feat: initial tracing support (#1623)

vendor/go.opentelemetry.io/otel/exporters/otlp/internal/config.go

@@ -0,0 +1,34 @@
+// 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.
+
+// Package internal contains common functionality for all OTLP exporters.
+package internal // import "go.opentelemetry.io/otel/exporters/otlp/internal"
+
+import (
+	"fmt"
+	"path"
+	"strings"
+)
+
+// CleanPath returns a path with all spaces trimmed and all redundancies removed. If urlPath is empty or cleaning it results in an empty string, defaultPath is returned instead.
+func CleanPath(urlPath string, defaultPath string) string {
+	tmp := path.Clean(strings.TrimSpace(urlPath))
+	if tmp == "." {
+		return defaultPath
+	}
+	if !path.IsAbs(tmp) {
+		tmp = fmt.Sprintf("/%s", tmp)
+	}
+	return tmp
+}

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

@@ -0,0 +1,199 @@
+// 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.
+
+package envconfig // import "go.opentelemetry.io/otel/exporters/otlp/internal/envconfig"
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"errors"
+	"fmt"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"go.opentelemetry.io/otel/internal/global"
+)
+
+// ConfigFn is the generic function used to set a config.
+type ConfigFn func(*EnvOptionsReader)
+
+// EnvOptionsReader reads the required environment variables.
+type EnvOptionsReader struct {
+	GetEnv    func(string) string
+	ReadFile  func(string) ([]byte, error)
+	Namespace string
+}
+
+// Apply runs every ConfigFn.
+func (e *EnvOptionsReader) Apply(opts ...ConfigFn) {
+	for _, o := range opts {
+		o(e)
+	}
+}
+
+// GetEnvValue gets an OTLP environment variable value of the specified key
+// using the GetEnv function.
+// This function prepends the OTLP specified namespace to all key lookups.
+func (e *EnvOptionsReader) GetEnvValue(key string) (string, bool) {
+	v := strings.TrimSpace(e.GetEnv(keyWithNamespace(e.Namespace, key)))
+	return v, v != ""
+}
+
+// WithString retrieves the specified config and passes it to ConfigFn as a string.
+func WithString(n string, fn func(string)) func(e *EnvOptionsReader) {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			fn(v)
+		}
+	}
+}
+
+// WithBool returns a ConfigFn that reads the environment variable n and if it exists passes its parsed bool value to fn.
+func WithBool(n string, fn func(bool)) ConfigFn {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			b := strings.ToLower(v) == "true"
+			fn(b)
+		}
+	}
+}
+
+// WithDuration retrieves the specified config and passes it to ConfigFn as a duration.
+func WithDuration(n string, fn func(time.Duration)) func(e *EnvOptionsReader) {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			d, err := strconv.Atoi(v)
+			if err != nil {
+				global.Error(err, "parse duration", "input", v)
+				return
+			}
+			fn(time.Duration(d) * time.Millisecond)
+		}
+	}
+}
+
+// WithHeaders retrieves the specified config and passes it to ConfigFn as a map of HTTP headers.
+func WithHeaders(n string, fn func(map[string]string)) func(e *EnvOptionsReader) {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			fn(stringToHeader(v))
+		}
+	}
+}
+
+// WithURL retrieves the specified config and passes it to ConfigFn as a net/url.URL.
+func WithURL(n string, fn func(*url.URL)) func(e *EnvOptionsReader) {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			u, err := url.Parse(v)
+			if err != nil {
+				global.Error(err, "parse url", "input", v)
+				return
+			}
+			fn(u)
+		}
+	}
+}
+
+// WithCertPool returns a ConfigFn that reads the environment variable n as a filepath to a TLS certificate pool. If it exists, it is parsed as a crypto/x509.CertPool and it is passed to fn.
+func WithCertPool(n string, fn func(*x509.CertPool)) ConfigFn {
+	return func(e *EnvOptionsReader) {
+		if v, ok := e.GetEnvValue(n); ok {
+			b, err := e.ReadFile(v)
+			if err != nil {
+				global.Error(err, "read tls ca cert file", "file", v)
+				return
+			}
+			c, err := createCertPool(b)
+			if err != nil {
+				global.Error(err, "create tls cert pool")
+				return
+			}
+			fn(c)
+		}
+	}
+}
+
+// WithClientCert returns a ConfigFn that reads the environment variable nc and nk as filepaths to a client certificate and key pair. If they exists, they are parsed as a crypto/tls.Certificate and it is passed to fn.
+func WithClientCert(nc, nk string, fn func(tls.Certificate)) ConfigFn {
+	return func(e *EnvOptionsReader) {
+		vc, okc := e.GetEnvValue(nc)
+		vk, okk := e.GetEnvValue(nk)
+		if !okc || !okk {
+			return
+		}
+		cert, err := e.ReadFile(vc)
+		if err != nil {
+			global.Error(err, "read tls client cert", "file", vc)
+			return
+		}
+		key, err := e.ReadFile(vk)
+		if err != nil {
+			global.Error(err, "read tls client key", "file", vk)
+			return
+		}
+		crt, err := tls.X509KeyPair(cert, key)
+		if err != nil {
+			global.Error(err, "create tls client key pair")
+			return
+		}
+		fn(crt)
+	}
+}
+
+func keyWithNamespace(ns, key string) string {
+	if ns == "" {
+		return key
+	}
+	return fmt.Sprintf("%s_%s", ns, key)
+}
+
+func stringToHeader(value string) map[string]string {
+	headersPairs := strings.Split(value, ",")
+	headers := make(map[string]string)
+
+	for _, header := range headersPairs {
+		nameValue := strings.SplitN(header, "=", 2)
+		if len(nameValue) < 2 {
+			global.Error(errors.New("missing '="), "parse headers", "input", nameValue)
+			continue
+		}
+		name, err := url.QueryUnescape(nameValue[0])
+		if err != nil {
+			global.Error(err, "escape header key", "key", nameValue[0])
+			continue
+		}
+		trimmedName := strings.TrimSpace(name)
+		value, err := url.QueryUnescape(nameValue[1])
+		if err != nil {
+			global.Error(err, "escape header value", "value", nameValue[1])
+			continue
+		}
+		trimmedValue := strings.TrimSpace(value)
+
+		headers[trimmedName] = trimmedValue
+	}
+
+	return headers
+}
+
+func createCertPool(certBytes []byte) (*x509.CertPool, error) {
+	cp := x509.NewCertPool()
+	if ok := cp.AppendCertsFromPEM(certBytes); !ok {
+		return nil, errors.New("failed to append certificate to the cert pool")
+	}
+	return cp, nil
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/internal/header.go

@@ -0,0 +1,24 @@
+// 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.
+
+// Package internal contains common functionality for all OTLP exporters.
+package internal // import "go.opentelemetry.io/otel/exporters/otlp/internal"
+
+import "go.opentelemetry.io/otel"
+
+// GetUserAgentHeader return an OTLP header value form "OTel OTLP Exporter Go/{{ .Version }}"
+// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#user-agent
+func GetUserAgentHeader() string {
+	return "OTel OTLP Exporter Go/" + otel.Version()
+}

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

@@ -0,0 +1,64 @@
+// 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.
+
+package internal // import "go.opentelemetry.io/otel/exporters/otlp/internal"
+
+import "fmt"
+
+// PartialSuccess represents the underlying error for all handling
+// OTLP partial success messages.  Use `errors.Is(err,
+// PartialSuccess{})` to test whether an error passed to the OTel
+// error handler belongs to this category.
+type PartialSuccess struct {
+	ErrorMessage  string
+	RejectedItems int64
+	RejectedKind  string
+}
+
+var _ error = PartialSuccess{}
+
+// Error implements the error interface.
+func (ps PartialSuccess) Error() string {
+	msg := ps.ErrorMessage
+	if msg == "" {
+		msg = "empty message"
+	}
+	return fmt.Sprintf("OTLP partial success: %s (%d %s rejected)", msg, ps.RejectedItems, ps.RejectedKind)
+}
+
+// Is supports the errors.Is() interface.
+func (ps PartialSuccess) Is(err error) bool {
+	_, ok := err.(PartialSuccess)
+	return ok
+}
+
+// TracePartialSuccessError returns an error describing a partial success
+// response for the trace signal.
+func TracePartialSuccessError(itemsRejected int64, errorMessage string) error {
+	return PartialSuccess{
+		ErrorMessage:  errorMessage,
+		RejectedItems: itemsRejected,
+		RejectedKind:  "spans",
+	}
+}
+
+// MetricPartialSuccessError returns an error describing a partial success
+// response for the metric signal.
+func MetricPartialSuccessError(itemsRejected int64, errorMessage string) error {
+	return PartialSuccess{
+		ErrorMessage:  errorMessage,
+		RejectedItems: itemsRejected,
+		RejectedKind:  "metric data points",
+	}
+}

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

@@ -0,0 +1,153 @@
+// 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.
+
+// Package retry provides request retry functionality that can perform
+// configurable exponential backoff for transient errors and honor any
+// explicit throttle responses received.
+package retry // import "go.opentelemetry.io/otel/exporters/otlp/internal/retry"
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/cenkalti/backoff/v4"
+)
+
+// DefaultConfig are the recommended defaults to use.
+var DefaultConfig = Config{
+	Enabled:         true,
+	InitialInterval: 5 * time.Second,
+	MaxInterval:     30 * time.Second,
+	MaxElapsedTime:  time.Minute,
+}
+
+// Config defines configuration for retrying batches in case of export failure
+// using an exponential backoff.
+type Config struct {
+	// Enabled indicates whether to not retry sending batches in case of
+	// export failure.
+	Enabled bool
+	// InitialInterval the time to wait after the first failure before
+	// retrying.
+	InitialInterval time.Duration
+	// MaxInterval is the upper bound on backoff interval. Once this value is
+	// reached the delay between consecutive retries will always be
+	// `MaxInterval`.
+	MaxInterval time.Duration
+	// MaxElapsedTime is the maximum amount of time (including retries) spent
+	// trying to send a request/batch.  Once this value is reached, the data
+	// is discarded.
+	MaxElapsedTime time.Duration
+}
+
+// RequestFunc wraps a request with retry logic.
+type RequestFunc func(context.Context, func(context.Context) error) error
+
+// EvaluateFunc returns if an error is retry-able and if an explicit throttle
+// duration should be honored that was included in the error.
+//
+// The function must return true if the error argument is retry-able,
+// otherwise it must return false for the first return parameter.
+//
+// The function must return a non-zero time.Duration if the error contains
+// explicit throttle duration that should be honored, otherwise it must return
+// a zero valued time.Duration.
+type EvaluateFunc func(error) (bool, time.Duration)
+
+// RequestFunc returns a RequestFunc using the evaluate function to determine
+// if requests can be retried and based on the exponential backoff
+// configuration of c.
+func (c Config) RequestFunc(evaluate EvaluateFunc) RequestFunc {
+	if !c.Enabled {
+		return func(ctx context.Context, fn func(context.Context) error) error {
+			return fn(ctx)
+		}
+	}
+
+	return func(ctx context.Context, fn func(context.Context) error) error {
+		// Do not use NewExponentialBackOff since it calls Reset and the code here
+		// must call Reset after changing the InitialInterval (this saves an
+		// unnecessary call to Now).
+		b := &backoff.ExponentialBackOff{
+			InitialInterval:     c.InitialInterval,
+			RandomizationFactor: backoff.DefaultRandomizationFactor,
+			Multiplier:          backoff.DefaultMultiplier,
+			MaxInterval:         c.MaxInterval,
+			MaxElapsedTime:      c.MaxElapsedTime,
+			Stop:                backoff.Stop,
+			Clock:               backoff.SystemClock,
+		}
+		b.Reset()
+
+		for {
+			err := fn(ctx)
+			if err == nil {
+				return nil
+			}
+
+			retryable, throttle := evaluate(err)
+			if !retryable {
+				return err
+			}
+
+			bOff := b.NextBackOff()
+			if bOff == backoff.Stop {
+				return fmt.Errorf("max retry time elapsed: %w", err)
+			}
+
+			// Wait for the greater of the backoff or throttle delay.
+			var delay time.Duration
+			if bOff > throttle {
+				delay = bOff
+			} else {
+				elapsed := b.GetElapsedTime()
+				if b.MaxElapsedTime != 0 && elapsed+throttle > b.MaxElapsedTime {
+					return fmt.Errorf("max retry time would elapse: %w", err)
+				}
+				delay = throttle
+			}
+
+			if ctxErr := waitFunc(ctx, delay); ctxErr != nil {
+				return fmt.Errorf("%w: %s", ctxErr, err)
+			}
+		}
+	}
+}
+
+// Allow override for testing.
+var waitFunc = wait
+
+// wait takes the caller's context, and the amount of time to wait.  It will
+// return nil if the timer fires before or at the same time as the context's
+// deadline.  This indicates that the call can be retried.
+func wait(ctx context.Context, delay time.Duration) error {
+	timer := time.NewTimer(delay)
+	defer timer.Stop()
+
+	select {
+	case <-ctx.Done():
+		// Handle the case where the timer and context deadline end
+		// simultaneously by prioritizing the timer expiration nil value
+		// response.
+		select {
+		case <-timer.C:
+		default:
+			return ctx.Err()
+		}
+	case <-timer.C:
+	}
+
+	return nil
+}

vendor/go.opentelemetry.io/otel/exporters/otlp/internal/wrappederror.go

@@ -0,0 +1,61 @@
+// 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.
+
+package internal // import "go.opentelemetry.io/otel/exporters/otlp/internal"
+
+// ErrorKind is used to identify the kind of export error
+// being wrapped.
+type ErrorKind int
+
+const (
+	// TracesExport indicates the error comes from the OTLP trace exporter.
+	TracesExport ErrorKind = iota
+)
+
+// prefix returns a prefix for the Error() string.
+func (k ErrorKind) prefix() string {
+	switch k {
+	case TracesExport:
+		return "traces export: "
+	default:
+		return "unknown: "
+	}
+}
+
+// wrappedExportError wraps an OTLP exporter error with the kind of
+// signal that produced it.
+type wrappedExportError struct {
+	wrap error
+	kind ErrorKind
+}
+
+// WrapTracesError wraps an error from the OTLP exporter for traces.
+func WrapTracesError(err error) error {
+	return wrappedExportError{
+		wrap: err,
+		kind: TracesExport,
+	}
+}
+
+var _ error = wrappedExportError{}
+
+// Error attaches a prefix corresponding to the kind of exporter.
+func (t wrappedExportError) Error() string {
+	return t.kind.prefix() + t.wrap.Error()
+}
+
+// Unwrap returns the wrapped error.
+func (t wrappedExportError) Unwrap() error {
+	return t.wrap
+}