Add support for grpc.SupportPackageIsVersion3 back (#1331)

* Support byte slice file descriptor as metadata and add SupportPackageIsVersion3 back

* add v3 test, generate testv3.pb.go with old codegen

reflection/grpc_testingv3/testv3.pb.go

@@ -0,0 +1,236 @@
+// Code generated by protoc-gen-go.
+// source: testv3.proto
+// DO NOT EDIT!
+
+/*
+Package grpc_testingv3 is a generated protocol buffer package.
+
+It is generated from these files:
+	testv3.proto
+
+It has these top-level messages:
+	SearchResponseV3
+	SearchRequestV3
+*/
+package grpc_testingv3
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+import (
+	context "golang.org/x/net/context"
+	grpc "google.golang.org/grpc"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+type SearchResponseV3 struct {
+	Results []*SearchResponseV3_Result `protobuf:"bytes,1,rep,name=results" json:"results,omitempty"`
+}
+
+func (m *SearchResponseV3) Reset()                    { *m = SearchResponseV3{} }
+func (m *SearchResponseV3) String() string            { return proto.CompactTextString(m) }
+func (*SearchResponseV3) ProtoMessage()               {}
+func (*SearchResponseV3) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *SearchResponseV3) GetResults() []*SearchResponseV3_Result {
+	if m != nil {
+		return m.Results
+	}
+	return nil
+}
+
+type SearchResponseV3_Result struct {
+	Url      string   `protobuf:"bytes,1,opt,name=url" json:"url,omitempty"`
+	Title    string   `protobuf:"bytes,2,opt,name=title" json:"title,omitempty"`
+	Snippets []string `protobuf:"bytes,3,rep,name=snippets" json:"snippets,omitempty"`
+}
+
+func (m *SearchResponseV3_Result) Reset()                    { *m = SearchResponseV3_Result{} }
+func (m *SearchResponseV3_Result) String() string            { return proto.CompactTextString(m) }
+func (*SearchResponseV3_Result) ProtoMessage()               {}
+func (*SearchResponseV3_Result) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0, 0} }
+
+type SearchRequestV3 struct {
+	Query string `protobuf:"bytes,1,opt,name=query" json:"query,omitempty"`
+}
+
+func (m *SearchRequestV3) Reset()                    { *m = SearchRequestV3{} }
+func (m *SearchRequestV3) String() string            { return proto.CompactTextString(m) }
+func (*SearchRequestV3) ProtoMessage()               {}
+func (*SearchRequestV3) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func init() {
+	proto.RegisterType((*SearchResponseV3)(nil), "grpc.testingv3.SearchResponseV3")
+	proto.RegisterType((*SearchResponseV3_Result)(nil), "grpc.testingv3.SearchResponseV3.Result")
+	proto.RegisterType((*SearchRequestV3)(nil), "grpc.testingv3.SearchRequestV3")
+}
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ context.Context
+var _ grpc.ClientConn
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the grpc package it is being compiled against.
+const _ = grpc.SupportPackageIsVersion3
+
+// Client API for SearchServiceV3 service
+
+type SearchServiceV3Client interface {
+	Search(ctx context.Context, in *SearchRequestV3, opts ...grpc.CallOption) (*SearchResponseV3, error)
+	StreamingSearch(ctx context.Context, opts ...grpc.CallOption) (SearchServiceV3_StreamingSearchClient, error)
+}
+
+type searchServiceV3Client struct {
+	cc *grpc.ClientConn
+}
+
+func NewSearchServiceV3Client(cc *grpc.ClientConn) SearchServiceV3Client {
+	return &searchServiceV3Client{cc}
+}
+
+func (c *searchServiceV3Client) Search(ctx context.Context, in *SearchRequestV3, opts ...grpc.CallOption) (*SearchResponseV3, error) {
+	out := new(SearchResponseV3)
+	err := grpc.Invoke(ctx, "/grpc.testingv3.SearchServiceV3/Search", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func (c *searchServiceV3Client) StreamingSearch(ctx context.Context, opts ...grpc.CallOption) (SearchServiceV3_StreamingSearchClient, error) {
+	stream, err := grpc.NewClientStream(ctx, &_SearchServiceV3_serviceDesc.Streams[0], c.cc, "/grpc.testingv3.SearchServiceV3/StreamingSearch", opts...)
+	if err != nil {
+		return nil, err
+	}
+	x := &searchServiceV3StreamingSearchClient{stream}
+	return x, nil
+}
+
+type SearchServiceV3_StreamingSearchClient interface {
+	Send(*SearchRequestV3) error
+	Recv() (*SearchResponseV3, error)
+	grpc.ClientStream
+}
+
+type searchServiceV3StreamingSearchClient struct {
+	grpc.ClientStream
+}
+
+func (x *searchServiceV3StreamingSearchClient) Send(m *SearchRequestV3) error {
+	return x.ClientStream.SendMsg(m)
+}
+
+func (x *searchServiceV3StreamingSearchClient) Recv() (*SearchResponseV3, error) {
+	m := new(SearchResponseV3)
+	if err := x.ClientStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+// Server API for SearchServiceV3 service
+
+type SearchServiceV3Server interface {
+	Search(context.Context, *SearchRequestV3) (*SearchResponseV3, error)
+	StreamingSearch(SearchServiceV3_StreamingSearchServer) error
+}
+
+func RegisterSearchServiceV3Server(s *grpc.Server, srv SearchServiceV3Server) {
+	s.RegisterService(&_SearchServiceV3_serviceDesc, srv)
+}
+
+func _SearchServiceV3_Search_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(SearchRequestV3)
+	if err := dec(in); err != nil {
+		return nil, err
+	}
+	if interceptor == nil {
+		return srv.(SearchServiceV3Server).Search(ctx, in)
+	}
+	info := &grpc.UnaryServerInfo{
+		Server:     srv,
+		FullMethod: "/grpc.testingv3.SearchServiceV3/Search",
+	}
+	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
+		return srv.(SearchServiceV3Server).Search(ctx, req.(*SearchRequestV3))
+	}
+	return interceptor(ctx, in, info, handler)
+}
+
+func _SearchServiceV3_StreamingSearch_Handler(srv interface{}, stream grpc.ServerStream) error {
+	return srv.(SearchServiceV3Server).StreamingSearch(&searchServiceV3StreamingSearchServer{stream})
+}
+
+type SearchServiceV3_StreamingSearchServer interface {
+	Send(*SearchResponseV3) error
+	Recv() (*SearchRequestV3, error)
+	grpc.ServerStream
+}
+
+type searchServiceV3StreamingSearchServer struct {
+	grpc.ServerStream
+}
+
+func (x *searchServiceV3StreamingSearchServer) Send(m *SearchResponseV3) error {
+	return x.ServerStream.SendMsg(m)
+}
+
+func (x *searchServiceV3StreamingSearchServer) Recv() (*SearchRequestV3, error) {
+	m := new(SearchRequestV3)
+	if err := x.ServerStream.RecvMsg(m); err != nil {
+		return nil, err
+	}
+	return m, nil
+}
+
+var _SearchServiceV3_serviceDesc = grpc.ServiceDesc{
+	ServiceName: "grpc.testingv3.SearchServiceV3",
+	HandlerType: (*SearchServiceV3Server)(nil),
+	Methods: []grpc.MethodDesc{
+		{
+			MethodName: "Search",
+			Handler:    _SearchServiceV3_Search_Handler,
+		},
+	},
+	Streams: []grpc.StreamDesc{
+		{
+			StreamName:    "StreamingSearch",
+			Handler:       _SearchServiceV3_StreamingSearch_Handler,
+			ServerStreams: true,
+			ClientStreams: true,
+		},
+	},
+	Metadata: fileDescriptor0,
+}
+
+func init() { proto.RegisterFile("testv3.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 240 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x91, 0x41, 0x4b, 0xc3, 0x40,
+	0x10, 0x85, 0x59, 0x83, 0xd1, 0x8e, 0x62, 0xcb, 0xe2, 0x21, 0xe4, 0x62, 0xe8, 0xa5, 0x39, 0x2d,
+	0xd2, 0xfd, 0x05, 0x9e, 0xf5, 0xb4, 0x81, 0xe2, 0xb5, 0x86, 0x21, 0x2e, 0xc4, 0x64, 0x3b, 0x33,
+	0x09, 0xf8, 0x7b, 0xfc, 0x13, 0xfe, 0x3c, 0x49, 0xd2, 0x08, 0x0a, 0xe2, 0xa5, 0xb7, 0x7d, 0x8f,
+	0xf7, 0xbe, 0xe5, 0x31, 0x70, 0x2d, 0xc8, 0xd2, 0x5b, 0x13, 0xa8, 0x95, 0x56, 0xdf, 0x54, 0x14,
+	0x4a, 0x33, 0x58, 0xbe, 0xa9, 0x7a, 0xbb, 0xfe, 0x50, 0xb0, 0x2a, 0x70, 0x4f, 0xe5, 0xab, 0x43,
+	0x0e, 0x6d, 0xc3, 0xb8, 0xb3, 0xfa, 0x01, 0x2e, 0x08, 0xb9, 0xab, 0x85, 0x13, 0x95, 0x45, 0xf9,
+	0xd5, 0x76, 0x63, 0x7e, 0xd6, 0xcc, 0xef, 0x8a, 0x71, 0x63, 0xde, 0xcd, 0xbd, 0xf4, 0x09, 0xe2,
+	0xc9, 0xd2, 0x2b, 0x88, 0x3a, 0xaa, 0x13, 0x95, 0xa9, 0x7c, 0xe1, 0x86, 0xa7, 0xbe, 0x85, 0x73,
+	0xf1, 0x52, 0x63, 0x72, 0x36, 0x7a, 0x93, 0xd0, 0x29, 0x5c, 0x72, 0xe3, 0x43, 0x40, 0xe1, 0x24,
+	0xca, 0xa2, 0x7c, 0xe1, 0xbe, 0xf5, 0x7a, 0x03, 0xcb, 0xf9, 0xc7, 0x43, 0x87, 0x2c, 0x3b, 0x3b,
+	0x40, 0x0e, 0x1d, 0xd2, 0xfb, 0x11, 0x3c, 0x89, 0xed, 0xa7, 0x9a, 0x93, 0x05, 0x52, 0xef, 0xcb,
+	0x61, 0xcd, 0x23, 0xc4, 0x93, 0xa5, 0xef, 0xfe, 0x9a, 0x71, 0x84, 0xa6, 0xd9, 0x7f, 0x3b, 0xf5,
+	0x33, 0x2c, 0x0b, 0x21, 0xdc, 0xbf, 0xf9, 0xa6, 0x3a, 0x19, 0x35, 0x57, 0xf7, 0xea, 0x25, 0x1e,
+	0x0f, 0x64, 0xbf, 0x02, 0x00, 0x00, 0xff, 0xff, 0xd4, 0xe6, 0xa0, 0xf9, 0xb0, 0x01, 0x00, 0x00,
+}

reflection/grpc_testingv3/testv3.proto

@@ -0,0 +1,21 @@
+syntax = "proto3";
+
+package grpc.testingv3;
+
+message SearchResponseV3 {
+  message Result {
+    string url = 1;
+    string title = 2;
+    repeated string snippets = 3;
+  }
+  repeated Result results = 1;
+}
+
+message SearchRequestV3 {
+  string query = 1;
+}
+
+service SearchServiceV3 {
+  rpc Search(SearchRequestV3) returns (SearchResponseV3);
+  rpc StreamingSearch(stream SearchRequestV3) returns (stream SearchResponseV3);
+}

reflection/serverreflection.go

@@ -212,6 +212,24 @@ func (s *serverReflectionServer) serviceMetadataForSymbol(name string) (interfac
 	return nil, fmt.Errorf("unknown symbol: %v", name)
 }
 
+// parseMetadata finds the file descriptor bytes specified meta.
+// For SupportPackageIsVersion4, m is the name of the proto file, we
+// call proto.FileDescriptor to get the byte slice.
+// For SupportPackageIsVersion3, m is a byte slice itself.
+func parseMetadata(meta interface{}) ([]byte, bool) {
+	// Check if meta is the file name.
+	if fileNameForMeta, ok := meta.(string); ok {
+		return proto.FileDescriptor(fileNameForMeta), true
+	}
+
+	// Check if meta is the byte slice.
+	if enc, ok := meta.([]byte); ok {
+		return enc, true
+	}
+
+	return nil, false
+}
+
 // fileDescEncodingContainingSymbol finds the file descriptor containing the given symbol,
 // does marshalling on it and returns the marshalled result.
 // The given symbol can be a type, a service or a method.
@@ -234,12 +252,11 @@ func (s *serverReflectionServer) fileDescEncodingContainingSymbol(name string) (
 		}
 
 		// Metadata not valid.
-		fileNameForMeta, ok := meta.(string)
+		enc, ok := parseMetadata(meta)
 		if !ok {
 			return nil, fmt.Errorf("invalid file descriptor for symbol: %v", name)
 		}
 
-		enc := proto.FileDescriptor(fileNameForMeta)
 		fd, err = s.decodeFileDesc(enc)
 		if err != nil {
 			return nil, err

reflection/serverreflection_test.go

@@ -31,17 +31,20 @@ import (
 	"google.golang.org/grpc"
 	rpb "google.golang.org/grpc/reflection/grpc_reflection_v1alpha"
 	pb "google.golang.org/grpc/reflection/grpc_testing"
+	pbv3 "google.golang.org/grpc/reflection/grpc_testingv3"
 )
 
 var (
 	s = &serverReflectionServer{}
 	// fileDescriptor of each test proto file.
 	fdTest       *dpb.FileDescriptorProto
+	fdTestv3     *dpb.FileDescriptorProto
 	fdProto2     *dpb.FileDescriptorProto
 	fdProto2Ext  *dpb.FileDescriptorProto
 	fdProto2Ext2 *dpb.FileDescriptorProto
 	// fileDescriptor marshalled.
 	fdTestByte       []byte
+	fdTestv3Byte     []byte
 	fdProto2Byte     []byte
 	fdProto2ExtByte  []byte
 	fdProto2Ext2Byte []byte
@@ -65,6 +68,7 @@ func loadFileDesc(filename string) (*dpb.FileDescriptorProto, []byte) {
 
 func init() {
 	fdTest, fdTestByte = loadFileDesc("test.proto")
+	fdTestv3, fdTestv3Byte = loadFileDesc("testv3.proto")
 	fdProto2, fdProto2Byte = loadFileDesc("proto2.proto")
 	fdProto2Ext, fdProto2ExtByte = loadFileDesc("proto2_ext.proto")
 	fdProto2Ext2, fdProto2Ext2Byte = loadFileDesc("proto2_ext2.proto")
@@ -163,6 +167,16 @@ func (s *server) StreamingSearch(stream pb.SearchService_StreamingSearchServer)
 	return nil
 }
 
+type serverV3 struct{}
+
+func (s *serverV3) Search(ctx context.Context, in *pbv3.SearchRequestV3) (*pbv3.SearchResponseV3, error) {
+	return &pbv3.SearchResponseV3{}, nil
+}
+
+func (s *serverV3) StreamingSearch(stream pbv3.SearchServiceV3_StreamingSearchServer) error {
+	return nil
+}
+
 func TestReflectionEnd2end(t *testing.T) {
 	// Start server.
 	lis, err := net.Listen("tcp", "localhost:0")
@@ -171,6 +185,7 @@ func TestReflectionEnd2end(t *testing.T) {
 	}
 	s := grpc.NewServer()
 	pb.RegisterSearchServiceServer(s, &server{})
+	pbv3.RegisterSearchServiceV3Server(s, &serverV3{})
 	// Register reflection service on s.
 	Register(s)
 	go s.Serve(lis)
@@ -271,6 +286,11 @@ func testFileContainingSymbol(t *testing.T, stream rpb.ServerReflection_ServerRe
 		{"grpc.testing.SearchService.StreamingSearch", fdTestByte},
 		{"grpc.testing.SearchResponse", fdTestByte},
 		{"grpc.testing.ToBeExtended", fdProto2Byte},
+		// Test support package v3.
+		{"grpc.testingv3.SearchServiceV3", fdTestv3Byte},
+		{"grpc.testingv3.SearchServiceV3.Search", fdTestv3Byte},
+		{"grpc.testingv3.SearchServiceV3.StreamingSearch", fdTestv3Byte},
+		{"grpc.testingv3.SearchResponseV3", fdTestv3Byte},
 	} {
 		if err := stream.Send(&rpb.ServerReflectionRequest{
 			MessageRequest: &rpb.ServerReflectionRequest_FileContainingSymbol{
@@ -469,7 +489,11 @@ func testListServices(t *testing.T, stream rpb.ServerReflection_ServerReflection
 	switch r.MessageResponse.(type) {
 	case *rpb.ServerReflectionResponse_ListServicesResponse:
 		services := r.GetListServicesResponse().Service
-		want := []string{"grpc.testing.SearchService", "grpc.reflection.v1alpha.ServerReflection"}
+		want := []string{
+			"grpc.testingv3.SearchServiceV3",
+			"grpc.testing.SearchService",
+			"grpc.reflection.v1alpha.ServerReflection",
+		}
 		// Compare service names in response with want.
 		if len(services) != len(want) {
 			t.Errorf("= %v, want service names: %v", services, want)

rpc_util.go

@@ -504,6 +504,12 @@ func getMaxSize(mcMax, doptMax *int, defaultVal int) *int {
 	return doptMax
 }
 
+// SupportPackageIsVersion3 is referenced from generated protocol buffer files.
+// The latest support package version is 4.
+// SupportPackageIsVersion3 is kept for compability. It will be removed in the
+// next support package version update.
+const SupportPackageIsVersion3 = true
+
 // SupportPackageIsVersion4 is referenced from generated protocol buffer files
 // to assert that that code is compatible with this version of the grpc package.
 //