[connectrpc#477] add WithProtoJSONOptions() expose protojson marshall…

…ing options

codec.go

@@ -120,7 +120,9 @@ func (c *protoBinaryCodec) IsBinary() bool {
 }
 
 type protoJSONCodec struct {
-	name string
+	name             string
+	marshalOptions   protojson.MarshalOptions
+	unmarshalOptions protojson.UnmarshalOptions
 }
 
 var _ Codec = (*protoJSONCodec)(nil)
@@ -132,8 +134,7 @@ func (c *protoJSONCodec) Marshal(message any) ([]byte, error) {
 	if !ok {
 		return nil, errNotProto(message)
 	}
-	var options protojson.MarshalOptions
-	return options.Marshal(protoMessage)
+	return c.marshalOptions.Marshal(protoMessage)
 }
 
 func (c *protoJSONCodec) Unmarshal(binary []byte, message any) error {
@@ -144,8 +145,7 @@ func (c *protoJSONCodec) Unmarshal(binary []byte, message any) error {
 	if len(binary) == 0 {
 		return errors.New("zero-length payload is not a valid JSON object")
 	}
-	var options protojson.UnmarshalOptions
-	return options.Unmarshal(binary, protoMessage)
+	return c.unmarshalOptions.Unmarshal(binary, protoMessage)
 }
 
 func (c *protoJSONCodec) MarshalStable(message any) ([]byte, error) {

codec_test.go

@@ -22,7 +22,9 @@ import (
 
 	"github.com/bufbuild/connect-go/internal/assert"
 	pingv1 "github.com/bufbuild/connect-go/internal/gen/connect/ping/v1"
+	"google.golang.org/protobuf/encoding/protojson"
 	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/apipb"
 	"google.golang.org/protobuf/types/known/emptypb"
 	"google.golang.org/protobuf/types/known/structpb"
 )
@@ -110,3 +112,59 @@ func TestJSONCodec(t *testing.T) {
 		assert.Sprintf(`error message should explain that "" is not a valid JSON object`),
 	)
 }
+
+func TestJSONCodecWithOptions(t *testing.T) {
+	t.Parallel()
+
+	codec := &protoJSONCodec{
+		name: "json",
+		marshalOptions: protojson.MarshalOptions{
+			Multiline:       true,
+			Indent:          "  ",
+			UseProtoNames:   true,
+			UseEnumNumbers:  true,
+			EmitUnpopulated: true,
+		},
+		unmarshalOptions: protojson.UnmarshalOptions{
+			AllowPartial:   false,
+			DiscardUnknown: true,
+			Resolver:       nil,
+		},
+	}
+
+	in := apipb.Api{
+		Name:    "api",
+		Version: "1.0",
+	}
+	data, err := codec.Marshal(&in)
+	if err != nil {
+		t.Error(err)
+	}
+
+	out := apipb.Api{}
+	err = codec.Unmarshal(data, &out)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if out.Name != "api" || out.Version != "1.0" {
+		t.Error("values not preserved after round trip through marshal and unmarshal")
+	}
+
+	asJSON := string(data)
+	lines := strings.Count(asJSON, "\n")
+	spaces := strings.Count(asJSON, " ")
+
+	if lines == 0 || spaces == 0 {
+		t.Error("expected formatted JSON")
+	}
+
+	if !strings.Contains(asJSON, "\"source_context\"") {
+		t.Error("expected unpopulated fields to be included in message")
+	}
+
+	err = codec.Unmarshal([]byte(`{"name": "api", "foo": "bar"}`), &out)
+	if err != nil {
+		t.Error("expected unknown fields to be ignored, got error:", err)
+	}
+}

option.go

@@ -19,6 +19,8 @@ import (
 	"context"
 	"io"
 	"net/http"
+
+	"google.golang.org/protobuf/encoding/protojson"
 )
 
 // A ClientOption configures a [Client].
@@ -77,7 +79,20 @@ func WithGRPCWeb() ClientOption {
 // lowerCamelCase, zero values are omitted, missing required fields are errors,
 // enums are emitted as strings, etc.
 func WithProtoJSON() ClientOption {
-	return WithCodec(&protoJSONCodec{codecNameJSON})
+	return WithCodec(&protoJSONCodec{name: codecNameJSON})
+}
+
+// WithProtoJSONOptions is identical to WithProtoJSON, but also allows
+// protojson marshalling options to be configured.
+func WithProtoJSONOptions(
+	marshalOptions protojson.MarshalOptions,
+	unmarshalOptions protojson.UnmarshalOptions,
+) ClientOption {
+	return WithCodec(&protoJSONCodec{
+		name:             codecNameJSON,
+		marshalOptions:   marshalOptions,
+		unmarshalOptions: unmarshalOptions,
+	})
 }
 
 // WithSendCompression configures the client to use the specified algorithm to
@@ -553,7 +568,7 @@ func withProtoBinaryCodec() Option {
 
 func withProtoJSONCodecs() HandlerOption {
 	return WithHandlerOptions(
-		WithCodec(&protoJSONCodec{codecNameJSON}),
-		WithCodec(&protoJSONCodec{codecNameJSONCharsetUTF8}),
+		WithCodec(&protoJSONCodec{name: codecNameJSON}),
+		WithCodec(&protoJSONCodec{name: codecNameJSONCharsetUTF8}),
 	)
 }