[chore] Bump all otel deps (#3241)

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

@@ -4,6 +4,8 @@
 package tracetransform // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
 
 import (
+	"math"
+
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/sdk/instrumentation"
@@ -102,9 +104,9 @@ func span(sd tracesdk.ReadOnlySpan) *tracepb.Span {
 		Name:                   sd.Name(),
 		Attributes:             KeyValues(sd.Attributes()),
 		Events:                 spanEvents(sd.Events()),
-		DroppedAttributesCount: uint32(sd.DroppedAttributes()),
-		DroppedEventsCount:     uint32(sd.DroppedEvents()),
-		DroppedLinksCount:      uint32(sd.DroppedLinks()),
+		DroppedAttributesCount: clampUint32(sd.DroppedAttributes()),
+		DroppedEventsCount:     clampUint32(sd.DroppedEvents()),
+		DroppedLinksCount:      clampUint32(sd.DroppedLinks()),
 	}
 
 	if psid := sd.Parent().SpanID(); psid.IsValid() {
@@ -115,6 +117,16 @@ func span(sd tracesdk.ReadOnlySpan) *tracepb.Span {
 	return s
 }
 
+func clampUint32(v int) uint32 {
+	if v < 0 {
+		return 0
+	}
+	if int64(v) > math.MaxUint32 {
+		return math.MaxUint32
+	}
+	return uint32(v) // nolint: gosec  // Overflow/Underflow checked.
+}
+
 // status transform a span code and message into an OTLP span status.
 func status(status codes.Code, message string) *tracepb.Status {
 	var c tracepb.Status_StatusCode
@@ -153,7 +165,7 @@ func links(links []tracesdk.Link) []*tracepb.Span_Link {
 			TraceId:                tid[:],
 			SpanId:                 sid[:],
 			Attributes:             KeyValues(otLink.Attributes),
-			DroppedAttributesCount: uint32(otLink.DroppedAttributeCount),
+			DroppedAttributesCount: clampUint32(otLink.DroppedAttributeCount),
 			Flags:                  flags,
 		})
 	}
@@ -182,7 +194,7 @@ func spanEvents(es []tracesdk.Event) []*tracepb.Span_Event {
 			Name:                   es[i].Name,
 			TimeUnixNano:           uint64(es[i].Time.UnixNano()),
 			Attributes:             KeyValues(es[i].Attributes),
-			DroppedAttributesCount: uint32(es[i].DroppedAttributeCount),
+			DroppedAttributesCount: clampUint32(es[i].DroppedAttributeCount),
 		}
 	}
 	return events

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

@@ -12,9 +12,8 @@ The environment variables described below can be used for configuration.
 OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT (default: "https://localhost:4317") -
 target to which the exporter sends telemetry.
 The target syntax is defined in https://github.com/grpc/grpc/blob/master/doc/naming.md.
-The value must contain a host.
-The value may additionally a port, a scheme, and a path.
-The value accepts "http" and "https" scheme.
+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.
 OTEL_EXPORTER_OTLP_TRACES_ENDPOINT takes precedence over OTEL_EXPORTER_OTLP_ENDPOINT.
 The configuration can be overridden by [WithEndpoint], [WithEndpointURL], [WithInsecure], and [WithGRPCConn] options.

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

@@ -15,6 +15,7 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	"unicode"
 
 	"go.opentelemetry.io/otel/internal/global"
 )
@@ -163,12 +164,16 @@ func stringToHeader(value string) map[string]string {
 			global.Error(errors.New("missing '="), "parse headers", "input", header)
 			continue
 		}
-		name, err := url.PathUnescape(n)
-		if err != nil {
-			global.Error(err, "escape header key", "key", n)
+
+		trimmedName := strings.TrimSpace(n)
+
+		// Validate the key.
+		if !isValidHeaderKey(trimmedName) {
+			global.Error(errors.New("invalid header key"), "parse headers", "key", trimmedName)
 			continue
 		}
-		trimmedName := strings.TrimSpace(name)
+
+		// Only decode the value.
 		value, err := url.PathUnescape(v)
 		if err != nil {
 			global.Error(err, "escape header value", "value", v)
@@ -189,3 +194,22 @@ func createCertPool(certBytes []byte) (*x509.CertPool, error) {
 	}
 	return cp, nil
 }
+
+func isValidHeaderKey(key string) bool {
+	if key == "" {
+		return false
+	}
+	for _, c := range key {
+		if !isTokenChar(c) {
+			return false
+		}
+	}
+	return true
+}
+
+func isTokenChar(c rune) bool {
+	return c <= unicode.MaxASCII && (unicode.IsLetter(c) ||
+		unicode.IsDigit(c) ||
+		c == '!' || c == '#' || c == '$' || c == '%' || c == '&' || c == '\'' || c == '*' ||
+		c == '+' || c == '-' || c == '.' || c == '^' || c == '_' || c == '`' || c == '|' || c == '~')
+}

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

@@ -256,6 +256,9 @@ func NewGRPCOption(fn func(cfg Config) Config) GRPCOption {
 
 // Generic Options
 
+// WithEndpoint configures the trace host and port only; endpoint should
+// resemble "example.com" or "localhost:4317". To configure the scheme and path,
+// use WithEndpointURL.
 func WithEndpoint(endpoint string) GenericOption {
 	return newGenericOption(func(cfg Config) Config {
 		cfg.Traces.Endpoint = endpoint
@@ -263,6 +266,8 @@ func WithEndpoint(endpoint string) GenericOption {
 	})
 }
 
+// WithEndpointURL configures the trace scheme, host, port, and path; the
+// provided value should resemble "https://example.com:4318/v1/traces".
 func WithEndpointURL(v string) GenericOption {
 	return newGenericOption(func(cfg Config) Config {
 		u, err := url.Parse(v)

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

@@ -112,7 +112,7 @@ func (c Config) RequestFunc(evaluate EvaluateFunc) RequestFunc {
 			}
 
 			if ctxErr := waitFunc(ctx, delay); ctxErr != nil {
-				return fmt.Errorf("%w: %s", ctxErr, err)
+				return fmt.Errorf("%w: %w", ctxErr, err)
 			}
 		}
 	}

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

@@ -53,12 +53,15 @@ func WithInsecure() Option {
 	return wrappedOption{otlpconfig.WithInsecure()}
 }
 
-// WithEndpoint sets the target endpoint the Exporter will connect to.
+// WithEndpoint sets the target endpoint (host and port) the Exporter will
+// connect to. The provided endpoint should resemble "example.com:4317" (no
+// scheme or path).
 //
-// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
+// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
 // environment variable is set, and this option is not passed, that variable
-// value will be used. If both are set, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
-// will take precedence.
+// value will be used. If both environment variables are set,
+// OTEL_EXPORTER_OTLP_TRACES_ENDPOINT will take precedence. If an environment
+// variable is set, and this option is passed, this option will take precedence.
 //
 // If both this option and WithEndpointURL are used, the last used option will
 // take precedence.
@@ -71,12 +74,15 @@ func WithEndpoint(endpoint string) Option {
 	return wrappedOption{otlpconfig.WithEndpoint(endpoint)}
 }
 
-// WithEndpointURL sets the target endpoint URL the Exporter will connect to.
+// WithEndpointURL sets the target endpoint URL (scheme, host, port, path)
+// the Exporter will connect to. The provided endpoint URL should resemble
+// "https://example.com:4318/v1/traces".
 //
-// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
+// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
 // environment variable is set, and this option is not passed, that variable
-// value will be used. If both are set, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
-// will take precedence.
+// value will be used. If both environment variables are set,
+// OTEL_EXPORTER_OTLP_TRACES_ENDPOINT will take precedence. If an environment
+// variable is set, and this option is passed, this option will take precedence.
 //
 // If both this option and WithEndpoint are used, the last used option will
 // take precedence.
@@ -84,7 +90,7 @@ func WithEndpoint(endpoint string) Option {
 // If an invalid URL is provided, the default value will be kept.
 //
 // By default, if an environment variable is not set, and this option is not
-// passed, "localhost:4317" will be used.
+// passed, "https://localhost:4317/v1/traces" will be used.
 //
 // This option has no effect if WithGRPCConn is used.
 func WithEndpointURL(u string) Option {

vendor/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/README.md

@@ -0,0 +1,3 @@
+# OTLP Trace HTTP Exporter
+
+[![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp)](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp)

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlptracehttp // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
 
@@ -25,6 +14,7 @@ import (
 	"net/http"
 	"net/url"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 
@@ -85,10 +75,17 @@ func NewClient(opts ...Option) otlptrace.Client {
 		Transport: ourTransport,
 		Timeout:   cfg.Traces.Timeout,
 	}
-	if cfg.Traces.TLSCfg != nil {
-		transport := ourTransport.Clone()
-		transport.TLSClientConfig = cfg.Traces.TLSCfg
-		httpClient.Transport = transport
+
+	if cfg.Traces.TLSCfg != nil || cfg.Traces.Proxy != nil {
+		clonedTransport := ourTransport.Clone()
+		httpClient.Transport = clonedTransport
+
+		if cfg.Traces.TLSCfg != nil {
+			clonedTransport.TLSClientConfig = cfg.Traces.TLSCfg
+		}
+		if cfg.Traces.Proxy != nil {
+			clonedTransport.Proxy = cfg.Traces.Proxy
+		}
 	}
 
 	stopCh := make(chan struct{})
@@ -155,7 +152,7 @@ func (d *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.Resourc
 		resp, err := d.client.Do(request.Request)
 		var urlErr *url.Error
 		if errors.As(err, &urlErr) && urlErr.Temporary() {
-			return newResponseError(http.Header{})
+			return newResponseError(http.Header{}, err)
 		}
 		if err != nil {
 			return err
@@ -202,11 +199,27 @@ func (d *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.Resourc
 			sc == http.StatusBadGateway,
 			sc == http.StatusServiceUnavailable,
 			sc == http.StatusGatewayTimeout:
-			// Retry-able failures.  Drain the body to reuse the connection.
-			if _, err := io.Copy(io.Discard, resp.Body); err != nil {
-				otel.Handle(err)
+			// 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 {
+				_ = resp.Body.Close()
+				return err
 			}
-			return newResponseError(resp.Header)
+
+			// 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
 		default:
 			return fmt.Errorf("failed to send to %s: %s", request.URL, resp.Status)
 		}
@@ -247,7 +260,7 @@ func (d *client) newRequest(body []byte) (request, error) {
 		if _, err := gz.Write(body); err != nil {
 			return req, err
 		}
-		// Close needs to be called to ensure body if fully written.
+		// Close needs to be called to ensure body is fully written.
 		if err := gz.Close(); err != nil {
 			return req, err
 		}
@@ -295,24 +308,50 @@ func (r *request) reset(ctx context.Context) {
 // retryableError represents a request failure that can be retried.
 type retryableError struct {
 	throttle int64
+	err      error
 }
 
 // newResponseError returns a retryableError and will extract any explicit
-// throttle delay contained in headers.
-func newResponseError(header http.Header) error {
+// throttle delay contained in headers. The returned error wraps wrapped
+// if it is not nil.
+func newResponseError(header http.Header, wrapped error) error {
 	var rErr retryableError
 	if s, ok := header["Retry-After"]; ok {
 		if t, err := strconv.ParseInt(s[0], 10, 64); err == nil {
 			rErr.throttle = t
 		}
 	}
+
+	rErr.err = wrapped
 	return rErr
 }
 
 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"
 }
 
+func (e retryableError) Unwrap() error {
+	return e.err
+}
+
+func (e retryableError) As(target interface{}) bool {
+	if e.err == nil {
+		return false
+	}
+
+	switch v := target.(type) {
+	case **retryableError:
+		*v = &e
+		return true
+	default:
+		return false
+	}
+}
+
 // evaluate returns if err is retry-able. If it is and it includes an explicit
 // throttling delay, that delay is also returned.
 func evaluate(err error) (bool, time.Duration) {
@@ -320,7 +359,10 @@ func evaluate(err error) (bool, time.Duration) {
 		return false, 0
 	}
 
-	rErr, ok := err.(retryableError)
+	// Do not use errors.As here, this should only be flattened one layer. If
+	// there are several chained errors, all the errors above it will be
+	// discarded if errors.As is used instead.
+	rErr, ok := err.(retryableError) //nolint:errorlint
 	if !ok {
 		return false, 0
 	}

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 /*
 Package otlptracehttp provides an OTLP span exporter using HTTP with protobuf payloads.
@@ -37,7 +26,7 @@ The configuration can be overridden by [WithEndpoint], [WithEndpointURL], [WitnI
 
 OTEL_EXPORTER_OTLP_HEADERS, OTEL_EXPORTER_OTLP_TRACES_HEADERS (default: none) -
 key-value pairs used as headers associated with HTTP requests.
-The value is expected to be represented in a format matching to the [W3C Baggage HTTP Header Content Format],
+The value is expected to be represented in a format matching the [W3C Baggage HTTP Header Content Format],
 except that additional semi-colon delimited metadata is not supported.
 Example value: "key1=value1,key2=value2".
 OTEL_EXPORTER_OTLP_TRACES_HEADERS takes precedence over OTEL_EXPORTER_OTLP_HEADERS.
@@ -60,12 +49,12 @@ OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE takes precedence over OTEL_EXPORTER_OTLP_C
 The configuration can be overridden by [WithTLSClientConfig] option.
 
 OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE, OTEL_EXPORTER_OTLP_TRACES_CLIENT_CERTIFICATE (default: none) -
-the filepath to the client certificate/chain trust for clients private key to use in mTLS communication in PEM format.
+the filepath to the client certificate/chain trust for client's private key to use in mTLS communication in PEM format.
 OTEL_EXPORTER_OTLP_TRACES_CLIENT_CERTIFICATE takes precedence over OTEL_EXPORTER_OTLP_CLIENT_CERTIFICATE.
 The configuration can be overridden by [WithTLSClientConfig] option.
 
 OTEL_EXPORTER_OTLP_CLIENT_KEY, OTEL_EXPORTER_OTLP_TRACES_CLIENT_KEY (default: none) -
-the filepath  to the clients private key to use in mTLS communication in PEM format.
+the filepath to the client's private key to use in mTLS communication in PEM format.
 OTEL_EXPORTER_OTLP_TRACES_CLIENT_KEY takes precedence over OTEL_EXPORTER_OTLP_CLIENT_KEY.
 The configuration can be overridden by [WithTLSClientConfig] option.
 

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlptracehttp // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
 

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/envconfig/envconfig.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package envconfig // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/envconfig"
 
@@ -26,6 +15,7 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	"unicode"
 
 	"go.opentelemetry.io/otel/internal/global"
 )
@@ -174,12 +164,16 @@ func stringToHeader(value string) map[string]string {
 			global.Error(errors.New("missing '="), "parse headers", "input", header)
 			continue
 		}
-		name, err := url.PathUnescape(n)
-		if err != nil {
-			global.Error(err, "escape header key", "key", n)
+
+		trimmedName := strings.TrimSpace(n)
+
+		// Validate the key.
+		if !isValidHeaderKey(trimmedName) {
+			global.Error(errors.New("invalid header key"), "parse headers", "key", trimmedName)
 			continue
 		}
-		trimmedName := strings.TrimSpace(name)
+
+		// Only decode the value.
 		value, err := url.PathUnescape(v)
 		if err != nil {
 			global.Error(err, "escape header value", "value", v)
@@ -200,3 +194,22 @@ func createCertPool(certBytes []byte) (*x509.CertPool, error) {
 	}
 	return cp, nil
 }
+
+func isValidHeaderKey(key string) bool {
+	if key == "" {
+		return false
+	}
+	for _, c := range key {
+		if !isTokenChar(c) {
+			return false
+		}
+	}
+	return true
+}
+
+func isTokenChar(c rune) bool {
+	return c <= unicode.MaxASCII && (unicode.IsLetter(c) ||
+		unicode.IsDigit(c) ||
+		c == '!' || c == '#' || c == '$' || c == '%' || c == '&' || c == '\'' || c == '*' ||
+		c == '+' || c == '-' || c == '.' || c == '^' || c == '_' || c == '`' || c == '|' || c == '~')
+}

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package internal // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal"
 

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/otlptrace/otlpconfig/envconfig.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlpconfig // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig"
 

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

@@ -2,24 +2,14 @@
 // source: internal/shared/otlp/otlptrace/otlpconfig/options.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlpconfig // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig"
 
 import (
 	"crypto/tls"
 	"fmt"
+	"net/http"
 	"net/url"
 	"path"
 	"strings"
@@ -46,6 +36,10 @@ const (
 )
 
 type (
+	// HTTPTransportProxyFunc is a function that resolves which URL to use as proxy for a given request.
+	// This type is compatible with `http.Transport.Proxy` and can be used to set a custom proxy function to the OTLP HTTP client.
+	HTTPTransportProxyFunc func(*http.Request) (*url.URL, error)
+
 	SignalConfig struct {
 		Endpoint    string
 		Insecure    bool
@@ -57,6 +51,8 @@ type (
 
 		// gRPC configurations
 		GRPCCredentials credentials.TransportCredentials
+
+		Proxy HTTPTransportProxyFunc
 	}
 
 	Config struct {
@@ -260,6 +256,9 @@ func NewGRPCOption(fn func(cfg Config) Config) GRPCOption {
 
 // Generic Options
 
+// WithEndpoint configures the trace host and port only; endpoint should
+// resemble "example.com" or "localhost:4317". To configure the scheme and path,
+// use WithEndpointURL.
 func WithEndpoint(endpoint string) GenericOption {
 	return newGenericOption(func(cfg Config) Config {
 		cfg.Traces.Endpoint = endpoint
@@ -267,6 +266,8 @@ func WithEndpoint(endpoint string) GenericOption {
 	})
 }
 
+// WithEndpointURL configures the trace scheme, host, port, and path; the
+// provided value should resemble "https://example.com:4318/v1/traces".
 func WithEndpointURL(v string) GenericOption {
 	return newGenericOption(func(cfg Config) Config {
 		u, err := url.Parse(v)
@@ -343,3 +344,10 @@ func WithTimeout(duration time.Duration) GenericOption {
 		return cfg
 	})
 }
+
+func WithProxy(pf HTTPTransportProxyFunc) GenericOption {
+	return newGenericOption(func(cfg Config) Config {
+		cfg.Traces.Proxy = pf
+		return cfg
+	})
+}

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/otlptrace/otlpconfig/optiontypes.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlpconfig // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig"
 

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/otlptrace/otlpconfig/tls.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlpconfig // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig"
 

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/partialsuccess.go
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package internal // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal"
 

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

@@ -2,18 +2,7 @@
 // source: internal/shared/otlp/retry/retry.go.tmpl
 
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 // Package retry provides request retry functionality that can perform
 // configurable exponential backoff for transient errors and honor any
@@ -123,7 +112,7 @@ func (c Config) RequestFunc(evaluate EvaluateFunc) RequestFunc {
 			}
 
 			if ctxErr := waitFunc(ctx, delay); ctxErr != nil {
-				return fmt.Errorf("%w: %s", ctxErr, err)
+				return fmt.Errorf("%w: %w", ctxErr, err)
 			}
 		}
 	}

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

@@ -1,21 +1,12 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package otlptracehttp // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
 
 import (
 	"crypto/tls"
+	"net/http"
+	"net/url"
 	"time"
 
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp/internal/otlpconfig"
@@ -26,6 +17,11 @@ import (
 // collector.
 type Compression otlpconfig.Compression
 
+// HTTPTransportProxyFunc is a function that resolves which URL to use as proxy for a given request.
+// This type is compatible with http.Transport.Proxy and can be used to set a custom proxy function
+// to the OTLP HTTP client.
+type HTTPTransportProxyFunc func(*http.Request) (*url.URL, error)
+
 const (
 	// NoCompression tells the driver to send payloads without
 	// compression.
@@ -60,30 +56,37 @@ func (w wrappedOption) applyHTTPOption(cfg otlpconfig.Config) otlpconfig.Config
 	return w.ApplyHTTPOption(cfg)
 }
 
-// WithEndpoint sets the target endpoint the Exporter will connect to.
+// WithEndpoint sets the target endpoint (host and port) the Exporter will
+// connect to. The provided endpoint should resemble "example.com:4318" (no
+// scheme or path).
 //
-// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
+// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
 // environment variable is set, and this option is not passed, that variable
-// value will be used. If both are set, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
-// will take precedence.
+// value will be used. If both environment variables are set,
+// OTEL_EXPORTER_OTLP_TRACES_ENDPOINT will take precedence. If an environment
+// variable is set, and this option is passed, this option will take precedence.
+// Note, both environment variables include the full
+// scheme and path, while WithEndpoint sets only the host and port.
 //
 // If both this option and WithEndpointURL are used, the last used option will
 // take precedence.
 //
 // By default, if an environment variable is not set, and this option is not
-// passed, "localhost:4317" will be used.
+// passed, "localhost:4318" will be used.
 //
 // This option has no effect if WithGRPCConn is used.
 func WithEndpoint(endpoint string) Option {
 	return wrappedOption{otlpconfig.WithEndpoint(endpoint)}
 }
 
-// WithEndpointURL sets the target endpoint URL the Exporter will connect to.
+// WithEndpointURL sets the target endpoint URL (scheme, host, port, path) the
+// Exporter will connect to.
 //
-// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
+// If the OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
 // environment variable is set, and this option is not passed, that variable
-// value will be used. If both are set, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
-// will take precedence.
+// value will be used. If both environment variables are set,
+// OTEL_EXPORTER_OTLP_TRACES_ENDPOINT will take precedence. If an environment
+// variable is set, and this option is passed, this option will take precedence.
 //
 // If both this option and WithEndpoint are used, the last used option will
 // take precedence.
@@ -91,7 +94,7 @@ func WithEndpoint(endpoint string) Option {
 // If an invalid URL is provided, the default value will be kept.
 //
 // By default, if an environment variable is not set, and this option is not
-// passed, "localhost:4317" will be used.
+// passed, "localhost:4318" will be used.
 //
 // This option has no effect if WithGRPCConn is used.
 func WithEndpointURL(u string) Option {
@@ -143,3 +146,10 @@ func WithTimeout(duration time.Duration) Option {
 func WithRetry(rc RetryConfig) Option {
 	return wrappedOption{otlpconfig.WithRetry(retry.Config(rc))}
 }
+
+// WithProxy sets the Proxy function the client will use to determine the
+// proxy to use for an HTTP request. If this option is not used, the client
+// will use [http.ProxyFromEnvironment].
+func WithProxy(pf HTTPTransportProxyFunc) Option {
+	return wrappedOption{otlpconfig.WithProxy(otlpconfig.HTTPTransportProxyFunc(pf))}
+}

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 "1.26.0"
+	return "1.29.0"
 }

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

@@ -0,0 +1,3 @@
+# Prometheus Exporter
+
+[![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel/exporters/prometheus)](https://pkg.go.dev/go.opentelemetry.io/otel/exporters/prometheus)

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package prometheus // import "go.opentelemetry.io/otel/exporters/prometheus"
 

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

@@ -1,16 +1,5 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 // Package prometheus provides a Prometheus Exporter that converts
 // OTLP metrics into the Prometheus exposition format and implements

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

@@ -1,24 +1,14 @@
 // Copyright The OpenTelemetry Authors
-//
-// 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.
+// SPDX-License-Identifier: Apache-2.0
 
 package prometheus // import "go.opentelemetry.io/otel/exporters/prometheus"
 
 import (
 	"context"
+	"encoding/hex"
 	"errors"
 	"fmt"
-	"sort"
+	"slices"
 	"strings"
 	"sync"
 	"unicode"
@@ -43,6 +33,9 @@ const (
 
 	scopeInfoMetricName  = "otel_scope_info"
 	scopeInfoDescription = "Instrumentation Scope metadata"
+
+	traceIDExemplarKey = "trace_id"
+	spanIDExemplarKey  = "span_id"
 )
 
 var (
@@ -199,7 +192,7 @@ func (c *collector) Collect(ch chan<- prometheus.Metric) {
 
 		if !c.disableScopeInfo {
 			scopeInfo, err := c.scopeInfo(scopeMetrics.Scope)
-			if err == errScopeInvalid {
+			if errors.Is(err, errScopeInvalid) {
 				// Do not report the same error multiple times.
 				continue
 			}
@@ -249,7 +242,6 @@ func (c *collector) Collect(ch chan<- prometheus.Metric) {
 }
 
 func addHistogramMetric[N int64 | float64](ch chan<- prometheus.Metric, histogram metricdata.Histogram[N], m metricdata.Metrics, ks, vs [2]string, name string, resourceKV keyVals) {
-	// TODO(https://github.com/open-telemetry/opentelemetry-go/issues/3163): support exemplars
 	for _, dp := range histogram.DataPoints {
 		keys, values := getAttrs(dp.Attributes, ks, vs, resourceKV)
 
@@ -266,6 +258,7 @@ func addHistogramMetric[N int64 | float64](ch chan<- prometheus.Metric, histogra
 			otel.Handle(err)
 			continue
 		}
+		m = addExemplars(m, dp.Exemplars)
 		ch <- m
 	}
 }
@@ -285,6 +278,7 @@ func addSumMetric[N int64 | float64](ch chan<- prometheus.Metric, sum metricdata
 			otel.Handle(err)
 			continue
 		}
+		m = addExemplars(m, dp.Exemplars)
 		ch <- m
 	}
 }
@@ -324,9 +318,7 @@ func getAttrs(attrs attribute.Set, ks, vs [2]string, resourceKV keyVals) ([]stri
 	values := make([]string, 0, attrs.Len())
 	for key, vals := range keysMap {
 		keys = append(keys, key)
-		sort.Slice(vals, func(i, j int) bool {
-			return i < j
-		})
+		slices.Sort(vals)
 		values = append(values, strings.Join(vals, ";"))
 	}
 
@@ -562,3 +554,37 @@ func (c *collector) validateMetrics(name, description string, metricType *dto.Me
 
 	return false, ""
 }
+
+func addExemplars[N int64 | float64](m prometheus.Metric, exemplars []metricdata.Exemplar[N]) prometheus.Metric {
+	if len(exemplars) == 0 {
+		return m
+	}
+	promExemplars := make([]prometheus.Exemplar, len(exemplars))
+	for i, exemplar := range exemplars {
+		labels := attributesToLabels(exemplar.FilteredAttributes)
+		// Overwrite any existing trace ID or span ID attributes
+		labels[traceIDExemplarKey] = hex.EncodeToString(exemplar.TraceID[:])
+		labels[spanIDExemplarKey] = hex.EncodeToString(exemplar.SpanID[:])
+		promExemplars[i] = prometheus.Exemplar{
+			Value:     float64(exemplar.Value),
+			Timestamp: exemplar.Time,
+			Labels:    labels,
+		}
+	}
+	metricWithExemplar, err := prometheus.NewMetricWithExemplars(m, promExemplars...)
+	if err != nil {
+		// If there are errors creating the metric with exemplars, just warn
+		// and return the metric without exemplars.
+		otel.Handle(err)
+		return m
+	}
+	return metricWithExemplar
+}
+
+func attributesToLabels(attrs []attribute.KeyValue) prometheus.Labels {
+	labels := make(map[string]string)
+	for _, attr := range attrs {
+		labels[string(attr.Key)] = attr.Value.Emit()
+	}
+	return labels
+}