src: revert golobal dialer (#716)

Signed-off-by: Matej Vasek <mvasek@redhat.com>

cloudevents/emitter.go

@@ -3,6 +3,7 @@ package cloudevents
 import (
 	"context"
 	"fmt"
+	nethttp "net/http"
 
 	cloudevents "github.com/cloudevents/sdk-go/v2"
 	"github.com/cloudevents/sdk-go/v2/client"
@@ -24,6 +25,7 @@ type Emitter struct {
 	Id          string
 	Data        string
 	ContentType string
+	Transport   nethttp.RoundTripper
 }
 
 func NewEmitter() *Emitter {
@@ -33,14 +35,21 @@ func NewEmitter() *Emitter {
 		Id:          uuid.NewString(),
 		Data:        "",
 		ContentType: event.TextPlain,
+		Transport:   nethttp.DefaultTransport,
 	}
 }
 
 func (e *Emitter) Emit(ctx context.Context, endpoint string) (err error) {
-	c, err := newClient(endpoint)
+	p, err := http.New(http.WithTarget(endpoint), http.WithRoundTripper(e.Transport))
 	if err != nil {
-		return
+		return err
 	}
+
+	c, err := client.New(p)
+	if err != nil {
+		return err
+	}
+
 	evt := event.Event{
 		Context: event.EventContextV1{
 			Type:   e.Type,
@@ -60,11 +69,3 @@ func (e *Emitter) Emit(ctx context.Context, endpoint string) (err error) {
 	}
 	return nil
 }
-
-func newClient(target string) (c client.Client, err error) {
-	p, err := http.New(http.WithTarget(target))
-	if err != nil {
-		return
-	}
-	return client.New(p)
-}

cmd/emit.go

@@ -4,12 +4,14 @@ import (
 	"context"
 	"errors"
 	"io/ioutil"
+	"net/http"
 
 	"github.com/google/uuid"
 	"github.com/ory/viper"
 	"github.com/spf13/cobra"
 	fn "knative.dev/kn-plugin-func"
 	"knative.dev/kn-plugin-func/cloudevents"
+	fnhttp "knative.dev/kn-plugin-func/http"
 	"knative.dev/kn-plugin-func/knative"
 )
 
@@ -25,6 +27,9 @@ func newEmitClient(cfg emitConfig) (*fn.Client, error) {
 	e.Type = cfg.Type
 	e.ContentType = cfg.ContentType
 	e.Data = cfg.Data
+	if e.Transport != nil {
+		e.Transport = cfg.Transport
+	}
 	if cfg.File != "" {
 		// See config.Validate for --Data and --file exclusivity enforcement
 		b, err := ioutil.ReadFile(cfg.File)
@@ -106,6 +111,9 @@ func runEmit(cmd *cobra.Command, _ []string, clientFn emitClientFn) (err error)
 	}
 
 	// Instantiate a client based on the final value of config
+	transport := fnhttp.NewRoundTripper()
+	defer transport.Close()
+	config.Transport = transport
 	client, err := clientFn(config)
 	if err != nil {
 		return err
@@ -175,6 +183,7 @@ type emitConfig struct {
 	ContentType string
 	Sink        string
 	Verbose     bool
+	Transport   http.RoundTripper
 }
 
 func newEmitConfig() emitConfig {

cmd/func/main.go

@@ -2,13 +2,10 @@ package main
 
 import (
 	"context"
-	"net/http"
 	"os"
 	"os/signal"
 	"syscall"
 
-	funcHttp "knative.dev/kn-plugin-func/http"
-
 	"knative.dev/kn-plugin-func/cmd"
 )
 
@@ -17,11 +14,6 @@ import (
 var date, vers, hash string
 
 func main() {
-
-	rt := funcHttp.NewRoundTripper()
-	http.DefaultTransport = rt
-	defer rt.Close()
-
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()