Update CE clients.

cmd/sendevent/main.go

@@ -26,8 +26,9 @@ import (
 	"os"
 
 	cloudevents "github.com/cloudevents/sdk-go/v2"
-
+	"go.opencensus.io/plugin/ochttp"
 	"knative.dev/eventing/pkg/utils"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 )
 
 var (
@@ -64,7 +65,11 @@ func main() {
 		source = fmt.Sprintf("http://%s", utils.GetClusterDomainName())
 	}
 
-	t, err := cloudevents.NewHTTP(cloudevents.WithTarget(target))
+	t, err := cloudevents.NewHTTP(
+		cloudevents.WithTarget(target),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	if err != nil {
 		log.Printf("failed to create transport, %v", err)
 		os.Exit(1)

pkg/adapter/v2/cloudevents.go

@@ -21,6 +21,9 @@ import (
 	"fmt"
 	"net/url"
 
+	"go.opencensus.io/plugin/ochttp"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
+
 	cloudevents "github.com/cloudevents/sdk-go/v2"
 	"github.com/cloudevents/sdk-go/v2/event"
 	"github.com/cloudevents/sdk-go/v2/protocol"
@@ -36,6 +39,9 @@ func NewCloudEventsClient(target string, ceOverrides *duckv1.CloudEventOverrides
 	if len(target) > 0 {
 		pOpts = append(pOpts, cloudevents.WithTarget(target))
 	}
+	pOpts = append(pOpts, cloudevents.WithRoundTripper(&ochttp.Transport{
+		Propagation: tracecontextb3.TraceContextEgress,
+	}))
 
 	p, err := cloudevents.NewHTTP(pOpts...)
 	if err != nil {

pkg/channel/message_receiver_test.go

@@ -21,6 +21,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"go.opencensus.io/plugin/ochttp"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 	nethttp "net/http"
 	"net/http/httptest"
 	"testing"
@@ -220,6 +222,9 @@ func TestMessageReceiver_ServerStart_trace_propagation(t *testing.T) {
 	p, err := cloudevents.NewHTTP(
 		http.WithTarget(server.URL),
 		http.WithMethod(method),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	)
 	require.NoError(t, err)
 	p.RequestTemplate.Host = host

test/performance/infra/sender/http_load_generator.go

@@ -19,6 +19,8 @@ package sender
 import (
 	"context"
 	"fmt"
+	"go.opencensus.io/plugin/ochttp"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 	"math/rand"
 	"net"
 	"net/http"
@@ -188,6 +190,9 @@ func vegetaAttackerTransport() *http.Transport {
 func newCloudEventsClient(sinkUrl string) (cloudevents.Client, error) {
 	t, err := cloudevents.NewHTTP(
 		cloudevents.WithTarget(sinkUrl),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create transport: %v", err)

test/test_images/heartbeats/main.go

@@ -26,10 +26,11 @@ import (
 	"strconv"
 	"time"
 
-	duckv1 "knative.dev/pkg/apis/duck/v1"
-
 	cloudevents "github.com/cloudevents/sdk-go/v2"
 	"github.com/kelseyhightower/envconfig"
+	"go.opencensus.io/plugin/ochttp"
+	duckv1 "knative.dev/pkg/apis/duck/v1"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 )
 
 type Heartbeat struct {
@@ -89,7 +90,11 @@ func main() {
 		ceOverrides = &overrides
 	}
 
-	p, err := cloudevents.NewHTTP(cloudevents.WithTarget(sink))
+	p, err := cloudevents.NewHTTP(
+		cloudevents.WithTarget(sink),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	if err != nil {
 		log.Fatalf("failed to create protocol: %s", err.Error())
 	}

test/test_images/sequencestepper/main.go

@@ -23,6 +23,8 @@ import (
 	"log"
 
 	cloudevents "github.com/cloudevents/sdk-go/v2"
+	"go.opencensus.io/plugin/ochttp"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 )
 
 var (
@@ -61,7 +63,11 @@ func main() {
 	// parse the command line flags
 	flag.Parse()
 
-	t, err := cloudevents.NewHTTP(cloudevents.WithPort(8080))
+	t, err := cloudevents.NewHTTP(
+		cloudevents.WithPort(8080),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	if err != nil {
 		log.Fatalf("failed to create transport, %v", err)
 	}

test/test_images/transformevents/main.go

@@ -22,9 +22,10 @@ import (
 	"log"
 
 	cloudevents "github.com/cloudevents/sdk-go/v2"
+	"go.opencensus.io/plugin/ochttp"
 	"go.uber.org/zap"
-
 	"knative.dev/eventing/pkg/tracing"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 )
 
 var (
@@ -72,7 +73,11 @@ func main() {
 		log.Fatalf("Unable to setup trace publishing: %v", err)
 	}
 
-	t, err := cloudevents.NewHTTP(cloudevents.WithPort(8080))
+	t, err := cloudevents.NewHTTP(
+		cloudevents.WithPort(8080),
+		cloudevents.WithRoundTripper(&ochttp.Transport{
+			Propagation: tracecontextb3.TraceContextEgress,
+		}))
 	if err != nil {
 		log.Fatalf("failed to create transport, %v", err)
 	}

test/upgrade/prober/wathola/client/receiver.go

@@ -23,7 +23,9 @@ import (
 	cloudevents "github.com/cloudevents/sdk-go/v2"
 	cloudeventshttp "github.com/cloudevents/sdk-go/v2/protocol/http"
 	"github.com/wavesoftware/go-ensure"
+	"go.opencensus.io/plugin/ochttp"
 	"knative.dev/eventing/test/upgrade/prober/wathola/config"
+	"knative.dev/pkg/tracing/propagation/tracecontextb3"
 )
 
 var log = config.Log
@@ -38,9 +40,11 @@ func Receive(
 	receiveEvent ReceiveEvent,
 	middlewares ...cloudeventshttp.Middleware,
 ) {
-	portOpt := cloudevents.WithPort(port)
 	opts := make([]cloudeventshttp.Option, 0)
-	opts = append(opts, portOpt)
+	opts = append(opts, cloudevents.WithPort(port))
+	opts = append(opts, cloudevents.WithRoundTripper(&ochttp.Transport{
+		Propagation: tracecontextb3.TraceContextEgress,
+	}))
 	if config.Instance.Readiness.Enabled {
 		readyOpt := cloudevents.WithMiddleware(readinessMiddleware)
 		opts = append(opts, readyOpt)