initial import

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

go.mod

@@ -0,0 +1,17 @@
+module go.unistack.org/micro-tracer-otel/v4
+
+go 1.20
+
+require (
+	go.opentelemetry.io/otel v1.16.0
+	go.opentelemetry.io/otel/sdk v1.16.0
+	go.opentelemetry.io/otel/trace v1.16.0
+	go.unistack.org/micro/v4 v4.0.4
+)
+
+require (
+	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	go.opentelemetry.io/otel/metric v1.16.0 // indirect
+	golang.org/x/sys v0.9.0 // indirect
+)

go.sum

@@ -0,0 +1,26 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.2.4 h1:g01GSCwiDw2xSZfjJ2/T9M+S6pFdcNtFYsp+Y43HYDQ=
+github.com/go-logr/logr v1.2.4/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/stretchr/testify v1.8.3 h1:RP3t2pwF7cMEbC1dqtB6poj3niw/9gnV4Cjg5oW5gtY=
+go.opentelemetry.io/otel v1.16.0 h1:Z7GVAX/UkAXPKsy94IU+i6thsQS4nb7LviLpnaNeW8s=
+go.opentelemetry.io/otel v1.16.0/go.mod h1:vl0h9NUa1D5s1nv3A5vZOYWn8av4K8Ml6JDeHrT/bx4=
+go.opentelemetry.io/otel/metric v1.16.0 h1:RbrpwVG1Hfv85LgnZ7+txXioPDoh6EdbZHo26Q3hqOo=
+go.opentelemetry.io/otel/metric v1.16.0/go.mod h1:QE47cpOmkwipPiefDwo2wDzwJrlfxxNYodqc4xnGCo4=
+go.opentelemetry.io/otel/sdk v1.16.0 h1:Z1Ok1YsijYL0CSJpHt4cS3wDDh7p572grzNrBMiMWgE=
+go.opentelemetry.io/otel/sdk v1.16.0/go.mod h1:tMsIuKXuuIWPBAOrH+eHtvhTL+SntFtXF9QD68aP6p4=
+go.opentelemetry.io/otel/trace v1.16.0 h1:8JRpaObFoW0pxuVPapkgH8UhHQj+bJW8jJsCZEu5MQs=
+go.opentelemetry.io/otel/trace v1.16.0/go.mod h1:Yt9vYq1SdNz3xdjZZK7wcXv1qv2pwLkqr2QVwea0ef0=
+go.unistack.org/micro/v4 v4.0.1 h1:xo1IxbVfgh8i0eY0VeYa3cbb13u5n/Mxnp3FOgWD4Jo=
+go.unistack.org/micro/v4 v4.0.1/go.mod h1:p/J5UcSJjfHsWGT31uKoghQ5rUQZzQJBAFy+Z4+ZVMs=
+go.unistack.org/micro/v4 v4.0.4 h1:tbCpqXQTAqK57LeasRR1uSTnGC+xs7K57bxifKmhzUQ=
+go.unistack.org/micro/v4 v4.0.4/go.mod h1:+wBa98rSf+mRXb/MuSVFPXtDrqN0k8rzPQiC8wRCwCo=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.9.0 h1:KS/R3tvhPqvJvwcKfnBHJwwthS11LRhmM5D59eEXa0s=
+golang.org/x/sys v0.9.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

options.go

@@ -0,0 +1,25 @@
+package otel
+
+import (
+	tracesdk "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+	"go.unistack.org/micro/v4/tracer"
+)
+
+type providerKey struct{}
+
+func Provider(opts ...tracesdk.TracerProvider) tracer.Option {
+	return tracer.SetOption(providerKey{}, opts)
+}
+
+type providerOptionsKey struct{}
+
+func ProviderOptions(opts ...tracesdk.TracerProviderOption) tracer.Option {
+	return tracer.SetOption(providerOptionsKey{}, opts)
+}
+
+type tracerOptionsKey struct{}
+
+func TracerOptions(opts ...trace.TracerOption) tracer.Option {
+	return tracer.SetOption(tracerOptionsKey{}, opts)
+}

otel.go

@@ -0,0 +1,284 @@
+package otel
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/baggage"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/propagation"
+	tracesdk "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/trace"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/tracer"
+)
+
+var _ tracer.Tracer = (*otelTracer)(nil)
+
+type otelTracer struct {
+	opts       tracer.Options
+	tracep     *tracesdk.TracerProvider
+	tracer     trace.Tracer
+	propagator propagation.TextMapPropagator
+}
+
+type otelSpan struct {
+	ctx       context.Context
+	tracer    trace.Tracer
+	tracep    *tracesdk.TracerProvider
+	span      trace.Span
+	opts      tracer.SpanOptions
+	status    tracer.SpanStatus
+	statusMsg string
+}
+
+func (ot *otelTracer) Name() string {
+	return ot.opts.Name
+}
+
+func (ot *otelTracer) Flush(ctx context.Context) error {
+	return ot.tracep.ForceFlush(ctx)
+}
+
+func (ot *otelTracer) Init(opts ...tracer.Option) error {
+	for _, o := range opts {
+		o(&ot.opts)
+	}
+
+	var to []trace.TracerOption
+	if o, ok := ot.opts.Context.Value(tracerOptionsKey{}).([]trace.TracerOption); ok {
+		to = o
+	}
+
+	var tp *tracesdk.TracerProvider
+	if p, ok := ot.opts.Context.Value(providerKey{}).(*tracesdk.TracerProvider); ok {
+		tp = p
+	}
+
+	if o, ok := ot.opts.Context.Value(providerOptionsKey{}).([]tracesdk.TracerProviderOption); ok {
+		tp = tracesdk.NewTracerProvider(o...)
+	}
+
+	if tp == nil {
+		return fmt.Errorf("missing Provider or ProviderOptions option")
+	}
+
+	ot.tracep = tp
+	ot.tracer = tp.Tracer(ot.opts.Name, to...)
+	ot.propagator = propagation.NewCompositeTextMapPropagator(
+		propagation.Baggage{},
+		propagation.TraceContext{},
+	)
+
+	return nil
+}
+
+func (ot *otelTracer) Start(ctx context.Context, name string, opts ...tracer.SpanOption) (context.Context, tracer.Span) {
+	options := tracer.NewSpanOptions(opts...)
+	var span trace.Span
+	switch options.Kind {
+	case tracer.SpanKindInternal, tracer.SpanKindUnspecified:
+		ctx, span = ot.startSpanFromContext(ctx, name)
+	case tracer.SpanKindClient, tracer.SpanKindProducer:
+		ctx, span = ot.startSpanFromOutgoingContext(ctx, name)
+	case tracer.SpanKindServer, tracer.SpanKindConsumer:
+		ctx, span = ot.startSpanFromIncomingContext(ctx, name)
+	}
+	return ctx, &otelSpan{ctx: ctx, tracep: ot.tracep, tracer: ot.tracer, span: span, opts: options}
+}
+
+func (os *otelSpan) SetStatus(st tracer.SpanStatus, msg string) {
+	switch st {
+	case tracer.SpanStatusError:
+		os.span.SetStatus(codes.Error, msg)
+		os.span.RecordError(errors.New(msg))
+	case tracer.SpanStatusOK:
+		os.span.SetStatus(codes.Ok, msg)
+	case tracer.SpanStatusUnset:
+		os.span.SetStatus(codes.Unset, msg)
+	}
+	os.status = st
+	os.statusMsg = msg
+}
+
+func (os *otelSpan) Status() (tracer.SpanStatus, string) {
+	return os.status, os.statusMsg
+}
+
+func (os *otelSpan) Tracer() tracer.Tracer {
+	return &otelTracer{tracep: os.tracep, tracer: os.tracer}
+}
+
+func (os *otelSpan) Finish(opts ...tracer.SpanOption) {
+	if len(os.opts.Labels) > 0 {
+		os.span.SetAttributes(convertLabels(os.opts.Labels...)...)
+	}
+	os.span.End()
+}
+
+func (os *otelSpan) AddEvent(name string, opts ...tracer.EventOption) {
+	os.span.AddEvent(name)
+}
+
+func (os *otelSpan) Context() context.Context {
+	return trace.ContextWithSpan(os.ctx, os.span)
+}
+
+func (os *otelSpan) SetName(name string) {
+	os.span.SetName(name)
+}
+
+func (os *otelSpan) SetLabels(labels ...interface{}) {
+	os.opts.Labels = labels
+}
+
+func (os *otelSpan) Kind() tracer.SpanKind {
+	return os.opts.Kind
+}
+
+func (os *otelSpan) AddLabels(labels ...interface{}) {
+	os.opts.Labels = append(os.opts.Labels, labels...)
+}
+
+func NewTracer(opts ...tracer.Option) *otelTracer {
+	options := tracer.NewOptions(opts...)
+	return &otelTracer{opts: options}
+}
+
+func (ot *otelTracer) startSpanFromContext(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	md, ok := metadata.FromContext(ctx)
+	if !ok {
+		md = metadata.New(1)
+	}
+
+	mc := make(propagation.MapCarrier)
+	for k, v := range md {
+		for _, f := range ot.propagator.Fields() {
+			if strings.EqualFold(k, f) {
+				mc[f] = v
+			}
+		}
+	}
+
+	ctx = ot.propagator.Extract(ctx, mc)
+	spanCtx := trace.SpanContextFromContext(ctx)
+	ctx = baggage.ContextWithBaggage(ctx, baggage.FromContext(ctx))
+
+	var span trace.Span
+	ctx, span = ot.tracer.Start(trace.ContextWithRemoteSpanContext(ctx, spanCtx), name, opts...)
+
+	mc = make(propagation.MapCarrier)
+	ot.propagator.Inject(ctx, mc)
+	for k, v := range mc {
+		md.Set(k, v)
+	}
+	ctx = metadata.NewContext(ctx, md)
+
+	return ctx, span
+}
+
+func (ot *otelTracer) startSpanFromOutgoingContext(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	md, ok := metadata.FromOutgoingContext(ctx)
+	if !ok {
+		md = metadata.New(1)
+	}
+
+	mc := make(propagation.MapCarrier)
+	for k, v := range md {
+		for _, f := range ot.propagator.Fields() {
+			if strings.EqualFold(k, f) {
+				mc[f] = v
+			}
+		}
+	}
+
+	ctx = ot.propagator.Extract(ctx, mc)
+	spanCtx := trace.SpanContextFromContext(ctx)
+	ctx = baggage.ContextWithBaggage(ctx, baggage.FromContext(ctx))
+
+	var span trace.Span
+	ctx, span = ot.tracer.Start(trace.ContextWithRemoteSpanContext(ctx, spanCtx), name, opts...)
+
+	mc = make(propagation.MapCarrier)
+	ot.propagator.Inject(ctx, mc)
+	for k, v := range mc {
+		md.Set(k, v)
+	}
+	ctx = metadata.NewOutgoingContext(ctx, md)
+
+	return ctx, span
+}
+
+func (ot *otelTracer) startSpanFromIncomingContext(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		md = metadata.New(1)
+	}
+
+	mc := make(propagation.MapCarrier)
+	for k, v := range md {
+		for _, f := range ot.propagator.Fields() {
+			if strings.EqualFold(k, f) {
+				mc[f] = v
+			}
+		}
+	}
+
+	ctx = ot.propagator.Extract(ctx, mc)
+	spanCtx := trace.SpanContextFromContext(ctx)
+	ctx = baggage.ContextWithBaggage(ctx, baggage.FromContext(ctx))
+
+	var span trace.Span
+	ctx, span = ot.tracer.Start(trace.ContextWithRemoteSpanContext(ctx, spanCtx), name, opts...)
+
+	mc = make(propagation.MapCarrier)
+	ot.propagator.Inject(ctx, mc)
+	for k, v := range mc {
+		md.Set(k, v)
+	}
+	ctx = metadata.NewIncomingContext(ctx, md)
+
+	return ctx, span
+}
+
+func convertLabels(labels ...interface{}) []attribute.KeyValue {
+	kv := make([]attribute.KeyValue, 0, len(labels)/2)
+	for idx := 0; idx < len(labels)/2; idx += 2 {
+		if v, ok := labels[idx].(attribute.KeyValue); ok {
+			kv = append(kv, v)
+		}
+		switch v := labels[idx+1].(type) {
+		case attribute.KeyValue:
+			kv = append(kv, v)
+		case bool:
+			kv = append(kv, attribute.Bool(labels[idx].(string), v))
+		case []bool:
+			kv = append(kv, attribute.BoolSlice(labels[idx].(string), v))
+		case float64:
+			kv = append(kv, attribute.Float64(labels[idx].(string), v))
+		case []float64:
+			kv = append(kv, attribute.Float64Slice(labels[idx].(string), v))
+		case int:
+			kv = append(kv, attribute.Int(labels[idx].(string), v))
+		case []int:
+			kv = append(kv, attribute.IntSlice(labels[idx].(string), v))
+		case int64:
+			kv = append(kv, attribute.Int64(labels[idx].(string), v))
+		case []int64:
+			kv = append(kv, attribute.Int64Slice(labels[idx].(string), v))
+		case string:
+			kv = append(kv, attribute.String(labels[idx].(string), v))
+		case []string:
+			kv = append(kv, attribute.StringSlice(labels[idx].(string), v))
+		case fmt.Stringer:
+			kv = append(kv, attribute.Stringer(labels[idx].(string), v))
+		default:
+			kv = append(kv, attribute.String(labels[idx].(string), fmt.Sprintf("%v", v)))
+		}
+	}
+
+	return kv
+}