Add details to stream error response

Makefile

@@ -5,7 +5,9 @@
 
 PKG=github.com/grpc-ecosystem/grpc-gateway
 GO_PLUGIN=bin/protoc-gen-go
-GO_PLUGIN_PKG=github.com/golang/protobuf/protoc-gen-go
+GO_PROTOBUF_REPO=github.com/golang/protobuf
+GO_PLUGIN_PKG=$(GO_PROTOBUF_REPO)/protoc-gen-go
+GO_PTYPES_ANY_PKG=$(GO_PROTOBUF_REPO)/ptypes/any
 SWAGGER_PLUGIN=bin/protoc-gen-swagger
 SWAGGER_PLUGIN_SRC= utilities/doc.go \
 		    utilities/pattern.go \
@@ -91,7 +93,7 @@ $(GO_PLUGIN):
 	go build -o $@ $(GO_PLUGIN_PKG)
 
 $(RUNTIME_GO): $(RUNTIME_PROTO) $(GO_PLUGIN)
-	protoc -I $(PROTOC_INC_PATH) --plugin=$(GO_PLUGIN) -I. --go_out=$(PKGMAP):. $(RUNTIME_PROTO)
+	protoc -I $(PROTOC_INC_PATH) --plugin=$(GO_PLUGIN) -I $(GOPATH)/src/$(GO_PTYPES_ANY_PKG) -I. --go_out=$(PKGMAP):. $(RUNTIME_PROTO)
 
 $(OPENAPIV2_GO): $(OPENAPIV2_PROTO) $(GO_PLUGIN)
 	protoc -I $(PROTOC_INC_PATH) --plugin=$(GO_PLUGIN) -I. --go_out=$(PKGMAP):$(GOPATH)/src $(OPENAPIV2_PROTO)

runtime/handler.go

@@ -7,6 +7,7 @@ import (
 	"net/textproto"
 
 	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/ptypes/any"
 	"github.com/grpc-ecosystem/grpc-gateway/runtime/internal"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
@@ -42,7 +43,7 @@ func ForwardResponseStream(ctx context.Context, mux *ServeMux, marshaler Marshal
 	if d, ok := marshaler.(Delimited); ok {
 		delimiter = d.Delimiter()
 	} else {
-	    delimiter = []byte("\n")
+		delimiter = []byte("\n")
 	}
 
 	var wroteHeader bool
@@ -169,16 +170,21 @@ func handleForwardResponseStreamError(wroteHeader bool, marshaler Marshaler, w h
 func streamChunk(result proto.Message, err error) map[string]proto.Message {
 	if err != nil {
 		grpcCode := codes.Unknown
+		grpcMessage := err.Error()
+		var grpcDetails []*any.Any
 		if s, ok := status.FromError(err); ok {
 			grpcCode = s.Code()
+			grpcMessage = s.Message()
+			grpcDetails = s.Proto().GetDetails()
 		}
 		httpCode := HTTPStatusFromCode(grpcCode)
 		return map[string]proto.Message{
 			"error": &internal.StreamError{
 				GrpcCode:   int32(grpcCode),
 				HttpCode:   int32(httpCode),
-				Message:    err.Error(),
+				Message:    grpcMessage,
 				HttpStatus: http.StatusText(httpCode),
+				Details:    grpcDetails,
 			},
 		}
 	}

runtime/handler_test.go

@@ -10,9 +10,11 @@ import (
 	"github.com/golang/protobuf/proto"
 	pb "github.com/grpc-ecosystem/grpc-gateway/examples/examplepb"
 	"github.com/grpc-ecosystem/grpc-gateway/runtime"
+	"github.com/grpc-ecosystem/grpc-gateway/runtime/internal"
 	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 func TestForwardResponseStream(t *testing.T) {
@@ -84,9 +86,32 @@ func TestForwardResponseStream(t *testing.T) {
 			w.Body.Close()
 
 			var want []byte
-			for _, msg := range tt.msgs {
+			for i, msg := range tt.msgs {
 				if msg.err != nil {
-					t.Skip("checking erorr encodings")
+					if i == 0 {
+						// Skip non-stream errors
+						t.Skip("checking error encodings")
+					}
+					st, _ := status.FromError(msg.err)
+					httpCode := runtime.HTTPStatusFromCode(st.Code())
+					b, err := marshaler.Marshal(map[string]proto.Message{
+						"error": &internal.StreamError{
+							GrpcCode:   int32(st.Code()),
+							HttpCode:   int32(httpCode),
+							Message:    st.Message(),
+							HttpStatus: http.StatusText(httpCode),
+							Details:    st.Proto().GetDetails(),
+						},
+					})
+					if err != nil {
+						t.Errorf("marshaler.Marshal() failed %v", err)
+					}
+					errBytes := body[len(want):]
+					if string(errBytes) != string(b) {
+						t.Errorf("ForwardResponseStream() = \"%s\" want \"%s\"", errBytes, b)
+					}
+
+					return
 				}
 				b, err := marshaler.Marshal(map[string]proto.Message{"result": msg.pb})
 				if err != nil {
@@ -103,17 +128,16 @@ func TestForwardResponseStream(t *testing.T) {
 	}
 }
 
-
 // A custom marshaler implementation, that doesn't implement the delimited interface
 type CustomMarshaler struct {
-    m *runtime.JSONPb
+	m *runtime.JSONPb
 }
-func (c *CustomMarshaler) Marshal(v interface{}) ([]byte, error) { return c.m.Marshal(v) }
-func (c *CustomMarshaler) Unmarshal(data []byte, v interface{}) error { return c.m.Unmarshal(data, v) }
-func (c *CustomMarshaler) NewDecoder(r io.Reader) runtime.Decoder { return c.m.NewDecoder(r) }
-func (c *CustomMarshaler) NewEncoder(w io.Writer) runtime.Encoder { return c.m.NewEncoder(w) }
-func (c *CustomMarshaler) ContentType() string { return c.m.ContentType() }
 
+func (c *CustomMarshaler) Marshal(v interface{}) ([]byte, error)      { return c.m.Marshal(v) }
+func (c *CustomMarshaler) Unmarshal(data []byte, v interface{}) error { return c.m.Unmarshal(data, v) }
+func (c *CustomMarshaler) NewDecoder(r io.Reader) runtime.Decoder     { return c.m.NewDecoder(r) }
+func (c *CustomMarshaler) NewEncoder(w io.Writer) runtime.Encoder     { return c.m.NewEncoder(w) }
+func (c *CustomMarshaler) ContentType() string                        { return c.m.ContentType() }
 
 func TestForwardResponseStreamCustomMarshaler(t *testing.T) {
 	type msg struct {

runtime/internal/stream_chunk.proto

@@ -2,11 +2,14 @@ syntax = "proto3";
 package grpc.gateway.runtime;
 option go_package = "internal";
 
+import "google/protobuf/any.proto";
+
 // StreamError is a response type which is returned when
 // streaming rpc returns an error.
 message StreamError {
 	int32 grpc_code = 1;
 	int32 http_code = 2;
 	string message = 3;
 	string http_status = 4;
+	repeated google.protobuf.Any details = 5;
 }