0, sd.StartTime().UnixNano())), // nolint:gosec // Overflow checked.
+		EndTimeUnixNano:        uint64(max(0, sd.EndTime().UnixNano())),   // nolint:gosec // Overflow checked.
 		Links:                  links(sd.Links()),
 		Kind:                   spanKind(sd.SpanKind()),
 		Name:                   sd.Name(),
@@ -178,7 +178,7 @@ func buildSpanFlags(sc trace.SpanContext) uint32 {
 		flags |= tracepb.SpanFlags_SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
 	}
 
-	return uint32(flags)
+	return uint32(flags) // nolint:gosec // Flags is a bitmask and can't be negative
 }
 
 // spanEvents transforms span Events to an OTLP span events.
@@ -192,7 +192,7 @@ func spanEvents(es []tracesdk.Event) []*tracepb.Span_Event {
 	for i := 0; i < len(es); i++ {
 		events[i] = &tracepb.Span_Event{
 			Name:                   es[i].Name,
-			TimeUnixNano:           uint64(es[i].Time.UnixNano()),
+			TimeUnixNano:           uint64(max(0, es[i].Time.UnixNano())), // nolint:gosec // Overflow checked.
 			Attributes:             KeyValues(es[i].Attributes),
 			DroppedAttributesCount: clampUint32(es[i].DroppedAttributeCount),
 		}

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc/client.go

@@ -229,7 +229,12 @@ func (c *client) exportContext(parent context.Context) (context.Context, context
 	}
 
 	if c.metadata.Len() > 0 {
-		ctx = metadata.NewOutgoingContext(ctx, c.metadata)
+		md := c.metadata
+		if outMD, ok := metadata.FromOutgoingContext(ctx); ok {
+			md = metadata.Join(md, outMD)
+		}
+
+		ctx = metadata.NewOutgoingContext(ctx, md)
 	}
 
 	// Unify the client stopCtx with the parent.
@@ -289,7 +294,7 @@ func (c *client) MarshalLog() interface{} {
 		Type     string
 		Endpoint string
 	}{
-		Type:     "otlphttpgrpc",
+		Type:     "otlptracegrpc",
 		Endpoint: c.endpoint,
 	}
 }

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc/internal/otlpconfig/options.go

@@ -98,7 +98,7 @@ func cleanPath(urlPath string, defaultPath string) string {
 		return defaultPath
 	}
 	if !path.IsAbs(tmp) {
-		tmp = fmt.Sprintf("/%s", tmp)
+		tmp = "/" + tmp
 	}
 	return tmp
 }
@@ -125,7 +125,7 @@ func NewGRPCConfig(opts ...GRPCOption) Config {
 	if cfg.ServiceConfig != "" {
 		cfg.DialOptions = append(cfg.DialOptions, grpc.WithDefaultServiceConfig(cfg.ServiceConfig))
 	}
-	// Priroritize GRPCCredentials over Insecure (passing both is an error).
+	// Prioritize GRPCCredentials over Insecure (passing both is an error).
 	if cfg.Traces.GRPCCredentials != nil {
 		cfg.DialOptions = append(cfg.DialOptions, grpc.WithTransportCredentials(cfg.Traces.GRPCCredentials))
 	} else if cfg.Traces.Insecure {
@@ -278,9 +278,7 @@ func WithEndpointURL(v string) GenericOption {
 
 		cfg.Traces.Endpoint = u.Host
 		cfg.Traces.URLPath = u.Path
-		if u.Scheme != "https" {
-			cfg.Traces.Insecure = true
-		}
+		cfg.Traces.Insecure = u.Scheme != "https"
 
 		return cfg
 	})

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/client.go

@@ -166,8 +166,7 @@ func (d *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.Resourc
 			}()
 		}
 
-		switch sc := resp.StatusCode; {
-		case sc >= 200 && sc <= 299:
+		if sc := resp.StatusCode; sc >= 200 && sc <= 299 {
 			// Success, do not retry.
 			// Read the partial success message, if any.
 			var respData bytes.Buffer
@@ -194,34 +193,33 @@ func (d *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.Resourc
 				}
 			}
 			return nil
+		}
+		// Error cases.
 
-		case sc == http.StatusTooManyRequests,
-			sc == http.StatusBadGateway,
-			sc == http.StatusServiceUnavailable,
-			sc == http.StatusGatewayTimeout:
-			// Retry-able failures.
-			rErr := newResponseError(resp.Header, nil)
+		// server may return a message with the response
+		// body, so we read it to include in the error
+		// message to be returned. It will help in
+		// debugging the actual issue.
+		var respData bytes.Buffer
+		if _, err := io.Copy(&respData, resp.Body); err != nil {
+			return err
+		}
+		respStr := strings.TrimSpace(respData.String())
+		if len(respStr) == 0 {
+			respStr = "(empty)"
+		}
+		bodyErr := fmt.Errorf("body: %s", respStr)
 
-			// server may return a message with the response
-			// body, so we read it to include in the error
-			// message to be returned. It will help in
-			// debugging the actual issue.
-			var respData bytes.Buffer
-			if _, err := io.Copy(&respData, resp.Body); err != nil {
-				_ = resp.Body.Close()
-				return err
-			}
-
-			// overwrite the error message with the response body
-			// if it is not empty
-			if respStr := strings.TrimSpace(respData.String()); respStr != "" {
-				// Include response for context.
-				e := errors.New(respStr)
-				rErr = newResponseError(resp.Header, e)
-			}
-			return rErr
+		switch resp.StatusCode {
+		case http.StatusTooManyRequests,
+			http.StatusBadGateway,
+			http.StatusServiceUnavailable,
+			http.StatusGatewayTimeout:
+			// Retryable failure.
+			return newResponseError(resp.Header, bodyErr)
 		default:
-			return fmt.Errorf("failed to send to %s: %s", request.URL, resp.Status)
+			// Non-retryable failure.
+			return fmt.Errorf("failed to send to %s: %s (%w)", request.URL, resp.Status, bodyErr)
 		}
 	})
 }
@@ -278,7 +276,7 @@ func (d *client) MarshalLog() interface{} {
 		Endpoint string
 		Insecure bool
 	}{
-		Type:     "otlphttphttp",
+		Type:     "otlptracehttp",
 		Endpoint: d.cfg.Endpoint,
 		Insecure: d.cfg.Insecure,
 	}
@@ -328,7 +326,7 @@ func newResponseError(header http.Header, wrapped error) error {
 
 func (e retryableError) Error() string {
 	if e.err != nil {
-		return fmt.Sprintf("retry-able request failure: %s", e.err.Error())
+		return "retry-able request failure: " + e.err.Error()
 	}
 
 	return "retry-able request failure"

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/doc.go

@@ -22,7 +22,7 @@ target URL to which the exporter sends telemetry.
 The value must contain a scheme ("http" or "https") and host.
 The value may additionally contain a port and a path.
 The value should not contain a query string or fragment.
-The configuration can be overridden by [WithEndpoint], [WithEndpointURL], [WitnInsecure], and [WithURLPath] options.
+The configuration can be overridden by [WithEndpoint], [WithEndpointURL], [WithInsecure], and [WithURLPath] options.
 
 OTEL_EXPORTER_OTLP_HEADERS, OTEL_EXPORTER_OTLP_TRACES_HEADERS (default: none) -
 key-value pairs used as headers associated with HTTP requests.

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig/options.go

@@ -98,7 +98,7 @@ func cleanPath(urlPath string, defaultPath string) string {
 		return defaultPath
 	}
 	if !path.IsAbs(tmp) {
-		tmp = fmt.Sprintf("/%s", tmp)
+		tmp = "/" + tmp
 	}
 	return tmp
 }
@@ -125,7 +125,7 @@ func NewGRPCConfig(opts ...GRPCOption) Config {
 	if cfg.ServiceConfig != "" {
 		cfg.DialOptions = append(cfg.DialOptions, grpc.WithDefaultServiceConfig(cfg.ServiceConfig))
 	}
-	// Priroritize GRPCCredentials over Insecure (passing both is an error).
+	// Prioritize GRPCCredentials over Insecure (passing both is an error).
 	if cfg.Traces.GRPCCredentials != nil {
 		cfg.DialOptions = append(cfg.DialOptions, grpc.WithTransportCredentials(cfg.Traces.GRPCCredentials))
 	} else if cfg.Traces.Insecure {
@@ -278,9 +278,7 @@ func WithEndpointURL(v string) GenericOption {
 
 		cfg.Traces.Endpoint = u.Host
 		cfg.Traces.URLPath = u.Path
-		if u.Scheme != "https" {
-			cfg.Traces.Insecure = true
-		}
+		cfg.Traces.Insecure = u.Scheme != "https"
 
 		return cfg
 	})

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/version.go

@@ -5,5 +5,5 @@ package otlptrace // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace"
 
 // Version is the current release version of the OpenTelemetry OTLP trace exporter in use.
 func Version() string {
-	return "1.29.0"
+	return "1.34.0"
 }

vendor/go.opentelemetry.io/otel/exporters/prometheus/config.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/common/model"
 
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/sdk/metric"
@@ -131,7 +132,10 @@ func WithoutScopeInfo() Option {
 // have special behavior based on their name.
 func WithNamespace(ns string) Option {
 	return optionFunc(func(cfg config) config {
-		ns = sanitizeName(ns)
+		if model.NameValidationScheme != model.UTF8Validation {
+			// Only sanitize if prometheus does not support UTF-8.
+			ns = model.EscapeName(ns, model.NameEscapingScheme)
+		}
 		if !strings.HasSuffix(ns, "_") {
 			// namespace and metric names should be separated with an underscore,
 			// adds a trailing underscore if there is not one already.

vendor/go.opentelemetry.io/otel/exporters/prometheus/exporter.go

@@ -11,11 +11,10 @@ import (
 	"slices"
 	"strings"
 	"sync"
-	"unicode"
-	"unicode/utf8"
 
 	"github.com/prometheus/client_golang/prometheus"
 	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/model"
 	"google.golang.org/protobuf/proto"
 
 	"go.opentelemetry.io/otel"
@@ -34,15 +33,14 @@ const (
 	scopeInfoMetricName  = "otel_scope_info"
 	scopeInfoDescription = "Instrumentation Scope metadata"
 
+	scopeNameLabel    = "otel_scope_name"
+	scopeVersionLabel = "otel_scope_version"
+
 	traceIDExemplarKey = "trace_id"
 	spanIDExemplarKey  = "span_id"
 )
 
-var (
-	scopeInfoKeys = [2]string{"otel_scope_name", "otel_scope_version"}
-
-	errScopeInvalid = errors.New("invalid scope")
-)
+var errScopeInvalid = errors.New("invalid scope")
 
 // Exporter is a Prometheus Exporter that embeds the OTel metric.Reader
 // interface for easy instantiation with a MeterProvider.
@@ -188,7 +186,11 @@ func (c *collector) Collect(ch chan<- prometheus.Metric) {
 	}
 
 	for _, scopeMetrics := range metrics.ScopeMetrics {
-		var keys, values [2]string
+		n := len(c.resourceKeyVals.keys) + 2 // resource attrs + scope name + scope version
+		kv := keyVals{
+			keys: make([]string, 0, n),
+			vals: make([]string, 0, n),
+		}
 
 		if !c.disableScopeInfo {
 			scopeInfo, err := c.scopeInfo(scopeMetrics.Scope)
@@ -203,10 +205,13 @@ func (c *collector) Collect(ch chan<- prometheus.Metric) {
 
 			ch <- scopeInfo
 
-			keys = scopeInfoKeys
-			values = [2]string{scopeMetrics.Scope.Name, scopeMetrics.Scope.Version}
+			kv.keys = append(kv.keys, scopeNameLabel, scopeVersionLabel)
+			kv.vals = append(kv.vals, scopeMetrics.Scope.Name, scopeMetrics.Scope.Version)
 		}
 
+		kv.keys = append(kv.keys, c.resourceKeyVals.keys...)
+		kv.vals = append(kv.vals, c.resourceKeyVals.vals...)
+
 		for _, m := range scopeMetrics.Metrics {
 			typ := c.metricType(m)
 			if typ == nil {
@@ -225,25 +230,27 @@ func (c *collector) Collect(ch chan<- prometheus.Metric) {
 
 			switch v := m.Data.(type) {
 			case metricdata.Histogram[int64]:
-				addHistogramMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addHistogramMetric(ch, v, m, name, kv)
 			case metricdata.Histogram[float64]:
-				addHistogramMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addHistogramMetric(ch, v, m, name, kv)
 			case metricdata.Sum[int64]:
-				addSumMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addSumMetric(ch, v, m, name, kv)
 			case metricdata.Sum[float64]:
-				addSumMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addSumMetric(ch, v, m, name, kv)
 			case metricdata.Gauge[int64]:
-				addGaugeMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addGaugeMetric(ch, v, m, name, kv)
 			case metricdata.Gauge[float64]:
-				addGaugeMetric(ch, v, m, keys, values, name, c.resourceKeyVals)
+				addGaugeMetric(ch, v, m, name, kv)
 			}
 		}
 	}
 }
 
-func addHistogramMetric[N int64 | float64](ch chan<- prometheus.Metric, histogram metricdata.Histogram[N], m metricdata.Metrics, ks, vs [2]string, name string, resourceKV keyVals) {
+func addHistogramMetric[N int64 | float64](ch chan<- prometheus.Metric, histogram metricdata.Histogram[N], m metricdata.Metrics, name string, kv keyVals) {
 	for _, dp := range histogram.DataPoints {
-		keys, values := getAttrs(dp.Attributes, ks, vs, resourceKV)
+		keys, values := getAttrs(dp.Attributes)
+		keys = append(keys, kv.keys...)
+		values = append(values, kv.vals...)
 
 		desc := prometheus.NewDesc(name, m.Description, keys, nil)
 		buckets := make(map[float64]uint64, len(dp.Bounds))
@@ -263,14 +270,16 @@ func addHistogramMetric[N int64 | float64](ch chan<- prometheus.Metric, histogra
 	}
 }
 
-func addSumMetric[N int64 | float64](ch chan<- prometheus.Metric, sum metricdata.Sum[N], m metricdata.Metrics, ks, vs [2]string, name string, resourceKV keyVals) {
+func addSumMetric[N int64 | float64](ch chan<- prometheus.Metric, sum metricdata.Sum[N], m metricdata.Metrics, name string, kv keyVals) {
 	valueType := prometheus.CounterValue
 	if !sum.IsMonotonic {
 		valueType = prometheus.GaugeValue
 	}
 
 	for _, dp := range sum.DataPoints {
-		keys, values := getAttrs(dp.Attributes, ks, vs, resourceKV)
+		keys, values := getAttrs(dp.Attributes)
+		keys = append(keys, kv.keys...)
+		values = append(values, kv.vals...)
 
 		desc := prometheus.NewDesc(name, m.Description, keys, nil)
 		m, err := prometheus.NewConstMetric(desc, valueType, float64(dp.Value), values...)
@@ -278,14 +287,20 @@ func addSumMetric[N int64 | float64](ch chan<- prometheus.Metric, sum metricdata
 			otel.Handle(err)
 			continue
 		}
-		m = addExemplars(m, dp.Exemplars)
+		// GaugeValues don't support Exemplars at this time
+		// https://github.com/prometheus/client_golang/blob/aef8aedb4b6e1fb8ac1c90790645169125594096/prometheus/metric.go#L199
+		if valueType != prometheus.GaugeValue {
+			m = addExemplars(m, dp.Exemplars)
+		}
 		ch <- m
 	}
 }
 
-func addGaugeMetric[N int64 | float64](ch chan<- prometheus.Metric, gauge metricdata.Gauge[N], m metricdata.Metrics, ks, vs [2]string, name string, resourceKV keyVals) {
+func addGaugeMetric[N int64 | float64](ch chan<- prometheus.Metric, gauge metricdata.Gauge[N], m metricdata.Metrics, name string, kv keyVals) {
 	for _, dp := range gauge.DataPoints {
-		keys, values := getAttrs(dp.Attributes, ks, vs, resourceKV)
+		keys, values := getAttrs(dp.Attributes)
+		keys = append(keys, kv.keys...)
+		values = append(values, kv.vals...)
 
 		desc := prometheus.NewDesc(name, m.Description, keys, nil)
 		m, err := prometheus.NewConstMetric(desc, prometheus.GaugeValue, float64(dp.Value), values...)
@@ -297,61 +312,58 @@ func addGaugeMetric[N int64 | float64](ch chan<- prometheus.Metric, gauge metric
 	}
 }
 
-// getAttrs parses the attribute.Set to two lists of matching Prometheus-style
-// keys and values. It sanitizes invalid characters and handles duplicate keys
-// (due to sanitization) by sorting and concatenating the values following the spec.
-func getAttrs(attrs attribute.Set, ks, vs [2]string, resourceKV keyVals) ([]string, []string) {
-	keysMap := make(map[string][]string)
-	itr := attrs.Iter()
-	for itr.Next() {
-		kv := itr.Attribute()
-		key := strings.Map(sanitizeRune, string(kv.Key))
-		if _, ok := keysMap[key]; !ok {
-			keysMap[key] = []string{kv.Value.Emit()}
-		} else {
-			// if the sanitized key is a duplicate, append to the list of keys
-			keysMap[key] = append(keysMap[key], kv.Value.Emit())
-		}
-	}
-
+// getAttrs converts the attribute.Set to two lists of matching Prometheus-style
+// keys and values.
+func getAttrs(attrs attribute.Set) ([]string, []string) {
 	keys := make([]string, 0, attrs.Len())
 	values := make([]string, 0, attrs.Len())
-	for key, vals := range keysMap {
-		keys = append(keys, key)
-		slices.Sort(vals)
-		values = append(values, strings.Join(vals, ";"))
-	}
+	itr := attrs.Iter()
 
-	if ks[0] != "" {
-		keys = append(keys, ks[:]...)
-		values = append(values, vs[:]...)
+	if model.NameValidationScheme == model.UTF8Validation {
+		// Do not perform sanitization if prometheus supports UTF-8.
+		for itr.Next() {
+			kv := itr.Attribute()
+			keys = append(keys, string(kv.Key))
+			values = append(values, kv.Value.Emit())
+		}
+	} else {
+		// It sanitizes invalid characters and handles duplicate keys
+		// (due to sanitization) by sorting and concatenating the values following the spec.
+		keysMap := make(map[string][]string)
+		for itr.Next() {
+			kv := itr.Attribute()
+			key := model.EscapeName(string(kv.Key), model.NameEscapingScheme)
+			if _, ok := keysMap[key]; !ok {
+				keysMap[key] = []string{kv.Value.Emit()}
+			} else {
+				// if the sanitized key is a duplicate, append to the list of keys
+				keysMap[key] = append(keysMap[key], kv.Value.Emit())
+			}
+		}
+		for key, vals := range keysMap {
+			keys = append(keys, key)
+			slices.Sort(vals)
+			values = append(values, strings.Join(vals, ";"))
+		}
 	}
-
-	for idx := range resourceKV.keys {
-		keys = append(keys, resourceKV.keys[idx])
-		values = append(values, resourceKV.vals[idx])
-	}
-
 	return keys, values
 }
 
 func createInfoMetric(name, description string, res *resource.Resource) (prometheus.Metric, error) {
-	keys, values := getAttrs(*res.Set(), [2]string{}, [2]string{}, keyVals{})
+	keys, values := getAttrs(*res.Set())
 	desc := prometheus.NewDesc(name, description, keys, nil)
 	return prometheus.NewConstMetric(desc, prometheus.GaugeValue, float64(1), values...)
 }
 
 func createScopeInfoMetric(scope instrumentation.Scope) (prometheus.Metric, error) {
-	keys := scopeInfoKeys[:]
-	desc := prometheus.NewDesc(scopeInfoMetricName, scopeInfoDescription, keys, nil)
-	return prometheus.NewConstMetric(desc, prometheus.GaugeValue, float64(1), scope.Name, scope.Version)
-}
+	attrs := make([]attribute.KeyValue, 0, scope.Attributes.Len()+2) // resource attrs + scope name + scope version
+	attrs = append(attrs, scope.Attributes.ToSlice()...)
+	attrs = append(attrs, attribute.String(scopeNameLabel, scope.Name))
+	attrs = append(attrs, attribute.String(scopeVersionLabel, scope.Version))
 
-func sanitizeRune(r rune) rune {
-	if unicode.IsLetter(r) || unicode.IsDigit(r) || r == ':' || r == '_' {
-		return r
-	}
-	return '_'
+	keys, values := getAttrs(attribute.NewSet(attrs...))
+	desc := prometheus.NewDesc(scopeInfoMetricName, scopeInfoDescription, keys, nil)
+	return prometheus.NewConstMetric(desc, prometheus.GaugeValue, float64(1), values...)
 }
 
 var unitSuffixes = map[string]string{
@@ -392,7 +404,11 @@ var unitSuffixes = map[string]string{
 
 // getName returns the sanitized name, prefixed with the namespace and suffixed with unit.
 func (c *collector) getName(m metricdata.Metrics, typ *dto.MetricType) string {
-	name := sanitizeName(m.Name)
+	name := m.Name
+	if model.NameValidationScheme != model.UTF8Validation {
+		// Only sanitize if prometheus does not support UTF-8.
+		name = model.EscapeName(name, model.NameEscapingScheme)
+	}
 	addCounterSuffix := !c.withoutCounterSuffixes && *typ == dto.MetricType_COUNTER
 	if addCounterSuffix {
 		// Remove the _total suffix here, as we will re-add the total suffix
@@ -411,59 +427,6 @@ func (c *collector) getName(m metricdata.Metrics, typ *dto.MetricType) string {
 	return name
 }
 
-func sanitizeName(n string) string {
-	// This algorithm is based on strings.Map from Go 1.19.
-	const replacement = '_'
-
-	valid := func(i int, r rune) bool {
-		// Taken from
-		// https://github.com/prometheus/common/blob/dfbc25bd00225c70aca0d94c3c4bb7744f28ace0/model/metric.go#L92-L102
-		if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') || r == '_' || r == ':' || (r >= '0' && r <= '9' && i > 0) {
-			return true
-		}
-		return false
-	}
-
-	// This output buffer b is initialized on demand, the first time a
-	// character needs to be replaced.
-	var b strings.Builder
-	for i, c := range n {
-		if valid(i, c) {
-			continue
-		}
-
-		if i == 0 && c >= '0' && c <= '9' {
-			// Prefix leading number with replacement character.
-			b.Grow(len(n) + 1)
-			_ = b.WriteByte(byte(replacement))
-			break
-		}
-		b.Grow(len(n))
-		_, _ = b.WriteString(n[:i])
-		_ = b.WriteByte(byte(replacement))
-		width := utf8.RuneLen(c)
-		n = n[i+width:]
-		break
-	}
-
-	// Fast path for unchanged input.
-	if b.Cap() == 0 { // b.Grow was not called above.
-		return n
-	}
-
-	for _, c := range n {
-		// Due to inlining, it is more performant to invoke WriteByte rather then
-		// WriteRune.
-		if valid(1, c) { // We are guaranteed to not be at the start.
-			_ = b.WriteByte(byte(c))
-		} else {
-			_ = b.WriteByte(byte(replacement))
-		}
-	}
-
-	return b.String()
-}
-
 func (c *collector) metricType(m metricdata.Metrics) *dto.MetricType {
 	switch v := m.Data.(type) {
 	case metricdata.Histogram[int64], metricdata.Histogram[float64]:
@@ -489,7 +452,7 @@ func (c *collector) createResourceAttributes(res *resource.Resource) {
 	defer c.mu.Unlock()
 
 	resourceAttrs, _ := res.Set().Filter(c.resourceAttributesFilter)
-	resourceKeys, resourceValues := getAttrs(resourceAttrs, [2]string{}, [2]string{}, keyVals{})
+	resourceKeys, resourceValues := getAttrs(resourceAttrs)
 	c.resourceKeyVals = keyVals{keys: resourceKeys, vals: resourceValues}
 }
 
@@ -584,7 +547,8 @@ func addExemplars[N int64 | float64](m prometheus.Metric, exemplars []metricdata
 func attributesToLabels(attrs []attribute.KeyValue) prometheus.Labels {
 	labels := make(map[string]string)
 	for _, attr := range attrs {
-		labels[string(attr.Key)] = attr.Value.Emit()
+		key := model.EscapeName(string(attr.Key), model.NameEscapingScheme)
+		labels[key] = attr.Value.Emit()
 	}
 	return labels
 }

vendor/go.opentelemetry.io/otel/internal/attribute/attribute.go

@@ -49,12 +49,11 @@ func AsBoolSlice(v interface{}) []bool {
 	if rv.Type().Kind() != reflect.Array {
 		return nil
 	}
-	var zero bool
-	correctLen := rv.Len()
-	correctType := reflect.ArrayOf(correctLen, reflect.TypeOf(zero))
-	cpy := reflect.New(correctType)
-	_ = reflect.Copy(cpy.Elem(), rv)
-	return cpy.Elem().Slice(0, correctLen).Interface().([]bool)
+	cpy := make([]bool, rv.Len())
+	if len(cpy) > 0 {
+		_ = reflect.Copy(reflect.ValueOf(cpy), rv)
+	}
+	return cpy
 }
 
 // AsInt64Slice converts an int64 array into a slice into with same elements as array.
@@ -63,12 +62,11 @@ func AsInt64Slice(v interface{}) []int64 {
 	if rv.Type().Kind() != reflect.Array {
 		return nil
 	}
-	var zero int64
-	correctLen := rv.Len()
-	correctType := reflect.ArrayOf(correctLen, reflect.TypeOf(zero))
-	cpy := reflect.New(correctType)
-	_ = reflect.Copy(cpy.Elem(), rv)
-	return cpy.Elem().Slice(0, correctLen).Interface().([]int64)
+	cpy := make([]int64, rv.Len())
+	if len(cpy) > 0 {
+		_ = reflect.Copy(reflect.ValueOf(cpy), rv)
+	}
+	return cpy
 }
 
 // AsFloat64Slice converts a float64 array into a slice into with same elements as array.
@@ -77,12 +75,11 @@ func AsFloat64Slice(v interface{}) []float64 {
 	if rv.Type().Kind() != reflect.Array {
 		return nil
 	}
-	var zero float64
-	correctLen := rv.Len()
-	correctType := reflect.ArrayOf(correctLen, reflect.TypeOf(zero))
-	cpy := reflect.New(correctType)
-	_ = reflect.Copy(cpy.Elem(), rv)
-	return cpy.Elem().Slice(0, correctLen).Interface().([]float64)
+	cpy := make([]float64, rv.Len())
+	if len(cpy) > 0 {
+		_ = reflect.Copy(reflect.ValueOf(cpy), rv)
+	}
+	return cpy
 }
 
 // AsStringSlice converts a string array into a slice into with same elements as array.
@@ -91,10 +88,9 @@ func AsStringSlice(v interface{}) []string {
 	if rv.Type().Kind() != reflect.Array {
 		return nil
 	}
-	var zero string
-	correctLen := rv.Len()
-	correctType := reflect.ArrayOf(correctLen, reflect.TypeOf(zero))
-	cpy := reflect.New(correctType)
-	_ = reflect.Copy(cpy.Elem(), rv)
-	return cpy.Elem().Slice(0, correctLen).Interface().([]string)
+	cpy := make([]string, rv.Len())
+	if len(cpy) > 0 {
+		_ = reflect.Copy(reflect.ValueOf(cpy), rv)
+	}
+	return cpy
 }

vendor/go.opentelemetry.io/otel/internal/global/instruments.go

@@ -13,7 +13,7 @@ import (
 
 // unwrapper unwraps to return the underlying instrument implementation.
 type unwrapper interface {
-	Unwrap() metric.Observable
+	unwrap() metric.Observable
 }
 
 type afCounter struct {
@@ -40,7 +40,7 @@ func (i *afCounter) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *afCounter) Unwrap() metric.Observable {
+func (i *afCounter) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Float64ObservableCounter)
 	}
@@ -71,7 +71,7 @@ func (i *afUpDownCounter) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *afUpDownCounter) Unwrap() metric.Observable {
+func (i *afUpDownCounter) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Float64ObservableUpDownCounter)
 	}
@@ -102,7 +102,7 @@ func (i *afGauge) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *afGauge) Unwrap() metric.Observable {
+func (i *afGauge) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Float64ObservableGauge)
 	}
@@ -133,7 +133,7 @@ func (i *aiCounter) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *aiCounter) Unwrap() metric.Observable {
+func (i *aiCounter) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Int64ObservableCounter)
 	}
@@ -164,7 +164,7 @@ func (i *aiUpDownCounter) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *aiUpDownCounter) Unwrap() metric.Observable {
+func (i *aiUpDownCounter) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Int64ObservableUpDownCounter)
 	}
@@ -195,7 +195,7 @@ func (i *aiGauge) setDelegate(m metric.Meter) {
 	i.delegate.Store(ctr)
 }
 
-func (i *aiGauge) Unwrap() metric.Observable {
+func (i *aiGauge) unwrap() metric.Observable {
 	if ctr := i.delegate.Load(); ctr != nil {
 		return ctr.(metric.Int64ObservableGauge)
 	}

vendor/go.opentelemetry.io/otel/internal/global/meter.go

@@ -5,8 +5,9 @@ package global // import "go.opentelemetry.io/otel/internal/global"
 
 import (
 	"container/list"
+	"context"
+	"reflect"
 	"sync"
-	"sync/atomic"
 
 	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/metric/embedded"
@@ -66,6 +67,7 @@ func (p *meterProvider) Meter(name string, opts ...metric.MeterOption) metric.Me
 		name:    name,
 		version: c.InstrumentationVersion(),
 		schema:  c.SchemaURL(),
+		attrs:   c.InstrumentationAttributes(),
 	}
 
 	if p.meters == nil {
@@ -76,7 +78,7 @@ func (p *meterProvider) Meter(name string, opts ...metric.MeterOption) metric.Me
 		return val
 	}
 
-	t := &meter{name: name, opts: opts}
+	t := &meter{name: name, opts: opts, instruments: make(map[instID]delegatedInstrument)}
 	p.meters[key] = t
 	return t
 }
@@ -92,17 +94,29 @@ type meter struct {
 	opts []metric.MeterOption
 
 	mtx         sync.Mutex
-	instruments []delegatedInstrument
+	instruments map[instID]delegatedInstrument
 
 	registry list.List
 
-	delegate atomic.Value // metric.Meter
+	delegate metric.Meter
 }
 
 type delegatedInstrument interface {
 	setDelegate(metric.Meter)
 }
 
+// instID are the identifying properties of a instrument.
+type instID struct {
+	// name is the name of the stream.
+	name string
+	// description is the description of the stream.
+	description string
+	// kind defines the functional group of the instrument.
+	kind reflect.Type
+	// unit is the unit of the stream.
+	unit string
+}
+
 // setDelegate configures m to delegate all Meter functionality to Meters
 // created by provider.
 //
@@ -110,12 +124,12 @@ type delegatedInstrument interface {
 //
 // It is guaranteed by the caller that this happens only once.
 func (m *meter) setDelegate(provider metric.MeterProvider) {
-	meter := provider.Meter(m.name, m.opts...)
-	m.delegate.Store(meter)
-
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
+	meter := provider.Meter(m.name, m.opts...)
+	m.delegate = meter
+
 	for _, inst := range m.instruments {
 		inst.setDelegate(meter)
 	}
@@ -133,169 +147,336 @@ func (m *meter) setDelegate(provider metric.MeterProvider) {
 }
 
 func (m *meter) Int64Counter(name string, options ...metric.Int64CounterOption) (metric.Int64Counter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64Counter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64Counter(name, options...)
+	}
+
+	cfg := metric.NewInt64CounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*siCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64Counter), nil
+	}
 	i := &siCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64UpDownCounter(name string, options ...metric.Int64UpDownCounterOption) (metric.Int64UpDownCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64UpDownCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64UpDownCounter(name, options...)
+	}
+
+	cfg := metric.NewInt64UpDownCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*siUpDownCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64UpDownCounter), nil
+	}
 	i := &siUpDownCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64Histogram(name string, options ...metric.Int64HistogramOption) (metric.Int64Histogram, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64Histogram(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64Histogram(name, options...)
+	}
+
+	cfg := metric.NewInt64HistogramConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*siHistogram)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64Histogram), nil
+	}
 	i := &siHistogram{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64Gauge(name string, options ...metric.Int64GaugeOption) (metric.Int64Gauge, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64Gauge(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64Gauge(name, options...)
+	}
+
+	cfg := metric.NewInt64GaugeConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*siGauge)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64Gauge), nil
+	}
 	i := &siGauge{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64ObservableCounter(name string, options ...metric.Int64ObservableCounterOption) (metric.Int64ObservableCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64ObservableCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64ObservableCounter(name, options...)
+	}
+
+	cfg := metric.NewInt64ObservableCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*aiCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64ObservableCounter), nil
+	}
 	i := &aiCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64ObservableUpDownCounter(name string, options ...metric.Int64ObservableUpDownCounterOption) (metric.Int64ObservableUpDownCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64ObservableUpDownCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64ObservableUpDownCounter(name, options...)
+	}
+
+	cfg := metric.NewInt64ObservableUpDownCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*aiUpDownCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64ObservableUpDownCounter), nil
+	}
 	i := &aiUpDownCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Int64ObservableGauge(name string, options ...metric.Int64ObservableGaugeOption) (metric.Int64ObservableGauge, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Int64ObservableGauge(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Int64ObservableGauge(name, options...)
+	}
+
+	cfg := metric.NewInt64ObservableGaugeConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*aiGauge)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Int64ObservableGauge), nil
+	}
 	i := &aiGauge{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64Counter(name string, options ...metric.Float64CounterOption) (metric.Float64Counter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64Counter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64Counter(name, options...)
+	}
+
+	cfg := metric.NewFloat64CounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*sfCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64Counter), nil
+	}
 	i := &sfCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64UpDownCounter(name string, options ...metric.Float64UpDownCounterOption) (metric.Float64UpDownCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64UpDownCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64UpDownCounter(name, options...)
+	}
+
+	cfg := metric.NewFloat64UpDownCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*sfUpDownCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64UpDownCounter), nil
+	}
 	i := &sfUpDownCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64Histogram(name string, options ...metric.Float64HistogramOption) (metric.Float64Histogram, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64Histogram(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64Histogram(name, options...)
+	}
+
+	cfg := metric.NewFloat64HistogramConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*sfHistogram)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64Histogram), nil
+	}
 	i := &sfHistogram{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64Gauge(name string, options ...metric.Float64GaugeOption) (metric.Float64Gauge, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64Gauge(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64Gauge(name, options...)
+	}
+
+	cfg := metric.NewFloat64GaugeConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*sfGauge)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64Gauge), nil
+	}
 	i := &sfGauge{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64ObservableCounter(name string, options ...metric.Float64ObservableCounterOption) (metric.Float64ObservableCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64ObservableCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64ObservableCounter(name, options...)
+	}
+
+	cfg := metric.NewFloat64ObservableCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*afCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64ObservableCounter), nil
+	}
 	i := &afCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64ObservableUpDownCounter(name string, options ...metric.Float64ObservableUpDownCounterOption) (metric.Float64ObservableUpDownCounter, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64ObservableUpDownCounter(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64ObservableUpDownCounter(name, options...)
+	}
+
+	cfg := metric.NewFloat64ObservableUpDownCounterConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*afUpDownCounter)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64ObservableUpDownCounter), nil
+	}
 	i := &afUpDownCounter{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 func (m *meter) Float64ObservableGauge(name string, options ...metric.Float64ObservableGaugeOption) (metric.Float64ObservableGauge, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		return del.Float64ObservableGauge(name, options...)
-	}
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
+
+	if m.delegate != nil {
+		return m.delegate.Float64ObservableGauge(name, options...)
+	}
+
+	cfg := metric.NewFloat64ObservableGaugeConfig(options...)
+	id := instID{
+		name:        name,
+		kind:        reflect.TypeOf((*afGauge)(nil)),
+		description: cfg.Description(),
+		unit:        cfg.Unit(),
+	}
+	if f, ok := m.instruments[id]; ok {
+		return f.(metric.Float64ObservableGauge), nil
+	}
 	i := &afGauge{name: name, opts: options}
-	m.instruments = append(m.instruments, i)
+	m.instruments[id] = i
 	return i, nil
 }
 
 // RegisterCallback captures the function that will be called during Collect.
 func (m *meter) RegisterCallback(f metric.Callback, insts ...metric.Observable) (metric.Registration, error) {
-	if del, ok := m.delegate.Load().(metric.Meter); ok {
-		insts = unwrapInstruments(insts)
-		return del.RegisterCallback(f, insts...)
-	}
-
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
+	if m.delegate != nil {
+		return m.delegate.RegisterCallback(unwrapCallback(f), unwrapInstruments(insts)...)
+	}
+
 	reg := &registration{instruments: insts, function: f}
 	e := m.registry.PushBack(reg)
 	reg.unreg = func() error {
@@ -307,15 +488,11 @@ func (m *meter) RegisterCallback(f metric.Callback, insts ...metric.Observable)
 	return reg, nil
 }
 
-type wrapped interface {
-	unwrap() metric.Observable
-}
-
 func unwrapInstruments(instruments []metric.Observable) []metric.Observable {
 	out := make([]metric.Observable, 0, len(instruments))
 
 	for _, inst := range instruments {
-		if in, ok := inst.(wrapped); ok {
+		if in, ok := inst.(unwrapper); ok {
 			out = append(out, in.unwrap())
 		} else {
 			out = append(out, inst)
@@ -335,9 +512,61 @@ type registration struct {
 	unregMu sync.Mutex
 }
 
-func (c *registration) setDelegate(m metric.Meter) {
-	insts := unwrapInstruments(c.instruments)
+type unwrapObs struct {
+	embedded.Observer
+	obs metric.Observer
+}
 
+// unwrapFloat64Observable returns an expected metric.Float64Observable after
+// unwrapping the global object.
+func unwrapFloat64Observable(inst metric.Float64Observable) metric.Float64Observable {
+	if unwrapped, ok := inst.(unwrapper); ok {
+		if floatObs, ok := unwrapped.unwrap().(metric.Float64Observable); ok {
+			// Note: if the unwrapped object does not
+			// unwrap as an observable for either of the
+			// predicates here, it means an internal bug in
+			// this package.  We avoid logging an error in
+			// this case, because the SDK has to try its
+			// own type conversion on the object.  The SDK
+			// will see this and be forced to respond with
+			// its own error.
+			//
+			// This code uses a double-nested if statement
+			// to avoid creating a branch that is
+			// impossible to cover.
+			inst = floatObs
+		}
+	}
+	return inst
+}
+
+// unwrapInt64Observable returns an expected metric.Int64Observable after
+// unwrapping the global object.
+func unwrapInt64Observable(inst metric.Int64Observable) metric.Int64Observable {
+	if unwrapped, ok := inst.(unwrapper); ok {
+		if unint, ok := unwrapped.unwrap().(metric.Int64Observable); ok {
+			// See the comment in unwrapFloat64Observable().
+			inst = unint
+		}
+	}
+	return inst
+}
+
+func (uo *unwrapObs) ObserveFloat64(inst metric.Float64Observable, value float64, opts ...metric.ObserveOption) {
+	uo.obs.ObserveFloat64(unwrapFloat64Observable(inst), value, opts...)
+}
+
+func (uo *unwrapObs) ObserveInt64(inst metric.Int64Observable, value int64, opts ...metric.ObserveOption) {
+	uo.obs.ObserveInt64(unwrapInt64Observable(inst), value, opts...)
+}
+
+func unwrapCallback(f metric.Callback) metric.Callback {
+	return func(ctx context.Context, obs metric.Observer) error {
+		return f(ctx, &unwrapObs{obs: obs})
+	}
+}
+
+func (c *registration) setDelegate(m metric.Meter) {
 	c.unregMu.Lock()
 	defer c.unregMu.Unlock()
 
@@ -346,9 +575,10 @@ func (c *registration) setDelegate(m metric.Meter) {
 		return
 	}
 
-	reg, err := m.RegisterCallback(c.function, insts...)
+	reg, err := m.RegisterCallback(unwrapCallback(c.function), unwrapInstruments(c.instruments)...)
 	if err != nil {
 		GetErrorHandler().Handle(err)
+		return
 	}
 
 	c.unreg = reg.Unregister

vendor/go.opentelemetry.io/otel/internal/global/trace.go

@@ -25,6 +25,7 @@ import (
 	"sync"
 	"sync/atomic"
 
+	"go.opentelemetry.io/auto/sdk"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/trace"
@@ -87,6 +88,7 @@ func (p *tracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.T
 		name:    name,
 		version: c.InstrumentationVersion(),
 		schema:  c.SchemaURL(),
+		attrs:   c.InstrumentationAttributes(),
 	}
 
 	if p.tracers == nil {
@@ -102,7 +104,12 @@ func (p *tracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.T
 	return t
 }
 
-type il struct{ name, version, schema string }
+type il struct {
+	name    string
+	version string
+	schema  string
+	attrs   attribute.Set
+}
 
 // tracer is a placeholder for a trace.Tracer.
 //
@@ -139,6 +146,30 @@ func (t *tracer) Start(ctx context.Context, name string, opts ...trace.SpanStart
 		return delegate.(trace.Tracer).Start(ctx, name, opts...)
 	}
 
+	return t.newSpan(ctx, autoInstEnabled, name, opts)
+}
+
+// autoInstEnabled determines if the auto-instrumentation SDK span is returned
+// from the tracer when not backed by a delegate and auto-instrumentation has
+// attached to this process.
+//
+// The auto-instrumentation is expected to overwrite this value to true when it
+// attaches. By default, this will point to false and mean a tracer will return
+// a nonRecordingSpan by default.
+var autoInstEnabled = new(bool)
+
+func (t *tracer) newSpan(ctx context.Context, autoSpan *bool, name string, opts []trace.SpanStartOption) (context.Context, trace.Span) {
+	// autoInstEnabled is passed to newSpan via the autoSpan parameter. This is
+	// so the auto-instrumentation can define a uprobe for (*t).newSpan and be
+	// provided with the address of the bool autoInstEnabled points to. It
+	// needs to be a parameter so that pointer can be reliably determined, it
+	// should not be read from the global.
+
+	if *autoSpan {
+		tracer := sdk.TracerProvider().Tracer(t.name, t.opts...)
+		return tracer.Start(ctx, name, opts...)
+	}
+
 	s := nonRecordingSpan{sc: trace.SpanContextFromContext(ctx), tracer: t}
 	ctx = trace.ContextWithSpan(ctx, s)
 	return ctx, s

vendor/go.opentelemetry.io/otel/internal/rawhelpers.go

@@ -20,7 +20,8 @@ func RawToBool(r uint64) bool {
 }
 
 func Int64ToRaw(i int64) uint64 {
-	return uint64(i)
+	// Assumes original was a valid int64 (overflow not checked).
+	return uint64(i) // nolint: gosec
 }
 
 func RawToInt64(r uint64) int64 {

vendor/go.opentelemetry.io/otel/metric/asyncfloat64.go

@@ -213,7 +213,7 @@ type Float64Observer interface {
 }
 
 // Float64Callback is a function registered with a Meter that makes
-// observations for a Float64Observerable instrument it is registered with.
+// observations for a Float64Observable instrument it is registered with.
 // Calls to the Float64Observer record measurement values for the
 // Float64Observable.
 //

vendor/go.opentelemetry.io/otel/metric/asyncint64.go

@@ -212,7 +212,7 @@ type Int64Observer interface {
 }
 
 // Int64Callback is a function registered with a Meter that makes observations
-// for an Int64Observerable instrument it is registered with. Calls to the
+// for an Int64Observable instrument it is registered with. Calls to the
 // Int64Observer record measurement values for the Int64Observable.
 //
 // The function needs to complete in a finite amount of time and the deadline

vendor/go.opentelemetry.io/otel/metric/instrument.go

@@ -351,7 +351,7 @@ func WithAttributeSet(attributes attribute.Set) MeasurementOption {
 //
 //	cp := make([]attribute.KeyValue, len(attributes))
 //	copy(cp, attributes)
-//	WithAttributes(attribute.NewSet(cp...))
+//	WithAttributeSet(attribute.NewSet(cp...))
 //
 // [attribute.NewSet] may modify the passed attributes so this will make a copy
 // of attributes before creating a set in order to ensure this function is

vendor/go.opentelemetry.io/otel/renovate.json

@@ -15,10 +15,12 @@
       "enabled": true
     },
     {
-      "matchFileNames": ["internal/tools/**"],
-      "matchManagers": ["gomod"],
-      "matchDepTypes": ["indirect"],
-      "enabled": false
+      "matchPackageNames": ["google.golang.org/genproto/googleapis/**"],
+      "groupName": "googleapis"
+    },
+    {
+      "matchPackageNames": ["golang.org/x/**"],
+      "groupName": "golang.org/x"
     }
   ]
 }

vendor/go.opentelemetry.io/otel/sdk/instrumentation/scope.go

@@ -3,6 +3,8 @@
 
 package instrumentation // import "go.opentelemetry.io/otel/sdk/instrumentation"
 
+import "go.opentelemetry.io/otel/attribute"
+
 // Scope represents the instrumentation scope.
 type Scope struct {
 	// Name is the name of the instrumentation scope. This should be the
@@ -12,4 +14,6 @@ type Scope struct {
 	Version string
 	// SchemaURL of the telemetry emitted by the scope.
 	SchemaURL string
+	// Attributes of the telemetry emitted by the scope.
+	Attributes attribute.Set
 }

vendor/go.opentelemetry.io/otel/sdk/metric/config.go

@@ -5,17 +5,22 @@ package metric // import "go.opentelemetry.io/otel/sdk/metric"
 
 import (
 	"context"
-	"fmt"
+	"errors"
+	"os"
+	"strings"
 	"sync"
 
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
 	"go.opentelemetry.io/otel/sdk/resource"
 )
 
 // config contains configuration options for a MeterProvider.
 type config struct {
-	res     *resource.Resource
-	readers []Reader
-	views   []View
+	res            *resource.Resource
+	readers        []Reader
+	views          []View
+	exemplarFilter exemplar.Filter
 }
 
 // readerSignals returns a force-flush and shutdown function for a
@@ -39,25 +44,13 @@ func (c config) readerSignals() (forceFlush, shutdown func(context.Context) erro
 // value.
 func unify(funcs []func(context.Context) error) func(context.Context) error {
 	return func(ctx context.Context) error {
-		var errs []error
+		var err error
 		for _, f := range funcs {
-			if err := f(ctx); err != nil {
-				errs = append(errs, err)
+			if e := f(ctx); e != nil {
+				err = errors.Join(err, e)
 			}
 		}
-		return unifyErrors(errs)
-	}
-}
-
-// unifyErrors combines multiple errors into a single error.
-func unifyErrors(errs []error) error {
-	switch len(errs) {
-	case 0:
-		return nil
-	case 1:
-		return errs[0]
-	default:
-		return fmt.Errorf("%v", errs)
+		return err
 	}
 }
 
@@ -75,7 +68,13 @@ func unifyShutdown(funcs []func(context.Context) error) func(context.Context) er
 
 // newConfig returns a config configured with options.
 func newConfig(options []Option) config {
-	conf := config{res: resource.Default()}
+	conf := config{
+		res:            resource.Default(),
+		exemplarFilter: exemplar.TraceBasedFilter,
+	}
+	for _, o := range meterProviderOptionsFromEnv() {
+		conf = o.apply(conf)
+	}
 	for _, o := range options {
 		conf = o.apply(conf)
 	}
@@ -103,7 +102,11 @@ func (o optionFunc) apply(conf config) config {
 // go.opentelemetry.io/otel/sdk/resource package will be used.
 func WithResource(res *resource.Resource) Option {
 	return optionFunc(func(conf config) config {
-		conf.res = res
+		var err error
+		conf.res, err = resource.Merge(resource.Environment(), res)
+		if err != nil {
+			otel.Handle(err)
+		}
 		return conf
 	})
 }
@@ -135,3 +138,35 @@ func WithView(views ...View) Option {
 		return cfg
 	})
 }
+
+// WithExemplarFilter configures the exemplar filter.
+//
+// The exemplar filter determines which measurements are offered to the
+// exemplar reservoir, but the exemplar reservoir makes the final decision of
+// whether to store an exemplar.
+//
+// By default, the [exemplar.SampledFilter]
+// is used. Exemplars can be entirely disabled by providing the
+// [exemplar.AlwaysOffFilter].
+func WithExemplarFilter(filter exemplar.Filter) Option {
+	return optionFunc(func(cfg config) config {
+		cfg.exemplarFilter = filter
+		return cfg
+	})
+}
+
+func meterProviderOptionsFromEnv() []Option {
+	var opts []Option
+	// https://github.com/open-telemetry/opentelemetry-specification/blob/d4b241f451674e8f611bb589477680341006ad2b/specification/configuration/sdk-environment-variables.md#exemplar
+	const filterEnvKey = "OTEL_METRICS_EXEMPLAR_FILTER"
+
+	switch strings.ToLower(strings.TrimSpace(os.Getenv(filterEnvKey))) {
+	case "always_on":
+		opts = append(opts, WithExemplarFilter(exemplar.AlwaysOnFilter))
+	case "always_off":
+		opts = append(opts, WithExemplarFilter(exemplar.AlwaysOffFilter))
+	case "trace_based":
+		opts = append(opts, WithExemplarFilter(exemplar.TraceBasedFilter))
+	}
+	return opts
+}

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar.go

@@ -4,51 +4,49 @@
 package metric // import "go.opentelemetry.io/otel/sdk/metric"
 
 import (
-	"os"
 	"runtime"
-	"slices"
 
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
-	"go.opentelemetry.io/otel/sdk/metric/internal/x"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
+	"go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
 )
 
+// ExemplarReservoirProviderSelector selects the
+// [exemplar.ReservoirProvider] to use
+// based on the [Aggregation] of the metric.
+type ExemplarReservoirProviderSelector func(Aggregation) exemplar.ReservoirProvider
+
 // reservoirFunc returns the appropriately configured exemplar reservoir
-// creation func based on the passed InstrumentKind and user defined
-// environment variables.
+// creation func based on the passed InstrumentKind and filter configuration.
+func reservoirFunc[N int64 | float64](provider exemplar.ReservoirProvider, filter exemplar.Filter) func(attribute.Set) aggregate.FilteredExemplarReservoir[N] {
+	return func(attrs attribute.Set) aggregate.FilteredExemplarReservoir[N] {
+		return aggregate.NewFilteredExemplarReservoir[N](filter, provider(attrs))
+	}
+}
+
+// DefaultExemplarReservoirProviderSelector returns the default
+// [exemplar.ReservoirProvider] for the
+// provided [Aggregation].
 //
-// Note: This will only return non-nil values when the experimental exemplar
-// feature is enabled and the OTEL_METRICS_EXEMPLAR_FILTER environment variable
-// is not set to always_off.
-func reservoirFunc[N int64 | float64](agg Aggregation) func() exemplar.FilteredReservoir[N] {
-	if !x.Exemplars.Enabled() {
-		return nil
-	}
-	// https://github.com/open-telemetry/opentelemetry-specification/blob/d4b241f451674e8f611bb589477680341006ad2b/specification/configuration/sdk-environment-variables.md#exemplar
-	const filterEnvKey = "OTEL_METRICS_EXEMPLAR_FILTER"
-
-	var filter exemplar.Filter
-
-	switch os.Getenv(filterEnvKey) {
-	case "always_on":
-		filter = exemplar.AlwaysOnFilter
-	case "always_off":
-		return exemplar.Drop
-	case "trace_based":
-		fallthrough
-	default:
-		filter = exemplar.SampledFilter
-	}
-
+// For explicit bucket histograms with more than 1 bucket, it uses the
+// [exemplar.HistogramReservoirProvider].
+// For exponential histograms, it uses the
+// [exemplar.FixedSizeReservoirProvider]
+// with a size of min(20, max_buckets).
+// For all other aggregations, it uses the
+// [exemplar.FixedSizeReservoirProvider]
+// with a size equal to the number of CPUs.
+//
+// Exemplar default reservoirs MAY change in a minor version bump. No
+// guarantees are made on the shape or statistical properties of returned
+// exemplars.
+func DefaultExemplarReservoirProviderSelector(agg Aggregation) exemplar.ReservoirProvider {
 	// https://github.com/open-telemetry/opentelemetry-specification/blob/d4b241f451674e8f611bb589477680341006ad2b/specification/metrics/sdk.md#exemplar-defaults
 	// Explicit bucket histogram aggregation with more than 1 bucket will
 	// use AlignedHistogramBucketExemplarReservoir.
 	a, ok := agg.(AggregationExplicitBucketHistogram)
 	if ok && len(a.Boundaries) > 0 {
-		cp := slices.Clone(a.Boundaries)
-		return func() exemplar.FilteredReservoir[N] {
-			bounds := cp
-			return exemplar.NewFilteredReservoir[N](filter, exemplar.Histogram(bounds))
-		}
+		return exemplar.HistogramReservoirProvider(a.Boundaries)
 	}
 
 	var n int
@@ -75,7 +73,5 @@ func reservoirFunc[N int64 | float64](agg Aggregation) func() exemplar.FilteredR
 		}
 	}
 
-	return func() exemplar.FilteredReservoir[N] {
-		return exemplar.NewFilteredReservoir[N](filter, exemplar.FixedSize(n))
-	}
+	return exemplar.FixedSizeReservoirProvider(n)
 }

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/README.md

@@ -0,0 +1,3 @@
+# Metric SDK Exemplars
+
+[![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel/sdk/metric/exemplar)](https://pkg.go.dev/go.opentelemetry.io/otel/sdk/metric/exemplar)

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/doc.go

@@ -3,4 +3,4 @@
 
 // Package exemplar provides an implementation of the OpenTelemetry exemplar
 // reservoir to be used in metric collection pipelines.
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/exemplar.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import (
 	"time"

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/filter.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import (
 	"context"
@@ -16,10 +16,10 @@ import (
 // Reservoir in making a sampling decision.
 type Filter func(context.Context) bool
 
-// SampledFilter is a [Filter] that will only offer measurements
+// TraceBasedFilter is a [Filter] that will only offer measurements
 // if the passed context associated with the measurement contains a sampled
 // [go.opentelemetry.io/otel/trace.SpanContext].
-func SampledFilter(ctx context.Context) bool {
+func TraceBasedFilter(ctx context.Context) bool {
 	return trace.SpanContextFromContext(ctx).IsSampled()
 }
 
@@ -27,3 +27,8 @@ func SampledFilter(ctx context.Context) bool {
 func AlwaysOnFilter(ctx context.Context) bool {
 	return true
 }
+
+// AlwaysOffFilter is a [Filter] that never offers measurements.
+func AlwaysOffFilter(ctx context.Context) bool {
+	return false
+}

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/fixed_size_reservoir.go

@@ -1,31 +1,69 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import (
 	"context"
 	"math"
 	"math/rand"
-	"sync"
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
 )
 
-var (
+// FixedSizeReservoirProvider returns a provider of [FixedSizeReservoir].
+func FixedSizeReservoirProvider(k int) ReservoirProvider {
+	return func(_ attribute.Set) Reservoir {
+		return NewFixedSizeReservoir(k)
+	}
+}
+
+// NewFixedSizeReservoir returns a [FixedSizeReservoir] that samples at most
+// k exemplars. If there are k or less measurements made, the Reservoir will
+// sample each one. If there are more than k, the Reservoir will then randomly
+// sample all additional measurement with a decreasing probability.
+func NewFixedSizeReservoir(k int) *FixedSizeReservoir {
+	return newFixedSizeReservoir(newStorage(k))
+}
+
+var _ Reservoir = &FixedSizeReservoir{}
+
+// FixedSizeReservoir is a [Reservoir] that samples at most k exemplars. If
+// there are k or less measurements made, the Reservoir will sample each one.
+// If there are more than k, the Reservoir will then randomly sample all
+// additional measurement with a decreasing probability.
+type FixedSizeReservoir struct {
+	*storage
+
+	// count is the number of measurement seen.
+	count int64
+	// next is the next count that will store a measurement at a random index
+	// once the reservoir has been filled.
+	next int64
+	// w is the largest random number in a distribution that is used to compute
+	// the next next.
+	w float64
+
 	// rng is used to make sampling decisions.
 	//
 	// Do not use crypto/rand. There is no reason for the decrease in performance
 	// given this is not a security sensitive decision.
-	rng = rand.New(rand.NewSource(time.Now().UnixNano()))
-	// Ensure concurrent safe accecess to rng and its underlying source.
-	rngMu sync.Mutex
-)
+	rng *rand.Rand
+}
 
-// random returns, as a float64, a uniform pseudo-random number in the open
-// interval (0.0,1.0).
-func random() float64 {
+func newFixedSizeReservoir(s *storage) *FixedSizeReservoir {
+	r := &FixedSizeReservoir{
+		storage: s,
+		rng:     rand.New(rand.NewSource(time.Now().UnixNano())),
+	}
+	r.reset()
+	return r
+}
+
+// randomFloat64 returns, as a float64, a uniform pseudo-random number in the
+// open interval (0.0,1.0).
+func (r *FixedSizeReservoir) randomFloat64() float64 {
 	// TODO: This does not return a uniform number. rng.Float64 returns a
 	// uniformly random int in [0,2^53) that is divided by 2^53. Meaning it
 	// returns multiples of 2^-53, and not all floating point numbers between 0
@@ -43,40 +81,25 @@ func random() float64 {
 	//
 	// There are likely many other methods to explore here as well.
 
-	rngMu.Lock()
-	defer rngMu.Unlock()
-
-	f := rng.Float64()
+	f := r.rng.Float64()
 	for f == 0 {
-		f = rng.Float64()
+		f = r.rng.Float64()
 	}
 	return f
 }
 
-// FixedSize returns a [Reservoir] that samples at most k exemplars. If there
-// are k or less measurements made, the Reservoir will sample each one. If
-// there are more than k, the Reservoir will then randomly sample all
-// additional measurement with a decreasing probability.
-func FixedSize(k int) Reservoir {
-	r := &randRes{storage: newStorage(k)}
-	r.reset()
-	return r
-}
-
-type randRes struct {
-	*storage
-
-	// count is the number of measurement seen.
-	count int64
-	// next is the next count that will store a measurement at a random index
-	// once the reservoir has been filled.
-	next int64
-	// w is the largest random number in a distribution that is used to compute
-	// the next next.
-	w float64
-}
-
-func (r *randRes) Offer(ctx context.Context, t time.Time, n Value, a []attribute.KeyValue) {
+// Offer accepts the parameters associated with a measurement. The
+// parameters will be stored as an exemplar if the Reservoir decides to
+// sample the measurement.
+//
+// The passed ctx needs to contain any baggage or span that were active
+// when the measurement was made. This information may be used by the
+// Reservoir in making a sampling decision.
+//
+// The time t is the time when the measurement was made. The v and a
+// parameters are the value and dropped (filtered) attributes of the
+// measurement respectively.
+func (r *FixedSizeReservoir) Offer(ctx context.Context, t time.Time, n Value, a []attribute.KeyValue) {
 	// The following algorithm is "Algorithm L" from Li, Kim-Hung (4 December
 	// 1994). "Reservoir-Sampling Algorithms of Time Complexity
 	// O(n(1+log(N/n)))". ACM Transactions on Mathematical Software. 20 (4):
@@ -123,7 +146,7 @@ func (r *randRes) Offer(ctx context.Context, t time.Time, n Value, a []attribute
 	} else {
 		if r.count == r.next {
 			// Overwrite a random existing measurement with the one offered.
-			idx := int(rng.Int63n(int64(cap(r.store))))
+			idx := int(r.rng.Int63n(int64(cap(r.store))))
 			r.store[idx] = newMeasurement(ctx, t, n, a)
 			r.advance()
 		}
@@ -132,7 +155,7 @@ func (r *randRes) Offer(ctx context.Context, t time.Time, n Value, a []attribute
 }
 
 // reset resets r to the initial state.
-func (r *randRes) reset() {
+func (r *FixedSizeReservoir) reset() {
 	// This resets the number of exemplars known.
 	r.count = 0
 	// Random index inserts should only happen after the storage is full.
@@ -147,14 +170,14 @@ func (r *randRes) reset() {
 	// This maps the uniform random number in (0,1) to a geometric distribution
 	// over the same interval. The mean of the distribution is inversely
 	// proportional to the storage capacity.
-	r.w = math.Exp(math.Log(random()) / float64(cap(r.store)))
+	r.w = math.Exp(math.Log(r.randomFloat64()) / float64(cap(r.store)))
 
 	r.advance()
 }
 
 // advance updates the count at which the offered measurement will overwrite an
 // existing exemplar.
-func (r *randRes) advance() {
+func (r *FixedSizeReservoir) advance() {
 	// Calculate the next value in the random number series.
 	//
 	// The current value of r.w is based on the max of a distribution of random
@@ -167,7 +190,7 @@ func (r *randRes) advance() {
 	// therefore the next r.w will be based on the same distribution (i.e.
 	// `max(u_1,u_2,...,u_k)`). Therefore, we can sample the next r.w by
 	// computing the next random number `u` and take r.w as `w * u^(1/k)`.
-	r.w *= math.Exp(math.Log(random()) / float64(cap(r.store)))
+	r.w *= math.Exp(math.Log(r.randomFloat64()) / float64(cap(r.store)))
 	// Use the new random number in the series to calculate the count of the
 	// next measurement that will be stored.
 	//
@@ -178,10 +201,13 @@ func (r *randRes) advance() {
 	//
 	// Important to note, the new r.next will always be at least 1 more than
 	// the last r.next.
-	r.next += int64(math.Log(random())/math.Log(1-r.w)) + 1
+	r.next += int64(math.Log(r.randomFloat64())/math.Log(1-r.w)) + 1
 }
 
-func (r *randRes) Collect(dest *[]Exemplar) {
+// Collect returns all the held exemplars.
+//
+// The Reservoir state is preserved after this call.
+func (r *FixedSizeReservoir) Collect(dest *[]Exemplar) {
 	r.storage.Collect(dest)
 	// Call reset here even though it will reset r.count and restart the random
 	// number series. This will persist any old exemplars as long as no new

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/histogram_reservoir.go

@@ -0,0 +1,70 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
+
+import (
+	"context"
+	"slices"
+	"sort"
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// HistogramReservoirProvider is a provider of [HistogramReservoir].
+func HistogramReservoirProvider(bounds []float64) ReservoirProvider {
+	cp := slices.Clone(bounds)
+	slices.Sort(cp)
+	return func(_ attribute.Set) Reservoir {
+		return NewHistogramReservoir(cp)
+	}
+}
+
+// NewHistogramReservoir returns a [HistogramReservoir] that samples the last
+// measurement that falls within a histogram bucket. The histogram bucket
+// upper-boundaries are define by bounds.
+//
+// The passed bounds must be sorted before calling this function.
+func NewHistogramReservoir(bounds []float64) *HistogramReservoir {
+	return &HistogramReservoir{
+		bounds:  bounds,
+		storage: newStorage(len(bounds) + 1),
+	}
+}
+
+var _ Reservoir = &HistogramReservoir{}
+
+// HistogramReservoir is a [Reservoir] that samples the last measurement that
+// falls within a histogram bucket. The histogram bucket upper-boundaries are
+// define by bounds.
+type HistogramReservoir struct {
+	*storage
+
+	// bounds are bucket bounds in ascending order.
+	bounds []float64
+}
+
+// Offer accepts the parameters associated with a measurement. The
+// parameters will be stored as an exemplar if the Reservoir decides to
+// sample the measurement.
+//
+// The passed ctx needs to contain any baggage or span that were active
+// when the measurement was made. This information may be used by the
+// Reservoir in making a sampling decision.
+//
+// The time t is the time when the measurement was made. The v and a
+// parameters are the value and dropped (filtered) attributes of the
+// measurement respectively.
+func (r *HistogramReservoir) Offer(ctx context.Context, t time.Time, v Value, a []attribute.KeyValue) {
+	var x float64
+	switch v.Type() {
+	case Int64ValueType:
+		x = float64(v.Int64())
+	case Float64ValueType:
+		x = v.Float64()
+	default:
+		panic("unknown value type")
+	}
+	r.store[sort.SearchFloat64s(r.bounds, x)] = newMeasurement(ctx, t, v, a)
+}

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/reservoir.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import (
 	"context"
@@ -30,3 +30,11 @@ type Reservoir interface {
 	// The Reservoir state is preserved after this call.
 	Collect(dest *[]Exemplar)
 }
+
+// ReservoirProvider creates new [Reservoir]s.
+//
+// The attributes provided are attributes which are kept by the aggregation, and
+// are exclusive with attributes passed to Offer. The combination of these
+// attributes and the attributes passed to Offer is the complete set of
+// attributes a measurement was made with.
+type ReservoirProvider func(attr attribute.Set) Reservoir

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/storage.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import (
 	"context"
@@ -35,7 +35,7 @@ func (r *storage) Collect(dest *[]Exemplar) {
 			continue
 		}
 
-		m.Exemplar(&(*dest)[n])
+		m.exemplar(&(*dest)[n])
 		n++
 	}
 	*dest = (*dest)[:n]
@@ -66,8 +66,8 @@ func newMeasurement(ctx context.Context, ts time.Time, v Value, droppedAttr []at
 	}
 }
 
-// Exemplar returns m as an [Exemplar].
-func (m measurement) Exemplar(dest *Exemplar) {
+// exemplar returns m as an [Exemplar].
+func (m measurement) exemplar(dest *Exemplar) {
 	dest.FilteredAttributes = m.FilteredAttributes
 	dest.Time = m.Time
 	dest.Value = m.Value

vendor/go.opentelemetry.io/otel/sdk/metric/exemplar/value.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+package exemplar // import "go.opentelemetry.io/otel/sdk/metric/exemplar"
 
 import "math"
 
@@ -28,7 +28,8 @@ type Value struct {
 func NewValue[N int64 | float64](value N) Value {
 	switch v := any(value).(type) {
 	case int64:
-		return Value{t: Int64ValueType, val: uint64(v)}
+		// This can be later converted back to int64 (overflow not checked).
+		return Value{t: Int64ValueType, val: uint64(v)} // nolint:gosec
 	case float64:
 		return Value{t: Float64ValueType, val: math.Float64bits(v)}
 	}

vendor/go.opentelemetry.io/otel/sdk/metric/exporter.go

@@ -5,14 +5,14 @@ package metric // import "go.opentelemetry.io/otel/sdk/metric"
 
 import (
 	"context"
-	"fmt"
+	"errors"
 
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
 // ErrExporterShutdown is returned if Export or Shutdown are called after an
 // Exporter has been Shutdown.
-var ErrExporterShutdown = fmt.Errorf("exporter is shutdown")
+var ErrExporterShutdown = errors.New("exporter is shutdown")
 
 // Exporter handles the delivery of metric data to external receivers. This is
 // the final component in the metric push pipeline.

vendor/go.opentelemetry.io/otel/sdk/metric/instrument.go

@@ -16,6 +16,7 @@ import (
 	"go.opentelemetry.io/otel/metric/embedded"
 	"go.opentelemetry.io/otel/sdk/instrumentation"
 	"go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
+	"go.opentelemetry.io/otel/sdk/metric/internal/x"
 )
 
 var zeroScope instrumentation.Scope
@@ -144,6 +145,12 @@ type Stream struct {
 	// Use NewAllowKeysFilter from "go.opentelemetry.io/otel/attribute" to
 	// provide an allow-list of attribute keys here.
 	AttributeFilter attribute.Filter
+	// ExemplarReservoirProvider selects the
+	// [go.opentelemetry.io/otel/sdk/metric/exemplar.ReservoirProvider] based
+	// on the [Aggregation].
+	//
+	// If unspecified, [DefaultExemplarReservoirProviderSelector] is used.
+	ExemplarReservoirProviderSelector ExemplarReservoirProviderSelector
 }
 
 // instID are the identifying properties of a instrument.
@@ -184,6 +191,7 @@ var (
 	_ metric.Int64UpDownCounter = (*int64Inst)(nil)
 	_ metric.Int64Histogram     = (*int64Inst)(nil)
 	_ metric.Int64Gauge         = (*int64Inst)(nil)
+	_ x.EnabledInstrument       = (*int64Inst)(nil)
 )
 
 func (i *int64Inst) Add(ctx context.Context, val int64, opts ...metric.AddOption) {
@@ -196,6 +204,10 @@ func (i *int64Inst) Record(ctx context.Context, val int64, opts ...metric.Record
 	i.aggregate(ctx, val, c.Attributes())
 }
 
+func (i *int64Inst) Enabled(_ context.Context) bool {
+	return len(i.measures) != 0
+}
+
 func (i *int64Inst) aggregate(ctx context.Context, val int64, s attribute.Set) { // nolint:revive  // okay to shadow pkg with method.
 	for _, in := range i.measures {
 		in(ctx, val, s)
@@ -216,6 +228,7 @@ var (
 	_ metric.Float64UpDownCounter = (*float64Inst)(nil)
 	_ metric.Float64Histogram     = (*float64Inst)(nil)
 	_ metric.Float64Gauge         = (*float64Inst)(nil)
+	_ x.EnabledInstrument         = (*float64Inst)(nil)
 )
 
 func (i *float64Inst) Add(ctx context.Context, val float64, opts ...metric.AddOption) {
@@ -228,14 +241,18 @@ func (i *float64Inst) Record(ctx context.Context, val float64, opts ...metric.Re
 	i.aggregate(ctx, val, c.Attributes())
 }
 
+func (i *float64Inst) Enabled(_ context.Context) bool {
+	return len(i.measures) != 0
+}
+
 func (i *float64Inst) aggregate(ctx context.Context, val float64, s attribute.Set) {
 	for _, in := range i.measures {
 		in(ctx, val, s)
 	}
 }
 
-// observablID is a comparable unique identifier of an observable.
-type observablID[N int64 | float64] struct {
+// observableID is a comparable unique identifier of an observable.
+type observableID[N int64 | float64] struct {
 	name        string
 	description string
 	kind        InstrumentKind
@@ -287,7 +304,7 @@ func newInt64Observable(m *meter, kind InstrumentKind, name, desc, u string) int
 
 type observable[N int64 | float64] struct {
 	metric.Observable
-	observablID[N]
+	observableID[N]
 
 	meter           *meter
 	measures        measures[N]
@@ -296,7 +313,7 @@ type observable[N int64 | float64] struct {
 
 func newObservable[N int64 | float64](m *meter, kind InstrumentKind, name, desc, u string) *observable[N] {
 	return &observable[N]{
-		observablID: observablID[N]{
+		observableID: observableID[N]{
 			name:        name,
 			description: desc,
 			kind:        kind,

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/aggregate.go

@@ -8,7 +8,6 @@ import (
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
@@ -38,8 +37,8 @@ type Builder[N int64 | float64] struct {
 	// create new exemplar reservoirs for a new seen attribute set.
 	//
 	// If this is not provided a default factory function that returns an
-	// exemplar.Drop reservoir will be used.
-	ReservoirFunc func() exemplar.FilteredReservoir[N]
+	// dropReservoir reservoir will be used.
+	ReservoirFunc func(attribute.Set) FilteredExemplarReservoir[N]
 	// AggregationLimit is the cardinality limit of measurement attributes. Any
 	// measurement for new attributes once the limit has been reached will be
 	// aggregated into a single aggregate for the "otel.metric.overflow"
@@ -50,12 +49,12 @@ type Builder[N int64 | float64] struct {
 	AggregationLimit int
 }
 
-func (b Builder[N]) resFunc() func() exemplar.FilteredReservoir[N] {
+func (b Builder[N]) resFunc() func(attribute.Set) FilteredExemplarReservoir[N] {
 	if b.ReservoirFunc != nil {
 		return b.ReservoirFunc
 	}
 
-	return exemplar.Drop
+	return dropReservoir
 }
 
 type fltrMeasure[N int64 | float64] func(ctx context.Context, value N, fltrAttr attribute.Set, droppedAttr []attribute.KeyValue)

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/drop.go

@@ -0,0 +1,27 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package aggregate // import "go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
+)
+
+// dropReservoir returns a [FilteredReservoir] that drops all measurements it is offered.
+func dropReservoir[N int64 | float64](attribute.Set) FilteredExemplarReservoir[N] {
+	return &dropRes[N]{}
+}
+
+type dropRes[N int64 | float64] struct{}
+
+// Offer does nothing, all measurements offered will be dropped.
+func (r *dropRes[N]) Offer(context.Context, N, []attribute.KeyValue) {}
+
+// Collect resets dest. No exemplars will ever be returned.
+func (r *dropRes[N]) Collect(dest *[]exemplar.Exemplar) {
+	clear(*dest) // Erase elements to let GC collect objects
+	*dest = (*dest)[:0]
+}

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/exemplar.go

@@ -6,7 +6,7 @@ package aggregate // import "go.opentelemetry.io/otel/sdk/metric/internal/aggreg
 import (
 	"sync"
 
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
@@ -17,6 +17,7 @@ var exemplarPool = sync.Pool{
 func collectExemplars[N int64 | float64](out *[]metricdata.Exemplar[N], f func(*[]exemplar.Exemplar)) {
 	dest := exemplarPool.Get().(*[]exemplar.Exemplar)
 	defer func() {
+		clear(*dest) // Erase elements to let GC collect objects.
 		*dest = (*dest)[:0]
 		exemplarPool.Put(dest)
 	}()

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/exponential_histogram.go

@@ -12,7 +12,6 @@ import (
 
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
@@ -31,7 +30,7 @@ const (
 // expoHistogramDataPoint is a single data point in an exponential histogram.
 type expoHistogramDataPoint[N int64 | float64] struct {
 	attrs attribute.Set
-	res   exemplar.FilteredReservoir[N]
+	res   FilteredExemplarReservoir[N]
 
 	count uint64
 	min   N
@@ -51,16 +50,16 @@ type expoHistogramDataPoint[N int64 | float64] struct {
 
 func newExpoHistogramDataPoint[N int64 | float64](attrs attribute.Set, maxSize int, maxScale int32, noMinMax, noSum bool) *expoHistogramDataPoint[N] {
 	f := math.MaxFloat64
-	max := N(f) // if N is int64, max will overflow to -9223372036854775808
-	min := N(-f)
+	ma := N(f) // if N is int64, max will overflow to -9223372036854775808
+	mi := N(-f)
 	if N(maxInt64) > N(f) {
-		max = N(maxInt64)
-		min = N(minInt64)
+		ma = N(maxInt64)
+		mi = N(minInt64)
 	}
 	return &expoHistogramDataPoint[N]{
 		attrs:    attrs,
-		min:      max,
-		max:      min,
+		min:      ma,
+		max:      mi,
 		maxSize:  maxSize,
 		noMinMax: noMinMax,
 		noSum:    noSum,
@@ -284,7 +283,7 @@ func (b *expoBuckets) downscale(delta int32) {
 // newExponentialHistogram returns an Aggregator that summarizes a set of
 // measurements as an exponential histogram. Each histogram is scoped by attributes
 // and the aggregation cycle the measurements were made in.
-func newExponentialHistogram[N int64 | float64](maxSize, maxScale int32, noMinMax, noSum bool, limit int, r func() exemplar.FilteredReservoir[N]) *expoHistogram[N] {
+func newExponentialHistogram[N int64 | float64](maxSize, maxScale int32, noMinMax, noSum bool, limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *expoHistogram[N] {
 	return &expoHistogram[N]{
 		noSum:    noSum,
 		noMinMax: noMinMax,
@@ -307,7 +306,7 @@ type expoHistogram[N int64 | float64] struct {
 	maxSize  int
 	maxScale int32
 
-	newRes   func() exemplar.FilteredReservoir[N]
+	newRes   func(attribute.Set) FilteredExemplarReservoir[N]
 	limit    limiter[*expoHistogramDataPoint[N]]
 	values   map[attribute.Distinct]*expoHistogramDataPoint[N]
 	valuesMu sync.Mutex
@@ -328,7 +327,7 @@ func (e *expoHistogram[N]) measure(ctx context.Context, value N, fltrAttr attrib
 	v, ok := e.values[attr.Equivalent()]
 	if !ok {
 		v = newExpoHistogramDataPoint[N](attr, e.maxSize, e.maxScale, e.noMinMax, e.noSum)
-		v.res = e.newRes()
+		v.res = e.newRes(attr)
 
 		e.values[attr.Equivalent()] = v
 	}

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/filtered_reservoir.go

@@ -0,0 +1,50 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package aggregate // import "go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
+
+import (
+	"context"
+	"time"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
+)
+
+// FilteredExemplarReservoir wraps a [exemplar.Reservoir] with a filter.
+type FilteredExemplarReservoir[N int64 | float64] interface {
+	// Offer accepts the parameters associated with a measurement. The
+	// parameters will be stored as an exemplar if the filter decides to
+	// sample the measurement.
+	//
+	// The passed ctx needs to contain any baggage or span that were active
+	// when the measurement was made. This information may be used by the
+	// Reservoir in making a sampling decision.
+	Offer(ctx context.Context, val N, attr []attribute.KeyValue)
+	// Collect returns all the held exemplars in the reservoir.
+	Collect(dest *[]exemplar.Exemplar)
+}
+
+// filteredExemplarReservoir handles the pre-sampled exemplar of measurements made.
+type filteredExemplarReservoir[N int64 | float64] struct {
+	filter    exemplar.Filter
+	reservoir exemplar.Reservoir
+}
+
+// NewFilteredExemplarReservoir creates a [FilteredExemplarReservoir] which only offers values
+// that are allowed by the filter.
+func NewFilteredExemplarReservoir[N int64 | float64](f exemplar.Filter, r exemplar.Reservoir) FilteredExemplarReservoir[N] {
+	return &filteredExemplarReservoir[N]{
+		filter:    f,
+		reservoir: r,
+	}
+}
+
+func (f *filteredExemplarReservoir[N]) Offer(ctx context.Context, val N, attr []attribute.KeyValue) {
+	if f.filter(ctx) {
+		// only record the current time if we are sampling this measurement.
+		f.reservoir.Offer(ctx, time.Now(), exemplar.NewValue(val), attr)
+	}
+}
+
+func (f *filteredExemplarReservoir[N]) Collect(dest *[]exemplar.Exemplar) { f.reservoir.Collect(dest) }

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/histogram.go

@@ -11,13 +11,12 @@ import (
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
 type buckets[N int64 | float64] struct {
 	attrs attribute.Set
-	res   exemplar.FilteredReservoir[N]
+	res   FilteredExemplarReservoir[N]
 
 	counts   []uint64
 	count    uint64
@@ -48,13 +47,13 @@ type histValues[N int64 | float64] struct {
 	noSum  bool
 	bounds []float64
 
-	newRes   func() exemplar.FilteredReservoir[N]
+	newRes   func(attribute.Set) FilteredExemplarReservoir[N]
 	limit    limiter[*buckets[N]]
 	values   map[attribute.Distinct]*buckets[N]
 	valuesMu sync.Mutex
 }
 
-func newHistValues[N int64 | float64](bounds []float64, noSum bool, limit int, r func() exemplar.FilteredReservoir[N]) *histValues[N] {
+func newHistValues[N int64 | float64](bounds []float64, noSum bool, limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *histValues[N] {
 	// The responsibility of keeping all buckets correctly associated with the
 	// passed boundaries is ultimately this type's responsibility. Make a copy
 	// here so we can always guarantee this. Or, in the case of failure, have
@@ -94,7 +93,7 @@ func (s *histValues[N]) measure(ctx context.Context, value N, fltrAttr attribute
 		//
 		//   buckets = (-∞, 0], (0, 5.0], (5.0, 10.0], (10.0, +∞)
 		b = newBuckets[N](attr, len(s.bounds)+1)
-		b.res = s.newRes()
+		b.res = s.newRes(attr)
 
 		// Ensure min and max are recorded values (not zero), for new buckets.
 		b.min, b.max = value, value
@@ -109,7 +108,7 @@ func (s *histValues[N]) measure(ctx context.Context, value N, fltrAttr attribute
 
 // newHistogram returns an Aggregator that summarizes a set of measurements as
 // an histogram.
-func newHistogram[N int64 | float64](boundaries []float64, noMinMax, noSum bool, limit int, r func() exemplar.FilteredReservoir[N]) *histogram[N] {
+func newHistogram[N int64 | float64](boundaries []float64, noMinMax, noSum bool, limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *histogram[N] {
 	return &histogram[N]{
 		histValues: newHistValues[N](boundaries, noSum, limit, r),
 		noMinMax:   noMinMax,

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/lastvalue.go

@@ -9,7 +9,6 @@ import (
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
@@ -17,10 +16,10 @@ import (
 type datapoint[N int64 | float64] struct {
 	attrs attribute.Set
 	value N
-	res   exemplar.FilteredReservoir[N]
+	res   FilteredExemplarReservoir[N]
 }
 
-func newLastValue[N int64 | float64](limit int, r func() exemplar.FilteredReservoir[N]) *lastValue[N] {
+func newLastValue[N int64 | float64](limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *lastValue[N] {
 	return &lastValue[N]{
 		newRes: r,
 		limit:  newLimiter[datapoint[N]](limit),
@@ -33,7 +32,7 @@ func newLastValue[N int64 | float64](limit int, r func() exemplar.FilteredReserv
 type lastValue[N int64 | float64] struct {
 	sync.Mutex
 
-	newRes func() exemplar.FilteredReservoir[N]
+	newRes func(attribute.Set) FilteredExemplarReservoir[N]
 	limit  limiter[datapoint[N]]
 	values map[attribute.Distinct]datapoint[N]
 	start  time.Time
@@ -46,7 +45,7 @@ func (s *lastValue[N]) measure(ctx context.Context, value N, fltrAttr attribute.
 	attr := s.limit.Attributes(fltrAttr, s.values)
 	d, ok := s.values[attr.Equivalent()]
 	if !ok {
-		d.res = s.newRes()
+		d.res = s.newRes(attr)
 	}
 
 	d.attrs = attr
@@ -115,7 +114,7 @@ func (s *lastValue[N]) copyDpts(dest *[]metricdata.DataPoint[N], t time.Time) in
 
 // newPrecomputedLastValue returns an aggregator that summarizes a set of
 // observations as the last one made.
-func newPrecomputedLastValue[N int64 | float64](limit int, r func() exemplar.FilteredReservoir[N]) *precomputedLastValue[N] {
+func newPrecomputedLastValue[N int64 | float64](limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *precomputedLastValue[N] {
 	return &precomputedLastValue[N]{lastValue: newLastValue[N](limit, r)}
 }
 

vendor/go.opentelemetry.io/otel/sdk/metric/internal/aggregate/sum.go

@@ -9,25 +9,24 @@ import (
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
-	"go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
 type sumValue[N int64 | float64] struct {
 	n     N
-	res   exemplar.FilteredReservoir[N]
+	res   FilteredExemplarReservoir[N]
 	attrs attribute.Set
 }
 
 // valueMap is the storage for sums.
 type valueMap[N int64 | float64] struct {
 	sync.Mutex
-	newRes func() exemplar.FilteredReservoir[N]
+	newRes func(attribute.Set) FilteredExemplarReservoir[N]
 	limit  limiter[sumValue[N]]
 	values map[attribute.Distinct]sumValue[N]
 }
 
-func newValueMap[N int64 | float64](limit int, r func() exemplar.FilteredReservoir[N]) *valueMap[N] {
+func newValueMap[N int64 | float64](limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *valueMap[N] {
 	return &valueMap[N]{
 		newRes: r,
 		limit:  newLimiter[sumValue[N]](limit),
@@ -42,7 +41,7 @@ func (s *valueMap[N]) measure(ctx context.Context, value N, fltrAttr attribute.S
 	attr := s.limit.Attributes(fltrAttr, s.values)
 	v, ok := s.values[attr.Equivalent()]
 	if !ok {
-		v.res = s.newRes()
+		v.res = s.newRes(attr)
 	}
 
 	v.attrs = attr
@@ -55,7 +54,7 @@ func (s *valueMap[N]) measure(ctx context.Context, value N, fltrAttr attribute.S
 // newSum returns an aggregator that summarizes a set of measurements as their
 // arithmetic sum. Each sum is scoped by attributes and the aggregation cycle
 // the measurements were made in.
-func newSum[N int64 | float64](monotonic bool, limit int, r func() exemplar.FilteredReservoir[N]) *sum[N] {
+func newSum[N int64 | float64](monotonic bool, limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *sum[N] {
 	return &sum[N]{
 		valueMap:  newValueMap[N](limit, r),
 		monotonic: monotonic,
@@ -142,9 +141,9 @@ func (s *sum[N]) cumulative(dest *metricdata.Aggregation) int {
 }
 
 // newPrecomputedSum returns an aggregator that summarizes a set of
-// observatrions as their arithmetic sum. Each sum is scoped by attributes and
+// observations as their arithmetic sum. Each sum is scoped by attributes and
 // the aggregation cycle the measurements were made in.
-func newPrecomputedSum[N int64 | float64](monotonic bool, limit int, r func() exemplar.FilteredReservoir[N]) *precomputedSum[N] {
+func newPrecomputedSum[N int64 | float64](monotonic bool, limit int, r func(attribute.Set) FilteredExemplarReservoir[N]) *precomputedSum[N] {
 	return &precomputedSum[N]{
 		valueMap:  newValueMap[N](limit, r),
 		monotonic: monotonic,
@@ -152,7 +151,7 @@ func newPrecomputedSum[N int64 | float64](monotonic bool, limit int, r func() ex
 	}
 }
 
-// precomputedSum summarizes a set of observatrions as their arithmetic sum.
+// precomputedSum summarizes a set of observations as their arithmetic sum.
 type precomputedSum[N int64 | float64] struct {
 	*valueMap[N]
 

vendor/go.opentelemetry.io/otel/sdk/metric/internal/exemplar/drop.go

@@ -1,23 +0,0 @@
-// Copyright The OpenTelemetry Authors
-// SPDX-License-Identifier: Apache-2.0
-
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
-
-import (
-	"context"
-
-	"go.opentelemetry.io/otel/attribute"
-)
-
-// Drop returns a [FilteredReservoir] that drops all measurements it is offered.
-func Drop[N int64 | float64]() FilteredReservoir[N] { return &dropRes[N]{} }
-
-type dropRes[N int64 | float64] struct{}
-
-// Offer does nothing, all measurements offered will be dropped.
-func (r *dropRes[N]) Offer(context.Context, N, []attribute.KeyValue) {}
-
-// Collect resets dest. No exemplars will ever be returned.
-func (r *dropRes[N]) Collect(dest *[]Exemplar) {
-	*dest = (*dest)[:0]
-}

vendor/go.opentelemetry.io/otel/sdk/metric/internal/exemplar/filtered_reservoir.go

@@ -1,49 +0,0 @@
-// Copyright The OpenTelemetry Authors
-// SPDX-License-Identifier: Apache-2.0
-
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
-
-import (
-	"context"
-	"time"
-
-	"go.opentelemetry.io/otel/attribute"
-)
-
-// FilteredReservoir wraps a [Reservoir] with a filter.
-type FilteredReservoir[N int64 | float64] interface {
-	// Offer accepts the parameters associated with a measurement. The
-	// parameters will be stored as an exemplar if the filter decides to
-	// sample the measurement.
-	//
-	// The passed ctx needs to contain any baggage or span that were active
-	// when the measurement was made. This information may be used by the
-	// Reservoir in making a sampling decision.
-	Offer(ctx context.Context, val N, attr []attribute.KeyValue)
-	// Collect returns all the held exemplars in the reservoir.
-	Collect(dest *[]Exemplar)
-}
-
-// filteredReservoir handles the pre-sampled exemplar of measurements made.
-type filteredReservoir[N int64 | float64] struct {
-	filter    Filter
-	reservoir Reservoir
-}
-
-// NewFilteredReservoir creates a [FilteredReservoir] which only offers values
-// that are allowed by the filter.
-func NewFilteredReservoir[N int64 | float64](f Filter, r Reservoir) FilteredReservoir[N] {
-	return &filteredReservoir[N]{
-		filter:    f,
-		reservoir: r,
-	}
-}
-
-func (f *filteredReservoir[N]) Offer(ctx context.Context, val N, attr []attribute.KeyValue) {
-	if f.filter(ctx) {
-		// only record the current time if we are sampling this measurment.
-		f.reservoir.Offer(ctx, time.Now(), NewValue(val), attr)
-	}
-}
-
-func (f *filteredReservoir[N]) Collect(dest *[]Exemplar) { f.reservoir.Collect(dest) }

vendor/go.opentelemetry.io/otel/sdk/metric/internal/exemplar/hist.go

@@ -1,46 +0,0 @@
-// Copyright The OpenTelemetry Authors
-// SPDX-License-Identifier: Apache-2.0
-
-package exemplar // import "go.opentelemetry.io/otel/sdk/metric/internal/exemplar"
-
-import (
-	"context"
-	"slices"
-	"sort"
-	"time"
-
-	"go.opentelemetry.io/otel/attribute"
-)
-
-// Histogram returns a [Reservoir] that samples the last measurement that falls
-// within a histogram bucket. The histogram bucket upper-boundaries are define
-// by bounds.
-//
-// The passed bounds will be sorted by this function.
-func Histogram(bounds []float64) Reservoir {
-	slices.Sort(bounds)
-	return &histRes{
-		bounds:  bounds,
-		storage: newStorage(len(bounds) + 1),
-	}
-}
-
-type histRes struct {
-	*storage
-
-	// bounds are bucket bounds in ascending order.
-	bounds []float64
-}
-
-func (r *histRes) Offer(ctx context.Context, t time.Time, v Value, a []attribute.KeyValue) {
-	var x float64
-	switch v.Type() {
-	case Int64ValueType:
-		x = float64(v.Int64())
-	case Float64ValueType:
-		x = v.Float64()
-	default:
-		panic("unknown value type")
-	}
-	r.store[sort.SearchFloat64s(r.bounds, x)] = newMeasurement(ctx, t, v, a)
-}

vendor/go.opentelemetry.io/otel/sdk/metric/internal/x/README.md

@@ -10,6 +10,7 @@ See the [Compatibility and Stability](#compatibility-and-stability) section for
 
 - [Cardinality Limit](#cardinality-limit)
 - [Exemplars](#exemplars)
+- [Instrument Enabled](#instrument-enabled)
 
 ### Cardinality Limit
 
@@ -102,6 +103,24 @@ Revert to the default exemplar filter (`"trace_based"`)
 unset OTEL_METRICS_EXEMPLAR_FILTER
 ```
 
+### Instrument Enabled
+
+To help users avoid performing computationally expensive operations when recording measurements, synchronous instruments provide an `Enabled` method.
+
+#### Examples
+
+The following code shows an example of how to check if an instrument implements the `EnabledInstrument` interface before using the `Enabled` function to avoid doing an expensive computation:
+
+```go
+type enabledInstrument interface { Enabled(context.Context) bool }
+
+ctr, err := m.Int64Counter("expensive-counter")
+c, ok := ctr.(enabledInstrument)
+if !ok || c.Enabled(context.Background()) {
+    c.Add(expensiveComputation())
+}
+```
+
 ## Compatibility and Stability
 
 Experimental features do not fall within the scope of the OpenTelemetry Go versioning and stability [policy](../../../../VERSIONING.md).

vendor/go.opentelemetry.io/otel/sdk/metric/internal/x/x.go

@@ -8,41 +8,26 @@
 package x // import "go.opentelemetry.io/otel/sdk/metric/internal/x"
 
 import (
+	"context"
 	"os"
 	"strconv"
-	"strings"
 )
 
-var (
-	// Exemplars is an experimental feature flag that defines if exemplars
-	// should be recorded for metric data-points.
-	//
-	// To enable this feature set the OTEL_GO_X_EXEMPLAR environment variable
-	// to the case-insensitive string value of "true" (i.e. "True" and "TRUE"
-	// will also enable this).
-	Exemplars = newFeature("EXEMPLAR", func(v string) (string, bool) {
-		if strings.ToLower(v) == "true" {
-			return v, true
-		}
-		return "", false
-	})
-
-	// CardinalityLimit is an experimental feature flag that defines if
-	// cardinality limits should be applied to the recorded metric data-points.
-	//
-	// To enable this feature set the OTEL_GO_X_CARDINALITY_LIMIT environment
-	// variable to the integer limit value you want to use.
-	//
-	// Setting OTEL_GO_X_CARDINALITY_LIMIT to a value less than or equal to 0
-	// will disable the cardinality limits.
-	CardinalityLimit = newFeature("CARDINALITY_LIMIT", func(v string) (int, bool) {
-		n, err := strconv.Atoi(v)
-		if err != nil {
-			return 0, false
-		}
-		return n, true
-	})
-)
+// CardinalityLimit is an experimental feature flag that defines if
+// cardinality limits should be applied to the recorded metric data-points.
+//
+// To enable this feature set the OTEL_GO_X_CARDINALITY_LIMIT environment
+// variable to the integer limit value you want to use.
+//
+// Setting OTEL_GO_X_CARDINALITY_LIMIT to a value less than or equal to 0
+// will disable the cardinality limits.
+var CardinalityLimit = newFeature("CARDINALITY_LIMIT", func(v string) (int, bool) {
+	n, err := strconv.Atoi(v)
+	if err != nil {
+		return 0, false
+	}
+	return n, true
+})
 
 // Feature is an experimental feature control flag. It provides a uniform way
 // to interact with these feature flags and parse their values.
@@ -83,3 +68,14 @@ func (f Feature[T]) Enabled() bool {
 	_, ok := f.Lookup()
 	return ok
 }
+
+// EnabledInstrument informs whether the instrument is enabled.
+//
+// EnabledInstrument interface is implemented by synchronous instruments.
+type EnabledInstrument interface {
+	// Enabled returns whether the instrument will process measurements for the given context.
+	//
+	// This function can be used in places where measuring an instrument
+	// would result in computationally expensive operations.
+	Enabled(context.Context) bool
+}

vendor/go.opentelemetry.io/otel/sdk/metric/manual_reader.go

@@ -113,18 +113,17 @@ func (mr *ManualReader) Collect(ctx context.Context, rm *metricdata.ResourceMetr
 	if err != nil {
 		return err
 	}
-	var errs []error
 	for _, producer := range mr.externalProducers.Load().([]Producer) {
-		externalMetrics, err := producer.Produce(ctx)
-		if err != nil {
-			errs = append(errs, err)
+		externalMetrics, e := producer.Produce(ctx)
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		rm.ScopeMetrics = append(rm.ScopeMetrics, externalMetrics...)
 	}
 
 	global.Debug("ManualReader collection", "Data", rm)
 
-	return unifyErrors(errs)
+	return err
 }
 
 // MarshalLog returns logging data about the ManualReader.

vendor/go.opentelemetry.io/otel/sdk/metric/meter.go

@@ -150,6 +150,11 @@ func (m *meter) int64ObservableInstrument(id Instrument, callbacks []metric.Int6
 				continue
 			}
 			inst.appendMeasures(in)
+
+			// Add the measures to the pipeline. It is required to maintain
+			// measures per pipeline to avoid calling the measure that
+			// is not part of the pipeline.
+			insert.pipeline.addInt64Measure(inst.observableID, in)
 			for _, cback := range callbacks {
 				inst := int64Observer{measures: in}
 				fn := cback
@@ -309,6 +314,11 @@ func (m *meter) float64ObservableInstrument(id Instrument, callbacks []metric.Fl
 				continue
 			}
 			inst.appendMeasures(in)
+
+			// Add the measures to the pipeline. It is required to maintain
+			// measures per pipeline to avoid calling the measure that
+			// is not part of the pipeline.
+			insert.pipeline.addFloat64Measure(inst.observableID, in)
 			for _, cback := range callbacks {
 				inst := float64Observer{measures: in}
 				fn := cback
@@ -441,73 +451,80 @@ func (m *meter) RegisterCallback(f metric.Callback, insts ...metric.Observable)
 		return noopRegister{}, nil
 	}
 
-	reg := newObserver()
-	var errs multierror
+	var err error
+	validInstruments := make([]metric.Observable, 0, len(insts))
 	for _, inst := range insts {
-		// Unwrap any global.
-		if u, ok := inst.(interface {
-			Unwrap() metric.Observable
-		}); ok {
-			inst = u.Unwrap()
-		}
-
 		switch o := inst.(type) {
 		case int64Observable:
-			if err := o.registerable(m); err != nil {
-				if !errors.Is(err, errEmptyAgg) {
-					errs.append(err)
+			if e := o.registerable(m); e != nil {
+				if !errors.Is(e, errEmptyAgg) {
+					err = errors.Join(err, e)
 				}
 				continue
 			}
-			reg.registerInt64(o.observablID)
+
+			validInstruments = append(validInstruments, inst)
 		case float64Observable:
-			if err := o.registerable(m); err != nil {
-				if !errors.Is(err, errEmptyAgg) {
-					errs.append(err)
+			if e := o.registerable(m); e != nil {
+				if !errors.Is(e, errEmptyAgg) {
+					err = errors.Join(err, e)
 				}
 				continue
 			}
-			reg.registerFloat64(o.observablID)
+
+			validInstruments = append(validInstruments, inst)
 		default:
 			// Instrument external to the SDK.
-			return nil, fmt.Errorf("invalid observable: from different implementation")
+			return nil, errors.New("invalid observable: from different implementation")
 		}
 	}
 
-	err := errs.errorOrNil()
-	if reg.len() == 0 {
+	if len(validInstruments) == 0 {
 		// All insts use drop aggregation or are invalid.
 		return noopRegister{}, err
 	}
 
-	// Some or all instruments were valid.
-	cback := func(ctx context.Context) error { return f(ctx, reg) }
-	return m.pipes.registerMultiCallback(cback), err
+	unregs := make([]func(), len(m.pipes))
+	for ix, pipe := range m.pipes {
+		reg := newObserver(pipe)
+		for _, inst := range validInstruments {
+			switch o := inst.(type) {
+			case int64Observable:
+				reg.registerInt64(o.observableID)
+			case float64Observable:
+				reg.registerFloat64(o.observableID)
+			}
+		}
+
+		// Some or all instruments were valid.
+		cBack := func(ctx context.Context) error { return f(ctx, reg) }
+		unregs[ix] = pipe.addMultiCallback(cBack)
+	}
+
+	return unregisterFuncs{f: unregs}, err
 }
 
 type observer struct {
 	embedded.Observer
 
-	float64 map[observablID[float64]]struct{}
-	int64   map[observablID[int64]]struct{}
+	pipe    *pipeline
+	float64 map[observableID[float64]]struct{}
+	int64   map[observableID[int64]]struct{}
 }
 
-func newObserver() observer {
+func newObserver(p *pipeline) observer {
 	return observer{
-		float64: make(map[observablID[float64]]struct{}),
-		int64:   make(map[observablID[int64]]struct{}),
+		pipe:    p,
+		float64: make(map[observableID[float64]]struct{}),
+		int64:   make(map[observableID[int64]]struct{}),
 	}
 }
 
-func (r observer) len() int {
-	return len(r.float64) + len(r.int64)
-}
-
-func (r observer) registerFloat64(id observablID[float64]) {
+func (r observer) registerFloat64(id observableID[float64]) {
 	r.float64[id] = struct{}{}
 }
 
-func (r observer) registerInt64(id observablID[int64]) {
+func (r observer) registerInt64(id observableID[int64]) {
 	r.int64[id] = struct{}{}
 }
 
@@ -521,22 +538,12 @@ func (r observer) ObserveFloat64(o metric.Float64Observable, v float64, opts ...
 	switch conv := o.(type) {
 	case float64Observable:
 		oImpl = conv
-	case interface {
-		Unwrap() metric.Observable
-	}:
-		// Unwrap any global.
-		async := conv.Unwrap()
-		var ok bool
-		if oImpl, ok = async.(float64Observable); !ok {
-			global.Error(errUnknownObserver, "failed to record asynchronous")
-			return
-		}
 	default:
 		global.Error(errUnknownObserver, "failed to record")
 		return
 	}
 
-	if _, registered := r.float64[oImpl.observablID]; !registered {
+	if _, registered := r.float64[oImpl.observableID]; !registered {
 		if !oImpl.dropAggregation {
 			global.Error(errUnregObserver, "failed to record",
 				"name", oImpl.name,
@@ -548,7 +555,12 @@ func (r observer) ObserveFloat64(o metric.Float64Observable, v float64, opts ...
 		return
 	}
 	c := metric.NewObserveConfig(opts)
-	oImpl.observe(v, c.Attributes())
+	// Access to r.pipe.float64Measure is already guarded by a lock in pipeline.produce.
+	// TODO (#5946): Refactor pipeline and observable measures.
+	measures := r.pipe.float64Measures[oImpl.observableID]
+	for _, m := range measures {
+		m(context.Background(), v, c.Attributes())
+	}
 }
 
 func (r observer) ObserveInt64(o metric.Int64Observable, v int64, opts ...metric.ObserveOption) {
@@ -556,22 +568,12 @@ func (r observer) ObserveInt64(o metric.Int64Observable, v int64, opts ...metric
 	switch conv := o.(type) {
 	case int64Observable:
 		oImpl = conv
-	case interface {
-		Unwrap() metric.Observable
-	}:
-		// Unwrap any global.
-		async := conv.Unwrap()
-		var ok bool
-		if oImpl, ok = async.(int64Observable); !ok {
-			global.Error(errUnknownObserver, "failed to record asynchronous")
-			return
-		}
 	default:
 		global.Error(errUnknownObserver, "failed to record")
 		return
 	}
 
-	if _, registered := r.int64[oImpl.observablID]; !registered {
+	if _, registered := r.int64[oImpl.observableID]; !registered {
 		if !oImpl.dropAggregation {
 			global.Error(errUnregObserver, "failed to record",
 				"name", oImpl.name,
@@ -583,7 +585,12 @@ func (r observer) ObserveInt64(o metric.Int64Observable, v int64, opts ...metric
 		return
 	}
 	c := metric.NewObserveConfig(opts)
-	oImpl.observe(v, c.Attributes())
+	// Access to r.pipe.int64Measures is already guarded b a lock in pipeline.produce.
+	// TODO (#5946): Refactor pipeline and observable measures.
+	measures := r.pipe.int64Measures[oImpl.observableID]
+	for _, m := range measures {
+		m(context.Background(), v, c.Attributes())
+	}
 }
 
 type noopRegister struct{ embedded.Registration }

vendor/go.opentelemetry.io/otel/sdk/metric/periodic_reader.go

@@ -251,18 +251,17 @@ func (r *PeriodicReader) collect(ctx context.Context, p interface{}, rm *metricd
 	if err != nil {
 		return err
 	}
-	var errs []error
 	for _, producer := range r.externalProducers.Load().([]Producer) {
-		externalMetrics, err := producer.Produce(ctx)
-		if err != nil {
-			errs = append(errs, err)
+		externalMetrics, e := producer.Produce(ctx)
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		rm.ScopeMetrics = append(rm.ScopeMetrics, externalMetrics...)
 	}
 
 	global.Debug("PeriodicReader collection", "Data", rm)
 
-	return unifyErrors(errs)
+	return err
 }
 
 // export exports metric data m using r's exporter.

vendor/go.opentelemetry.io/otel/sdk/metric/pipeline.go

@@ -8,14 +8,13 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"strings"
 	"sync"
 	"sync/atomic"
 
 	"go.opentelemetry.io/otel/internal/global"
-	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/metric/embedded"
 	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/sdk/metric/exemplar"
 	"go.opentelemetry.io/otel/sdk/metric/internal"
 	"go.opentelemetry.io/otel/sdk/metric/internal/aggregate"
 	"go.opentelemetry.io/otel/sdk/metric/internal/x"
@@ -38,14 +37,17 @@ type instrumentSync struct {
 	compAgg     aggregate.ComputeAggregation
 }
 
-func newPipeline(res *resource.Resource, reader Reader, views []View) *pipeline {
+func newPipeline(res *resource.Resource, reader Reader, views []View, exemplarFilter exemplar.Filter) *pipeline {
 	if res == nil {
 		res = resource.Empty()
 	}
 	return &pipeline{
-		resource: res,
-		reader:   reader,
-		views:    views,
+		resource:        res,
+		reader:          reader,
+		views:           views,
+		int64Measures:   map[observableID[int64]][]aggregate.Measure[int64]{},
+		float64Measures: map[observableID[float64]][]aggregate.Measure[float64]{},
+		exemplarFilter:  exemplarFilter,
 		// aggregations is lazy allocated when needed.
 	}
 }
@@ -63,9 +65,26 @@ type pipeline struct {
 	views  []View
 
 	sync.Mutex
-	aggregations   map[instrumentation.Scope][]instrumentSync
-	callbacks      []func(context.Context) error
-	multiCallbacks list.List
+	int64Measures   map[observableID[int64]][]aggregate.Measure[int64]
+	float64Measures map[observableID[float64]][]aggregate.Measure[float64]
+	aggregations    map[instrumentation.Scope][]instrumentSync
+	callbacks       []func(context.Context) error
+	multiCallbacks  list.List
+	exemplarFilter  exemplar.Filter
+}
+
+// addInt64Measure adds a new int64 measure to the pipeline for each observer.
+func (p *pipeline) addInt64Measure(id observableID[int64], m []aggregate.Measure[int64]) {
+	p.Lock()
+	defer p.Unlock()
+	p.int64Measures[id] = m
+}
+
+// addFloat64Measure adds a new float64 measure to the pipeline for each observer.
+func (p *pipeline) addFloat64Measure(id observableID[float64], m []aggregate.Measure[float64]) {
+	p.Lock()
+	defer p.Unlock()
+	p.float64Measures[id] = m
 }
 
 // addSync adds the instrumentSync to pipeline p with scope. This method is not
@@ -105,14 +124,15 @@ func (p *pipeline) produce(ctx context.Context, rm *metricdata.ResourceMetrics)
 	p.Lock()
 	defer p.Unlock()
 
-	var errs multierror
+	var err error
 	for _, c := range p.callbacks {
 		// TODO make the callbacks parallel. ( #3034 )
-		if err := c(ctx); err != nil {
-			errs.append(err)
+		if e := c(ctx); e != nil {
+			err = errors.Join(err, e)
 		}
 		if err := ctx.Err(); err != nil {
 			rm.Resource = nil
+			clear(rm.ScopeMetrics) // Erase elements to let GC collect objects.
 			rm.ScopeMetrics = rm.ScopeMetrics[:0]
 			return err
 		}
@@ -120,12 +140,13 @@ func (p *pipeline) produce(ctx context.Context, rm *metricdata.ResourceMetrics)
 	for e := p.multiCallbacks.Front(); e != nil; e = e.Next() {
 		// TODO make the callbacks parallel. ( #3034 )
 		f := e.Value.(multiCallback)
-		if err := f(ctx); err != nil {
-			errs.append(err)
+		if e := f(ctx); e != nil {
+			err = errors.Join(err, e)
 		}
 		if err := ctx.Err(); err != nil {
 			// This means the context expired before we finished running callbacks.
 			rm.Resource = nil
+			clear(rm.ScopeMetrics) // Erase elements to let GC collect objects.
 			rm.ScopeMetrics = rm.ScopeMetrics[:0]
 			return err
 		}
@@ -157,7 +178,7 @@ func (p *pipeline) produce(ctx context.Context, rm *metricdata.ResourceMetrics)
 
 	rm.ScopeMetrics = rm.ScopeMetrics[:i]
 
-	return errs.errorOrNil()
+	return err
 }
 
 // inserter facilitates inserting of new instruments from a single scope into a
@@ -219,7 +240,7 @@ func (i *inserter[N]) Instrument(inst Instrument, readerAggregation Aggregation)
 		measures []aggregate.Measure[N]
 	)
 
-	errs := &multierror{wrapped: errCreatingAggregators}
+	var err error
 	seen := make(map[uint64]struct{})
 	for _, v := range i.pipeline.views {
 		stream, match := v(inst)
@@ -227,9 +248,9 @@ func (i *inserter[N]) Instrument(inst Instrument, readerAggregation Aggregation)
 			continue
 		}
 		matched = true
-		in, id, err := i.cachedAggregator(inst.Scope, inst.Kind, stream, readerAggregation)
-		if err != nil {
-			errs.append(err)
+		in, id, e := i.cachedAggregator(inst.Scope, inst.Kind, stream, readerAggregation)
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		if in == nil { // Drop aggregation.
 			continue
@@ -242,8 +263,12 @@ func (i *inserter[N]) Instrument(inst Instrument, readerAggregation Aggregation)
 		measures = append(measures, in)
 	}
 
+	if err != nil {
+		err = errors.Join(errCreatingAggregators, err)
+	}
+
 	if matched {
-		return measures, errs.errorOrNil()
+		return measures, err
 	}
 
 	// Apply implicit default view if no explicit matched.
@@ -252,15 +277,18 @@ func (i *inserter[N]) Instrument(inst Instrument, readerAggregation Aggregation)
 		Description: inst.Description,
 		Unit:        inst.Unit,
 	}
-	in, _, err := i.cachedAggregator(inst.Scope, inst.Kind, stream, readerAggregation)
-	if err != nil {
-		errs.append(err)
+	in, _, e := i.cachedAggregator(inst.Scope, inst.Kind, stream, readerAggregation)
+	if e != nil {
+		if err == nil {
+			err = errCreatingAggregators
+		}
+		err = errors.Join(err, e)
 	}
 	if in != nil {
 		// Ensured to have not seen given matched was false.
 		measures = append(measures, in)
 	}
-	return measures, errs.errorOrNil()
+	return measures, err
 }
 
 // addCallback registers a single instrument callback to be run when
@@ -329,6 +357,9 @@ func (i *inserter[N]) cachedAggregator(scope instrumentation.Scope, kind Instrum
 		// The view explicitly requested the default aggregation.
 		stream.Aggregation = DefaultAggregationSelector(kind)
 	}
+	if stream.ExemplarReservoirProviderSelector == nil {
+		stream.ExemplarReservoirProviderSelector = DefaultExemplarReservoirProviderSelector
+	}
 
 	if err := isAggregatorCompatible(kind, stream.Aggregation); err != nil {
 		return nil, 0, fmt.Errorf(
@@ -349,7 +380,7 @@ func (i *inserter[N]) cachedAggregator(scope instrumentation.Scope, kind Instrum
 	cv := i.aggregators.Lookup(normID, func() aggVal[N] {
 		b := aggregate.Builder[N]{
 			Temporality:   i.pipeline.reader.temporality(kind),
-			ReservoirFunc: reservoirFunc[N](stream.Aggregation),
+			ReservoirFunc: reservoirFunc[N](stream.ExemplarReservoirProviderSelector(stream.Aggregation), i.pipeline.exemplarFilter),
 		}
 		b.Filter = stream.AttributeFilter
 		// A value less than or equal to zero will disable the aggregation
@@ -552,24 +583,16 @@ func isAggregatorCompatible(kind InstrumentKind, agg Aggregation) error {
 // measurement.
 type pipelines []*pipeline
 
-func newPipelines(res *resource.Resource, readers []Reader, views []View) pipelines {
+func newPipelines(res *resource.Resource, readers []Reader, views []View, exemplarFilter exemplar.Filter) pipelines {
 	pipes := make([]*pipeline, 0, len(readers))
 	for _, r := range readers {
-		p := newPipeline(res, r, views)
+		p := newPipeline(res, r, views, exemplarFilter)
 		r.register(p)
 		pipes = append(pipes, p)
 	}
 	return pipes
 }
 
-func (p pipelines) registerMultiCallback(c multiCallback) metric.Registration {
-	unregs := make([]func(), len(p))
-	for i, pipe := range p {
-		unregs[i] = pipe.addMultiCallback(c)
-	}
-	return unregisterFuncs{f: unregs}
-}
-
 type unregisterFuncs struct {
 	embedded.Registration
 	f []func()
@@ -602,15 +625,15 @@ func newResolver[N int64 | float64](p pipelines, vc *cache[string, instID]) reso
 func (r resolver[N]) Aggregators(id Instrument) ([]aggregate.Measure[N], error) {
 	var measures []aggregate.Measure[N]
 
-	errs := &multierror{}
+	var err error
 	for _, i := range r.inserters {
-		in, err := i.Instrument(id, i.readerDefaultAggregation(id.Kind))
-		if err != nil {
-			errs.append(err)
+		in, e := i.Instrument(id, i.readerDefaultAggregation(id.Kind))
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		measures = append(measures, in...)
 	}
-	return measures, errs.errorOrNil()
+	return measures, err
 }
 
 // HistogramAggregators returns the histogram Aggregators that must be updated by the instrument
@@ -619,37 +642,18 @@ func (r resolver[N]) Aggregators(id Instrument) ([]aggregate.Measure[N], error)
 func (r resolver[N]) HistogramAggregators(id Instrument, boundaries []float64) ([]aggregate.Measure[N], error) {
 	var measures []aggregate.Measure[N]
 
-	errs := &multierror{}
+	var err error
 	for _, i := range r.inserters {
 		agg := i.readerDefaultAggregation(id.Kind)
 		if histAgg, ok := agg.(AggregationExplicitBucketHistogram); ok && len(boundaries) > 0 {
 			histAgg.Boundaries = boundaries
 			agg = histAgg
 		}
-		in, err := i.Instrument(id, agg)
-		if err != nil {
-			errs.append(err)
+		in, e := i.Instrument(id, agg)
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		measures = append(measures, in...)
 	}
-	return measures, errs.errorOrNil()
-}
-
-type multierror struct {
-	wrapped error
-	errors  []string
-}
-
-func (m *multierror) errorOrNil() error {
-	if len(m.errors) == 0 {
-		return nil
-	}
-	if m.wrapped == nil {
-		return errors.New(strings.Join(m.errors, "; "))
-	}
-	return fmt.Errorf("%w: %s", m.wrapped, strings.Join(m.errors, "; "))
-}
-
-func (m *multierror) append(err error) {
-	m.errors = append(m.errors, err.Error())
+	return measures, err
 }

vendor/go.opentelemetry.io/otel/sdk/metric/provider.go

@@ -42,7 +42,7 @@ func NewMeterProvider(options ...Option) *MeterProvider {
 	flush, sdown := conf.readerSignals()
 
 	mp := &MeterProvider{
-		pipes:      newPipelines(conf.res, conf.readers, conf.views),
+		pipes:      newPipelines(conf.res, conf.readers, conf.views, conf.exemplarFilter),
 		forceFlush: flush,
 		shutdown:   sdown,
 	}
@@ -76,15 +76,17 @@ func (mp *MeterProvider) Meter(name string, options ...metric.MeterOption) metri
 
 	c := metric.NewMeterConfig(options...)
 	s := instrumentation.Scope{
-		Name:      name,
-		Version:   c.InstrumentationVersion(),
-		SchemaURL: c.SchemaURL(),
+		Name:       name,
+		Version:    c.InstrumentationVersion(),
+		SchemaURL:  c.SchemaURL(),
+		Attributes: c.InstrumentationAttributes(),
 	}
 
 	global.Info("Meter created",
 		"Name", s.Name,
 		"Version", s.Version,
 		"SchemaURL", s.SchemaURL,
+		"Attributes", s.Attributes,
 	)
 
 	return mp.meters.Lookup(s, func() *meter {

vendor/go.opentelemetry.io/otel/sdk/metric/reader.go

@@ -5,26 +5,26 @@ package metric // import "go.opentelemetry.io/otel/sdk/metric"
 
 import (
 	"context"
-	"fmt"
+	"errors"
 
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 )
 
 // errDuplicateRegister is logged by a Reader when an attempt to registered it
 // more than once occurs.
-var errDuplicateRegister = fmt.Errorf("duplicate reader registration")
+var errDuplicateRegister = errors.New("duplicate reader registration")
 
 // ErrReaderNotRegistered is returned if Collect or Shutdown are called before
 // the reader is registered with a MeterProvider.
-var ErrReaderNotRegistered = fmt.Errorf("reader is not registered")
+var ErrReaderNotRegistered = errors.New("reader is not registered")
 
 // ErrReaderShutdown is returned if Collect or Shutdown are called after a
 // reader has been Shutdown once.
-var ErrReaderShutdown = fmt.Errorf("reader is shutdown")
+var ErrReaderShutdown = errors.New("reader is shutdown")
 
 // errNonPositiveDuration is logged when an environmental variable
 // has non-positive value.
-var errNonPositiveDuration = fmt.Errorf("non-positive duration")
+var errNonPositiveDuration = errors.New("non-positive duration")
 
 // Reader is the interface used between the SDK and an
 // exporter.  Control flow is bi-directional through the
@@ -60,8 +60,8 @@ type Reader interface {
 	aggregation(InstrumentKind) Aggregation // nolint:revive  // import-shadow for method scoped by type.
 
 	// Collect gathers and returns all metric data related to the Reader from
-	// the SDK and stores it in out. An error is returned if this is called
-	// after Shutdown or if out is nil.
+	// the SDK and stores it in rm. An error is returned if this is called
+	// after Shutdown or if rm is nil.
 	//
 	// This method needs to be concurrent safe, and the cancellation of the
 	// passed context is expected to be honored.

vendor/go.opentelemetry.io/otel/sdk/metric/version.go

@@ -5,5 +5,5 @@ package metric // import "go.opentelemetry.io/otel/sdk/metric"
 
 // version is the current release version of the metric SDK in use.
 func version() string {
-	return "1.29.0"
+	return "1.34.0"
 }

vendor/go.opentelemetry.io/otel/sdk/metric/view.go

@@ -96,11 +96,12 @@ func NewView(criteria Instrument, mask Stream) View {
 	return func(i Instrument) (Stream, bool) {
 		if matchFunc(i) {
 			return Stream{
-				Name:            nonZero(mask.Name, i.Name),
-				Description:     nonZero(mask.Description, i.Description),
-				Unit:            nonZero(mask.Unit, i.Unit),
-				Aggregation:     agg,
-				AttributeFilter: mask.AttributeFilter,
+				Name:                              nonZero(mask.Name, i.Name),
+				Description:                       nonZero(mask.Description, i.Description),
+				Unit:                              nonZero(mask.Unit, i.Unit),
+				Aggregation:                       agg,
+				AttributeFilter:                   mask.AttributeFilter,
+				ExemplarReservoirProviderSelector: mask.ExemplarReservoirProviderSelector,
 			}, true
 		}
 		return Stream{}, false

vendor/go.opentelemetry.io/otel/sdk/resource/auto.go

@@ -7,7 +7,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"strings"
 )
 
 // ErrPartialResource is returned by a detector when complete source
@@ -57,62 +56,37 @@ func Detect(ctx context.Context, detectors ...Detector) (*Resource, error) {
 // these errors will be returned. Otherwise, nil is returned.
 func detect(ctx context.Context, res *Resource, detectors []Detector) error {
 	var (
-		r    *Resource
-		errs detectErrs
-		err  error
+		r   *Resource
+		err error
+		e   error
 	)
 
 	for _, detector := range detectors {
 		if detector == nil {
 			continue
 		}
-		r, err = detector.Detect(ctx)
-		if err != nil {
-			errs = append(errs, err)
-			if !errors.Is(err, ErrPartialResource) {
+		r, e = detector.Detect(ctx)
+		if e != nil {
+			err = errors.Join(err, e)
+			if !errors.Is(e, ErrPartialResource) {
 				continue
 			}
 		}
-		r, err = Merge(res, r)
-		if err != nil {
-			errs = append(errs, err)
+		r, e = Merge(res, r)
+		if e != nil {
+			err = errors.Join(err, e)
 		}
 		*res = *r
 	}
 
-	if len(errs) == 0 {
-		return nil
+	if err != nil {
+		if errors.Is(err, ErrSchemaURLConflict) {
+			// If there has been a merge conflict, ensure the resource has no
+			// schema URL.
+			res.schemaURL = ""
+		}
+
+		err = fmt.Errorf("error detecting resource: %w", err)
 	}
-	if errors.Is(errs, ErrSchemaURLConflict) {
-		// If there has been a merge conflict, ensure the resource has no
-		// schema URL.
-		res.schemaURL = ""
-	}
-	return errs
-}
-
-type detectErrs []error
-
-func (e detectErrs) Error() string {
-	errStr := make([]string, len(e))
-	for i, err := range e {
-		errStr[i] = fmt.Sprintf("* %s", err)
-	}
-
-	format := "%d errors occurred detecting resource:\n\t%s"
-	return fmt.Sprintf(format, len(e), strings.Join(errStr, "\n\t"))
-}
-
-func (e detectErrs) Unwrap() error {
-	switch len(e) {
-	case 0:
-		return nil
-	case 1:
-		return e[0]
-	}
-	return e[1:]
-}
-
-func (e detectErrs) Is(target error) bool {
-	return len(e) != 0 && errors.Is(e[0], target)
+	return err
 }

vendor/go.opentelemetry.io/otel/sdk/resource/builtin.go

@@ -20,15 +20,13 @@ type (
 	// telemetrySDK is a Detector that provides information about
 	// the OpenTelemetry SDK used.  This Detector is included as a
 	// builtin. If these resource attributes are not wanted, use
-	// the WithTelemetrySDK(nil) or WithoutBuiltin() options to
-	// explicitly disable them.
+	// resource.New() to explicitly disable them.
 	telemetrySDK struct{}
 
 	// host is a Detector that provides information about the host
 	// being run on. This Detector is included as a builtin. If
 	// these resource attributes are not wanted, use the
-	// WithHost(nil) or WithoutBuiltin() options to explicitly
-	// disable them.
+	// resource.New() to explicitly disable them.
 	host struct{}
 
 	stringDetector struct {

vendor/go.opentelemetry.io/otel/sdk/resource/host_id_windows.go

@@ -10,17 +10,16 @@ import (
 	"golang.org/x/sys/windows/registry"
 )
 
-// implements hostIDReader
+// implements hostIDReader.
 type hostIDReaderWindows struct{}
 
-// read reads MachineGuid from the windows registry key:
-// SOFTWARE\Microsoft\Cryptography
+// read reads MachineGuid from the Windows registry key:
+// SOFTWARE\Microsoft\Cryptography.
 func (*hostIDReaderWindows) read() (string, error) {
 	k, err := registry.OpenKey(
 		registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Cryptography`,
 		registry.QUERY_VALUE|registry.WOW64_64KEY,
 	)
-
 	if err != nil {
 		return "", err
 	}

vendor/go.opentelemetry.io/otel/sdk/resource/os_windows.go

@@ -17,7 +17,6 @@ import (
 func platformOSDescription() (string, error) {
 	k, err := registry.OpenKey(
 		registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Windows NT\CurrentVersion`, registry.QUERY_VALUE)
-
 	if err != nil {
 		return "", err
 	}

vendor/go.opentelemetry.io/otel/sdk/trace/batch_span_processor.go

@@ -280,6 +280,7 @@ func (bsp *batchSpanProcessor) exportSpans(ctx context.Context) error {
 		//
 		// It is up to the exporter to implement any type of retry logic if a batch is failing
 		// to be exported, since it is specific to the protocol and backend being sent to.
+		clear(bsp.batch) // Erase elements to let GC collect objects
 		bsp.batch = bsp.batch[:0]
 
 		if err != nil {
@@ -316,7 +317,11 @@ func (bsp *batchSpanProcessor) processQueue() {
 			bsp.batchMutex.Unlock()
 			if shouldExport {
 				if !bsp.timer.Stop() {
-					<-bsp.timer.C
+					// Handle both GODEBUG=asynctimerchan=[0|1] properly.
+					select {
+					case <-bsp.timer.C:
+					default:
+					}
 				}
 				if err := bsp.exportSpans(ctx); err != nil {
 					otel.Handle(err)

vendor/go.opentelemetry.io/otel/sdk/trace/evictedqueue.go

@@ -12,25 +12,26 @@ import (
 
 // evictedQueue is a FIFO queue with a configurable capacity.
 type evictedQueue[T any] struct {
-	queue        []T
-	capacity     int
-	droppedCount int
-	logDropped   func()
+	queue          []T
+	capacity       int
+	droppedCount   int
+	logDroppedMsg  string
+	logDroppedOnce sync.Once
 }
 
 func newEvictedQueueEvent(capacity int) evictedQueue[Event] {
 	// Do not pre-allocate queue, do this lazily.
 	return evictedQueue[Event]{
-		capacity:   capacity,
-		logDropped: sync.OnceFunc(func() { global.Warn("limit reached: dropping trace trace.Event") }),
+		capacity:      capacity,
+		logDroppedMsg: "limit reached: dropping trace trace.Event",
 	}
 }
 
 func newEvictedQueueLink(capacity int) evictedQueue[Link] {
 	// Do not pre-allocate queue, do this lazily.
 	return evictedQueue[Link]{
-		capacity:   capacity,
-		logDropped: sync.OnceFunc(func() { global.Warn("limit reached: dropping trace trace.Link") }),
+		capacity:      capacity,
+		logDroppedMsg: "limit reached: dropping trace trace.Link",
 	}
 }
 
@@ -53,6 +54,10 @@ func (eq *evictedQueue[T]) add(value T) {
 	eq.queue = append(eq.queue, value)
 }
 
+func (eq *evictedQueue[T]) logDropped() {
+	eq.logDroppedOnce.Do(func() { global.Warn(eq.logDroppedMsg) })
+}
+
 // copy returns a copy of the evictedQueue.
 func (eq *evictedQueue[T]) copy() []T {
 	return slices.Clone(eq.queue)

vendor/go.opentelemetry.io/otel/sdk/trace/provider.go

@@ -139,9 +139,10 @@ func (p *TracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.T
 		name = defaultTracerName
 	}
 	is := instrumentation.Scope{
-		Name:      name,
-		Version:   c.InstrumentationVersion(),
-		SchemaURL: c.SchemaURL(),
+		Name:       name,
+		Version:    c.InstrumentationVersion(),
+		SchemaURL:  c.SchemaURL(),
+		Attributes: c.InstrumentationAttributes(),
 	}
 
 	t, ok := func() (trace.Tracer, bool) {
@@ -168,7 +169,7 @@ func (p *TracerProvider) Tracer(name string, opts ...trace.TracerOption) trace.T
 		//   slowing down all tracing consumers.
 		// - Logging code may be instrumented with tracing and deadlock because it could try
 		//   acquiring the same non-reentrant mutex.
-		global.Info("Tracer created", "name", name, "version", is.Version, "schemaURL", is.SchemaURL)
+		global.Info("Tracer created", "name", name, "version", is.Version, "schemaURL", is.SchemaURL, "attributes", is.Attributes)
 	}
 	return t
 }

vendor/go.opentelemetry.io/otel/sdk/trace/sampler_env.go

@@ -5,7 +5,6 @@ package trace // import "go.opentelemetry.io/otel/sdk/trace"
 
 import (
 	"errors"
-	"fmt"
 	"os"
 	"strconv"
 	"strings"
@@ -26,7 +25,7 @@ const (
 type errUnsupportedSampler string
 
 func (e errUnsupportedSampler) Error() string {
-	return fmt.Sprintf("unsupported sampler: %s", string(e))
+	return "unsupported sampler: " + string(e)
 }
 
 var (
@@ -39,7 +38,7 @@ type samplerArgParseError struct {
 }
 
 func (e samplerArgParseError) Error() string {
-	return fmt.Sprintf("parsing sampler argument: %s", e.parseErr.Error())
+	return "parsing sampler argument: " + e.parseErr.Error()
 }
 
 func (e samplerArgParseError) Unwrap() error {

vendor/go.opentelemetry.io/otel/sdk/trace/span.go

@@ -174,6 +174,17 @@ func (s *recordingSpan) IsRecording() bool {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
+	return s.isRecording()
+}
+
+// isRecording returns if this span is being recorded. If this span has ended
+// this will return false.
+//
+// This method assumes s.mu.Lock is held by the caller.
+func (s *recordingSpan) isRecording() bool {
+	if s == nil {
+		return false
+	}
 	return s.endTime.IsZero()
 }
 
@@ -182,11 +193,15 @@ func (s *recordingSpan) IsRecording() bool {
 // included in the set status when the code is for an error. If this span is
 // not being recorded than this method does nothing.
 func (s *recordingSpan) SetStatus(code codes.Code, description string) {
-	if !s.IsRecording() {
+	if s == nil {
 		return
 	}
+
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	if !s.isRecording() {
+		return
+	}
 	if s.status.Code > code {
 		return
 	}
@@ -210,12 +225,15 @@ func (s *recordingSpan) SetStatus(code codes.Code, description string) {
 // attributes the span is configured to have, the last added attributes will
 // be dropped.
 func (s *recordingSpan) SetAttributes(attributes ...attribute.KeyValue) {
-	if !s.IsRecording() {
+	if s == nil || len(attributes) == 0 {
 		return
 	}
 
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	if !s.isRecording() {
+		return
+	}
 
 	limit := s.tracer.provider.spanLimits.AttributeCountLimit
 	if limit == 0 {
@@ -233,7 +251,7 @@ func (s *recordingSpan) SetAttributes(attributes ...attribute.KeyValue) {
 
 	// Otherwise, add without deduplication. When attributes are read they
 	// will be deduplicated, optimizing the operation.
-	s.attributes = slices.Grow(s.attributes, len(s.attributes)+len(attributes))
+	s.attributes = slices.Grow(s.attributes, len(attributes))
 	for _, a := range attributes {
 		if !a.Valid() {
 			// Drop all invalid attributes.
@@ -280,13 +298,17 @@ func (s *recordingSpan) addOverCapAttrs(limit int, attrs []attribute.KeyValue) {
 
 	// Do not set a capacity when creating this map. Benchmark testing has
 	// showed this to only add unused memory allocations in general use.
-	exists := make(map[attribute.Key]int)
-	s.dedupeAttrsFromRecord(&exists)
+	exists := make(map[attribute.Key]int, len(s.attributes))
+	s.dedupeAttrsFromRecord(exists)
 
 	// Now that s.attributes is deduplicated, adding unique attributes up to
 	// the capacity of s will not over allocate s.attributes.
-	sum := len(attrs) + len(s.attributes)
-	s.attributes = slices.Grow(s.attributes, min(sum, limit))
+
+	// max size = limit
+	maxCap := min(len(attrs)+len(s.attributes), limit)
+	if cap(s.attributes) < maxCap {
+		s.attributes = slices.Grow(s.attributes, maxCap-cap(s.attributes))
+	}
 	for _, a := range attrs {
 		if !a.Valid() {
 			// Drop all invalid attributes.
@@ -296,6 +318,7 @@ func (s *recordingSpan) addOverCapAttrs(limit int, attrs []attribute.KeyValue) {
 
 		if idx, ok := exists[a.Key]; ok {
 			// Perform all updates before dropping, even when at capacity.
+			a = truncateAttr(s.tracer.provider.spanLimits.AttributeValueLengthLimit, a)
 			s.attributes[idx] = a
 			continue
 		}
@@ -324,54 +347,99 @@ func truncateAttr(limit int, attr attribute.KeyValue) attribute.KeyValue {
 	}
 	switch attr.Value.Type() {
 	case attribute.STRING:
-		if v := attr.Value.AsString(); len(v) > limit {
-			return attr.Key.String(safeTruncate(v, limit))
-		}
+		v := attr.Value.AsString()
+		return attr.Key.String(truncate(limit, v))
 	case attribute.STRINGSLICE:
 		v := attr.Value.AsStringSlice()
 		for i := range v {
-			if len(v[i]) > limit {
-				v[i] = safeTruncate(v[i], limit)
-			}
+			v[i] = truncate(limit, v[i])
 		}
 		return attr.Key.StringSlice(v)
 	}
 	return attr
 }
 
-// safeTruncate truncates the string and guarantees valid UTF-8 is returned.
-func safeTruncate(input string, limit int) string {
-	if trunc, ok := safeTruncateValidUTF8(input, limit); ok {
-		return trunc
+// truncate returns a truncated version of s such that it contains less than
+// the limit number of characters. Truncation is applied by returning the limit
+// number of valid characters contained in s.
+//
+// If limit is negative, it returns the original string.
+//
+// UTF-8 is supported. When truncating, all invalid characters are dropped
+// before applying truncation.
+//
+// If s already contains less than the limit number of bytes, it is returned
+// unchanged. No invalid characters are removed.
+func truncate(limit int, s string) string {
+	// This prioritize performance in the following order based on the most
+	// common expected use-cases.
+	//
+	//  - Short values less than the default limit (128).
+	//  - Strings with valid encodings that exceed the limit.
+	//  - No limit.
+	//  - Strings with invalid encodings that exceed the limit.
+	if limit < 0 || len(s) <= limit {
+		return s
 	}
-	trunc, _ := safeTruncateValidUTF8(strings.ToValidUTF8(input, ""), limit)
-	return trunc
-}
 
-// safeTruncateValidUTF8 returns a copy of the input string safely truncated to
-// limit. The truncation is ensured to occur at the bounds of complete UTF-8
-// characters. If invalid encoding of UTF-8 is encountered, input is returned
-// with false, otherwise, the truncated input will be returned with true.
-func safeTruncateValidUTF8(input string, limit int) (string, bool) {
-	for cnt := 0; cnt <= limit; {
-		r, size := utf8.DecodeRuneInString(input[cnt:])
-		if r == utf8.RuneError {
-			return input, false
+	// Optimistically, assume all valid UTF-8.
+	var b strings.Builder
+	count := 0
+	for i, c := range s {
+		if c != utf8.RuneError {
+			count++
+			if count > limit {
+				return s[:i]
+			}
+			continue
 		}
 
-		if cnt+size > limit {
-			return input[:cnt], true
+		_, size := utf8.DecodeRuneInString(s[i:])
+		if size == 1 {
+			// Invalid encoding.
+			b.Grow(len(s) - 1)
+			_, _ = b.WriteString(s[:i])
+			s = s[i:]
+			break
 		}
-		cnt += size
 	}
-	return input, true
+
+	// Fast-path, no invalid input.
+	if b.Cap() == 0 {
+		return s
+	}
+
+	// Truncate while validating UTF-8.
+	for i := 0; i < len(s) && count < limit; {
+		c := s[i]
+		if c < utf8.RuneSelf {
+			// Optimization for single byte runes (common case).
+			_ = b.WriteByte(c)
+			i++
+			count++
+			continue
+		}
+
+		_, size := utf8.DecodeRuneInString(s[i:])
+		if size == 1 {
+			// We checked for all 1-byte runes above, this is a RuneError.
+			i++
+			continue
+		}
+
+		_, _ = b.WriteString(s[i : i+size])
+		i += size
+		count++
+	}
+
+	return b.String()
 }
 
 // End ends the span. This method does nothing if the span is already ended or
 // is not being recorded.
 //
-// The only SpanOption currently supported is WithTimestamp which will set the
-// end time for a Span's life-cycle.
+// The only SpanEndOption currently supported are [trace.WithTimestamp], and
+// [trace.WithStackTrace].
 //
 // If this method is called while panicking an error event is added to the
 // Span before ending it and the panic is continued.
@@ -386,9 +454,10 @@ func (s *recordingSpan) End(options ...trace.SpanEndOption) {
 	// the span's duration in case some operation below takes a while.
 	et := monotonicEndTime(s.startTime)
 
-	// Do relative expensive check now that we have an end time and see if we
-	// need to do any more processing.
-	if !s.IsRecording() {
+	// Lock the span now that we have an end time and see if we need to do any more processing.
+	s.mu.Lock()
+	if !s.isRecording() {
+		s.mu.Unlock()
 		return
 	}
 
@@ -413,10 +482,11 @@ func (s *recordingSpan) End(options ...trace.SpanEndOption) {
 	}
 
 	if s.executionTracerTaskEnd != nil {
+		s.mu.Unlock()
 		s.executionTracerTaskEnd()
+		s.mu.Lock()
 	}
 
-	s.mu.Lock()
 	// Setting endTime to non-zero marks the span as ended and not recording.
 	if config.Timestamp().IsZero() {
 		s.endTime = et
@@ -450,7 +520,13 @@ func monotonicEndTime(start time.Time) time.Time {
 // does not change the Span status. If this span is not being recorded or err is nil
 // than this method does nothing.
 func (s *recordingSpan) RecordError(err error, opts ...trace.EventOption) {
-	if s == nil || err == nil || !s.IsRecording() {
+	if s == nil || err == nil {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.isRecording() {
 		return
 	}
 
@@ -486,14 +562,23 @@ func recordStackTrace() string {
 }
 
 // AddEvent adds an event with the provided name and options. If this span is
-// not being recorded than this method does nothing.
+// not being recorded then this method does nothing.
 func (s *recordingSpan) AddEvent(name string, o ...trace.EventOption) {
-	if !s.IsRecording() {
+	if s == nil {
+		return
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.isRecording() {
 		return
 	}
 	s.addEvent(name, o...)
 }
 
+// addEvent adds an event with the provided name and options.
+//
+// This method assumes s.mu.Lock is held by the caller.
 func (s *recordingSpan) addEvent(name string, o ...trace.EventOption) {
 	c := trace.NewEventConfig(o...)
 	e := Event{Name: name, Attributes: c.Attributes(), Time: c.Timestamp()}
@@ -510,20 +595,21 @@ func (s *recordingSpan) addEvent(name string, o ...trace.EventOption) {
 		e.Attributes = e.Attributes[:limit]
 	}
 
-	s.mu.Lock()
 	s.events.add(e)
-	s.mu.Unlock()
 }
 
 // SetName sets the name of this span. If this span is not being recorded than
 // this method does nothing.
 func (s *recordingSpan) SetName(name string) {
-	if !s.IsRecording() {
+	if s == nil {
 		return
 	}
 
 	s.mu.Lock()
 	defer s.mu.Unlock()
+	if !s.isRecording() {
+		return
+	}
 	s.name = name
 }
 
@@ -579,29 +665,26 @@ func (s *recordingSpan) Attributes() []attribute.KeyValue {
 func (s *recordingSpan) dedupeAttrs() {
 	// Do not set a capacity when creating this map. Benchmark testing has
 	// showed this to only add unused memory allocations in general use.
-	exists := make(map[attribute.Key]int)
-	s.dedupeAttrsFromRecord(&exists)
+	exists := make(map[attribute.Key]int, len(s.attributes))
+	s.dedupeAttrsFromRecord(exists)
 }
 
 // dedupeAttrsFromRecord deduplicates the attributes of s to fit capacity
 // using record as the record of unique attribute keys to their index.
 //
 // This method assumes s.mu.Lock is held by the caller.
-func (s *recordingSpan) dedupeAttrsFromRecord(record *map[attribute.Key]int) {
+func (s *recordingSpan) dedupeAttrsFromRecord(record map[attribute.Key]int) {
 	// Use the fact that slices share the same backing array.
 	unique := s.attributes[:0]
 	for _, a := range s.attributes {
-		if idx, ok := (*record)[a.Key]; ok {
+		if idx, ok := record[a.Key]; ok {
 			unique[idx] = a
 		} else {
 			unique = append(unique, a)
-			(*record)[a.Key] = len(unique) - 1
+			record[a.Key] = len(unique) - 1
 		}
 	}
-	// s.attributes have element types of attribute.KeyValue. These types are
-	// not pointers and they themselves do not contain pointer fields,
-	// therefore the duplicate values do not need to be zeroed for them to be
-	// garbage collected.
+	clear(s.attributes[len(unique):]) // Erase unneeded elements to let GC collect objects.
 	s.attributes = unique
 }
 
@@ -657,7 +740,7 @@ func (s *recordingSpan) Resource() *resource.Resource {
 }
 
 func (s *recordingSpan) AddLink(link trace.Link) {
-	if !s.IsRecording() {
+	if s == nil {
 		return
 	}
 	if !link.SpanContext.IsValid() && len(link.Attributes) == 0 &&
@@ -665,6 +748,12 @@ func (s *recordingSpan) AddLink(link trace.Link) {
 		return
 	}
 
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.isRecording() {
+		return
+	}
+
 	l := Link{SpanContext: link.SpanContext, Attributes: link.Attributes}
 
 	// Discard attributes over limit.
@@ -678,9 +767,7 @@ func (s *recordingSpan) AddLink(link trace.Link) {
 		l.Attributes = l.Attributes[:limit]
 	}
 
-	s.mu.Lock()
 	s.links.add(l)
-	s.mu.Unlock()
 }
 
 // DroppedAttributes returns the number of attributes dropped by the span
@@ -755,12 +842,16 @@ func (s *recordingSpan) snapshot() ReadOnlySpan {
 }
 
 func (s *recordingSpan) addChild() {
-	if !s.IsRecording() {
+	if s == nil {
 		return
 	}
+
 	s.mu.Lock()
+	defer s.mu.Unlock()
+	if !s.isRecording() {
+		return
+	}
 	s.childSpanCount++
-	s.mu.Unlock()
 }
 
 func (*recordingSpan) private() {}

vendor/go.opentelemetry.io/otel/sdk/version.go

@@ -5,5 +5,5 @@ package sdk // import "go.opentelemetry.io/otel/sdk"
 
 // Version is the current release version of the OpenTelemetry SDK in use.
 func Version() string {
-	return "1.29.0"
+	return "1.34.0"
 }

vendor/go.opentelemetry.io/otel/trace/config.go

@@ -213,7 +213,7 @@ var _ SpanStartEventOption = attributeOption{}
 
 // WithAttributes adds the attributes related to a span life-cycle event.
 // These attributes are used to describe the work a Span represents when this
-// option is provided to a Span's start or end events. Otherwise, these
+// option is provided to a Span's start event. Otherwise, these
 // attributes provide additional information about the event being recorded
 // (e.g. error, state change, processing progress, system event).
 //

vendor/go.opentelemetry.io/otel/trace/context.go

@@ -22,7 +22,7 @@ func ContextWithSpanContext(parent context.Context, sc SpanContext) context.Cont
 	return ContextWithSpan(parent, nonRecordingSpan{sc: sc})
 }
 
-// ContextWithRemoteSpanContext returns a copy of parent with rsc set explicly
+// ContextWithRemoteSpanContext returns a copy of parent with rsc set explicitly
 // as a remote SpanContext and as the current Span. The Span implementation
 // that wraps rsc is non-recording and performs no operations other than to
 // return rsc as the SpanContext from the SpanContext method.

vendor/go.opentelemetry.io/otel/trace/doc.go

@@ -96,7 +96,7 @@ can embed the API interface directly.
 
 This option is not recommended. It will lead to publishing packages that
 contain runtime panics when users update to newer versions of
-[go.opentelemetry.io/otel/trace], which may be done with a trasitive
+[go.opentelemetry.io/otel/trace], which may be done with a transitive
 dependency.
 
 Finally, an author can embed another implementation in theirs. The embedded

vendor/go.opentelemetry.io/otel/verify_examples.sh

@@ -1,74 +0,0 @@
-#!/bin/bash
-
-# Copyright The OpenTelemetry Authors
-# SPDX-License-Identifier: Apache-2.0
-
-set -euo pipefail
-
-cd $(dirname $0)
-TOOLS_DIR=$(pwd)/.tools
-
-if [ -z "${GOPATH}" ] ; then
-	printf "GOPATH is not defined.\n"
-	exit -1
-fi
-
-if [ ! -d "${GOPATH}" ] ; then
-	printf "GOPATH ${GOPATH} is invalid \n"
-	exit -1
-fi
-
-# Pre-requisites
-if ! git diff --quiet; then \
-	git status
-	printf "\n\nError: working tree is not clean\n"
-	exit -1
-fi
-
-if [ "$(git tag --contains $(git log -1 --pretty=format:"%H"))" = "" ] ; then
-	printf "$(git log -1)"
-	printf "\n\nError: HEAD is not pointing to a tagged version"
-fi
-
-make ${TOOLS_DIR}/gojq
-
-DIR_TMP="${GOPATH}/src/oteltmp/"
-rm -rf $DIR_TMP
-mkdir -p $DIR_TMP
-
-printf "Copy examples to ${DIR_TMP}\n"
-cp -a ./example ${DIR_TMP}
-
-# Update go.mod files
-printf "Update go.mod: rename module and remove replace\n"
-
-PACKAGE_DIRS=$(find . -mindepth 2 -type f -name 'go.mod' -exec dirname {} \; | egrep 'example' | sed 's/^\.\///' | sort)
-
-for dir in $PACKAGE_DIRS; do
-	printf "  Update go.mod for $dir\n"
-	(cd "${DIR_TMP}/${dir}" && \
-	 # replaces is ("mod1" "mod2" …)
-	 replaces=($(go mod edit -json | ${TOOLS_DIR}/gojq '.Replace[].Old.Path')) && \
-	 # strip double quotes
-	 replaces=("${replaces[@]%\"}") && \
-	 replaces=("${replaces[@]#\"}") && \
-	 # make an array (-dropreplace=mod1 -dropreplace=mod2 …)
-	 dropreplaces=("${replaces[@]/#/-dropreplace=}") && \
-	 go mod edit -module "oteltmp/${dir}" "${dropreplaces[@]}" && \
-	 go mod tidy)
-done
-printf "Update done:\n\n"
-
-# Build directories that contain main package. These directories are different than
-# directories that contain go.mod files.
-printf "Build examples:\n"
-EXAMPLES=$(./get_main_pkgs.sh ./example)
-for ex in $EXAMPLES; do
-	printf "  Build $ex in ${DIR_TMP}/${ex}\n"
-	(cd "${DIR_TMP}/${ex}" && \
-	 go build .)
-done
-
-# Cleanup
-printf "Remove copied files.\n"
-rm -rf $DIR_TMP

vendor/go.opentelemetry.io/otel/version.go

@@ -5,5 +5,5 @@ package otel // import "go.opentelemetry.io/otel"
 
 // Version is the current release version of OpenTelemetry in use.
 func Version() string {
-	return "1.29.0"
+	return "1.34.0"
 }

vendor/go.opentelemetry.io/otel/versions.yaml

@@ -3,19 +3,13 @@
 
 module-sets:
   stable-v1:
-    version: v1.29.0
+    version: v1.34.0
     modules:
       - go.opentelemetry.io/otel
       - go.opentelemetry.io/otel/bridge/opencensus
       - go.opentelemetry.io/otel/bridge/opencensus/test
       - go.opentelemetry.io/otel/bridge/opentracing
       - go.opentelemetry.io/otel/bridge/opentracing/test
-      - go.opentelemetry.io/otel/example/dice
-      - go.opentelemetry.io/otel/example/namedtracer
-      - go.opentelemetry.io/otel/example/opencensus
-      - go.opentelemetry.io/otel/example/otel-collector
-      - go.opentelemetry.io/otel/example/passthrough
-      - go.opentelemetry.io/otel/example/zipkin
       - go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc
       - go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp
       - go.opentelemetry.io/otel/exporters/otlp/otlptrace
@@ -29,12 +23,11 @@ module-sets:
       - go.opentelemetry.io/otel/sdk/metric
       - go.opentelemetry.io/otel/trace
   experimental-metrics:
-    version: v0.51.0
+    version: v0.56.0
     modules:
-      - go.opentelemetry.io/otel/example/prometheus
       - go.opentelemetry.io/otel/exporters/prometheus
   experimental-logs:
-    version: v0.5.0
+    version: v0.10.0
     modules:
       - go.opentelemetry.io/otel/log
       - go.opentelemetry.io/otel/sdk/log
@@ -42,7 +35,7 @@ module-sets:
       - go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp
       - go.opentelemetry.io/otel/exporters/stdout/stdoutlog
   experimental-schema:
-    version: v0.0.8
+    version: v0.0.12
     modules:
       - go.opentelemetry.io/otel/schema
 excluded-modules: