[v3] remove using global map for default codecs (#224)

* remove using global map for default codecs

* fix tests

client/noop.go

@@ -17,11 +17,6 @@ import (
 	"go.unistack.org/micro/v3/tracer"
 )
 
-// DefaultCodecs will be used to encode/decode data
-var DefaultCodecs = map[string]codec.Codec{
-	"application/octet-stream": codec.NewCodec(),
-}
-
 type noopClient struct {
 	funcPublish      FuncPublish
 	funcBatchPublish FuncBatchPublish
@@ -178,9 +173,6 @@ func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
 	if cf, ok := n.opts.Codecs[contentType]; ok {
 		return cf, nil
 	}
-	if cf, ok := DefaultCodecs[contentType]; ok {
-		return cf, nil
-	}
 	return nil, codec.ErrUnknownContentType
 }
 

client/noop_test.go

@@ -3,6 +3,8 @@ package client
 import (
 	"context"
 	"testing"
+
+	"go.unistack.org/micro/v3/codec"
 )
 
 type testHook struct {
@@ -19,7 +21,7 @@ func (t *testHook) Publish(fn FuncPublish) FuncPublish {
 func TestNoopHook(t *testing.T) {
 	h := &testHook{}
 
-	c := NewClient(Hooks(HookPublish(h.Publish)))
+	c := NewClient(Codec("application/octet-stream", codec.NewCodec()), Hooks(HookPublish(h.Publish)))
 
 	if err := c.Init(); err != nil {
 		t.Fatal(err)

client/options.go

@@ -198,7 +198,7 @@ func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
-		Codecs:      DefaultCodecs,
+		Codecs:      make(map[string]codec.Codec),
 		CallOptions: CallOptions{
 			Context:        context.Background(),
 			Backoff:        DefaultBackoff,