feat(carrier): add URL carrier

carrier/go.mod

@@ -0,0 +1,7 @@
+module github.com/aereal/otel-propagators/carrier
+
+go 1.21.5
+
+require go.opentelemetry.io/otel v1.21.0
+
+require go.opentelemetry.io/otel/trace v1.21.0

carrier/go.sum

@@ -0,0 +1,20 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-logr/logr v1.3.0 h1:2y3SDp0ZXuc6/cjLSZ+Q3ir+QB9T/iG5yYRXqsagWSY=
+github.com/go-logr/logr v1.3.0/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+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 v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+go.opentelemetry.io/otel v1.21.0 h1:hzLeKBZEL7Okw2mGzZ0cc4k/A7Fta0uoPgaJCr8fsFc=
+go.opentelemetry.io/otel v1.21.0/go.mod h1:QZzNPQPm1zLX4gZK4cMi+71eaorMSGT3A4znnUvNNEo=
+go.opentelemetry.io/otel/metric v1.21.0 h1:tlYWfeo+Bocx5kLEloTjbcDwBuELRrIFxwdQ36PlJu4=
+go.opentelemetry.io/otel/metric v1.21.0/go.mod h1:o1p3CA8nNHW8j5yuQLdc1eeqEaPfzug24uvsyIEJRWM=
+go.opentelemetry.io/otel/trace v1.21.0 h1:WD9i5gzvoUPuXIXH24ZNBudiarZDKuekPqi/E8fpfLc=
+go.opentelemetry.io/otel/trace v1.21.0/go.mod h1:LGbsEB0f9LGjN+OZaQQ26sohbOmiMR+BaslueVtS/qQ=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

carrier/url_carrier.go

@@ -0,0 +1,43 @@
+package carrier
+
+import (
+	"net/url"
+	"sync"
+
+	"go.opentelemetry.io/otel/propagation"
+)
+
+// NewURLCarrier returns a carrier adapts url.URL to satisfy the propagation.TextMapCarrier interface.
+func NewURLCarrier(u *url.URL) propagation.TextMapCarrier {
+	return &urlCarrier{URL: u}
+}
+
+type urlCarrier struct {
+	*url.URL
+	sync.RWMutex
+}
+
+func (uc *urlCarrier) Get(key string) string {
+	uc.RLock()
+	defer uc.RUnlock()
+	return uc.Query().Get(key)
+}
+
+func (uc *urlCarrier) Set(key, value string) {
+	uc.Lock()
+	defer uc.Unlock()
+	qs := uc.Query()
+	qs.Set(key, value)
+	uc.RawQuery = qs.Encode()
+}
+
+func (uc *urlCarrier) Keys() []string {
+	uc.RLock()
+	defer uc.RUnlock()
+	qs := uc.Query()
+	keys := make([]string, 0, len(qs))
+	for k := range qs {
+		keys = append(keys, k)
+	}
+	return keys
+}

carrier/url_carrier_test.go

@@ -0,0 +1,84 @@
+package carrier_test
+
+import (
+	"context"
+	"net/url"
+	"testing"
+
+	"github.com/aereal/otel-propagators/carrier"
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+var (
+	traceID trace.TraceID
+	spanID  trace.SpanID
+)
+
+func init() {
+	var err error
+	traceID, err = trace.TraceIDFromHex(traceIDStr)
+	if err != nil {
+		panic(err)
+	}
+	spanID, err = trace.SpanIDFromHex(spanIDStr)
+	if err != nil {
+		panic(err)
+	}
+}
+
+const (
+	traceIDStr = "4bf92f3577b34da6a3ce929d0e0e4736"
+	spanIDStr  = "00f067aa0ba902b7"
+)
+
+func TestURLCarrier(t *testing.T) {
+	var prop propagation.TraceContext
+	t.Run("initial state", func(t *testing.T) {
+		testURL, err := url.Parse("http://test.example/")
+		if err != nil {
+			t.Fatal(err)
+		}
+		ctx := context.Background()
+		sc := trace.SpanContextFromContext(prop.Extract(ctx, carrier.NewURLCarrier(testURL)))
+		want := trace.NewSpanContext(trace.SpanContextConfig{})
+		if !sc.Equal(want) {
+			t.Errorf("extracted span context mismatch:\n\twant: %#v\n\tgot: %#v", want, sc)
+		}
+	})
+	t.Run("injected/not sampled", func(t *testing.T) {
+		testURL, err := url.Parse("http://test.example/?traceparent=00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-00")
+		if err != nil {
+			t.Fatal(err)
+		}
+		ctx := context.Background()
+		prop.Inject(ctx, carrier.NewURLCarrier(testURL))
+		sc := trace.SpanContextFromContext(prop.Extract(ctx, carrier.NewURLCarrier(testURL)))
+		want := trace.NewSpanContext(trace.SpanContextConfig{
+			TraceID: traceID,
+			SpanID:  spanID,
+			Remote:  true,
+		})
+		if !sc.Equal(want) {
+			t.Errorf("extracted span context mismatch:\n\twant: %#v\n\tgot: %#v", want, sc)
+		}
+	})
+	t.Run("injected/sampled", func(t *testing.T) {
+		testURL, err := url.Parse("http://test.example/?traceparent=00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01")
+		if err != nil {
+			t.Fatal(err)
+		}
+		ctx := context.Background()
+		prop.Inject(ctx, carrier.NewURLCarrier(testURL))
+		sc := trace.SpanContextFromContext(prop.Extract(ctx, carrier.NewURLCarrier(testURL)))
+		want := trace.NewSpanContext(trace.SpanContextConfig{
+			TraceID:    traceID,
+			SpanID:     spanID,
+			Remote:     true,
+			TraceFlags: trace.FlagsSampled,
+		})
+		if !sc.Equal(want) {
+			t.Errorf("extracted span context mismatch:\n\twant: %#v\n\tgot: %#v", want, sc)
+		}
+	})
+}