NewOTelFromEnv is a convenience function to allow OpenTelemetry tracing configuration via environment variables. Refer to official OTel SDK configuration docs to see the available options. https://opentelemetry.io/docs/languages/sdk-configuration/general/
(serviceName string, logger log.Logger, opts ...OTelOption)
| 35 | // Refer to official OTel SDK configuration docs to see the available options. |
| 36 | // https://opentelemetry.io/docs/languages/sdk-configuration/general/ |
| 37 | func NewOTelFromEnv(serviceName string, logger log.Logger, opts ...OTelOption) (io.Closer, error) { |
| 38 | if os.Getenv("OTEL_TRACES_EXPORTER") == "" && os.Getenv("OTEL_EXPORTER_OTLP_ENDPOINT") == "" && os.Getenv("OTEL_EXPORTER_OTLP_TRACES_ENDPOINT") == "" { |
| 39 | // No tracing is configured, so don't initialize the tracer as it would complain on every span about localhost:4718 not accepting traces. |
| 40 | return ioCloser(func() error { return nil }), nil |
| 41 | } |
| 42 | |
| 43 | level.Info(logger).Log("msg", "initialising OpenTelemetry tracer") |
| 44 | |
| 45 | exp, err := autoexport.NewSpanExporter(context.Background()) |
| 46 | if err != nil { |
| 47 | return nil, fmt.Errorf("failed to create OTEL exporter: %w", err) |
| 48 | } |
| 49 | |
| 50 | var cfg config |
| 51 | for _, opt := range opts { |
| 52 | opt.apply(&cfg) |
| 53 | } |
| 54 | |
| 55 | resource, err := NewResource(serviceName, cfg.resourceAttributes) |
| 56 | if err != nil { |
| 57 | return nil, fmt.Errorf("failed to initialise trace resource: %w", err) |
| 58 | } |
| 59 | |
| 60 | options := []tracesdk.TracerProviderOption{ |
| 61 | tracesdk.WithBatcher(exp), |
| 62 | tracesdk.WithResource(resource), |
| 63 | } |
| 64 | if jaegerRemoteSampler, ok, err := maybeJaegerRemoteSamplerFromEnv(serviceName); err != nil { |
| 65 | return nil, fmt.Errorf("failed to create Jaeger remote sampler: %w", err) |
| 66 | } else if ok { |
| 67 | options = append(options, tracesdk.WithSampler(&JaegerDebuggingSampler{jaegerRemoteSampler})) |
| 68 | } else { |
| 69 | options = append(options, tracesdk.WithSampler(&JaegerDebuggingSampler{otelSamplerFromEnv()})) |
| 70 | } |
| 71 | options = append(options, cfg.tracerProviderOptions...) |
| 72 | |
| 73 | level.Debug(logger).Log("msg", "OpenTelemetry tracer provider initialized from OTel environment variables") |
| 74 | tpsdk := tracesdk.NewTracerProvider(options...) |
| 75 | tp := trace.TracerProvider(tpsdk) |
| 76 | if !cfg.pyroscopeDisabled { |
| 77 | tp = otelpyroscope.NewTracerProvider(tp) |
| 78 | } |
| 79 | |
| 80 | otel.SetTracerProvider(tp) |
| 81 | otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(OTelPropagatorsFromEnv()...)) |
| 82 | otel.SetErrorHandler(otelErrorHandlerFunc(func(err error) { |
| 83 | level.Error(logger).Log("msg", "OpenTelemetry.ErrorHandler", "err", err) |
| 84 | })) |
| 85 | |
| 86 | return ioCloser(func() error { |
| 87 | ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second) |
| 88 | defer cancel() |
| 89 | if err := tpsdk.Shutdown(ctx); err != nil { |
| 90 | level.Error(logger).Log("msg", "OpenTelemetry trace provider failed to shutdown", "err", err) |
| 91 | return err |
| 92 | } |
| 93 | return nil |
| 94 | }), nil |