add grpc-proxy (github.com/mwitkow/grpc-proxy)

Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>

proxy/testservice/ping.go

@@ -0,0 +1,168 @@
+package testservice
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"golang.org/x/sync/errgroup"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
+	"google.golang.org/protobuf/types/known/emptypb"
+)
+
+var DefaultTestServiceServer = defaultPingServer{}
+
+const (
+	PingHeader      = "ping-header"
+	PingHeaderCts   = "Arbitrary header text"
+	PingTrailer     = "ping-trailer"
+	PingTrailerCts  = "Arbitrary trailer text"
+	PingEchoHeader  = "ping-echo-header"
+	PingEchoTrailer = "ping-echo-trailer"
+)
+
+// defaultPingServer is the canonical implementation of a TestServiceServer.
+type defaultPingServer struct {
+	UnsafeTestServiceServer
+}
+
+func (s defaultPingServer) PingEmpty(ctx context.Context, empty *emptypb.Empty) (*PingResponse, error) {
+	if err := s.sendHeader(ctx); err != nil {
+		return nil, err
+	}
+	if err := s.setTrailer(ctx); err != nil {
+		return nil, err
+	}
+	return &PingResponse{}, nil
+}
+
+func (s defaultPingServer) Ping(ctx context.Context, request *PingRequest) (*PingResponse, error) {
+	if err := s.sendHeader(ctx); err != nil {
+		return nil, err
+	}
+	if err := s.setTrailer(ctx); err != nil {
+		return nil, err
+	}
+
+	return &PingResponse{Value: request.Value}, nil
+}
+
+func (s defaultPingServer) PingError(ctx context.Context, request *PingRequest) (*emptypb.Empty, error) {
+	if err := s.sendHeader(ctx); err != nil {
+		return nil, err
+	}
+	if err := s.setTrailer(ctx); err != nil {
+		return nil, err
+	}
+	return nil, status.Error(codes.Unknown, "Something is wrong and this is a message that describes it")
+}
+
+func (s defaultPingServer) PingList(request *PingRequest, server TestService_PingListServer) error {
+	if err := s.sendHeader(server.Context()); err != nil {
+		return err
+	}
+	s.setStreamTrailer(server)
+	for i := 0; i < 10; i++ {
+		if err := server.Send(&PingResponse{
+			Value:   request.Value,
+			Counter: int32(i),
+		}); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s defaultPingServer) PingStream(server TestService_PingStreamServer) error {
+	g, ctx := errgroup.WithContext(context.Background())
+
+	if err := s.sendHeader(server.Context()); err != nil {
+		return err
+	}
+
+	pings := make(chan *PingRequest)
+	g.Go(func() error {
+		defer close(pings)
+		for {
+			m, err := server.Recv()
+			if err != nil {
+				if err == io.EOF {
+					return nil
+				}
+				return err
+			}
+			select {
+			case pings <- m:
+			case <-ctx.Done():
+				return ctx.Err()
+			}
+		}
+	})
+	g.Go(func() error {
+		var i int32
+		for m := range pings {
+			if err := server.Send(&PingResponse{
+				Value:   m.Value,
+				Counter: i,
+			}); err != nil {
+				return err
+			}
+			i++
+		}
+		return nil
+	})
+
+	return g.Wait()
+}
+
+func (s *defaultPingServer) sendHeader(ctx context.Context) error {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		md = metadata.New(nil)
+	}
+
+	if tvs := md.Get(PingEchoHeader); len(tvs) > 0 {
+		md.Append(PingEchoHeader, tvs...)
+	}
+
+	md.Append(PingHeader, PingHeaderCts)
+
+	if err := grpc.SendHeader(ctx, md); err != nil {
+		return fmt.Errorf("setting header: %w", err)
+	}
+	return nil
+}
+
+func (s *defaultPingServer) setTrailer(ctx context.Context) error {
+	md := s.buildTrailer(ctx)
+
+	if err := grpc.SetTrailer(ctx, md); err != nil {
+		return fmt.Errorf("setting trailer: %w", err)
+	}
+
+	return nil
+}
+
+func (s *defaultPingServer) buildTrailer(ctx context.Context) metadata.MD {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		md = metadata.New(nil)
+	}
+
+	if tvs := md.Get(PingEchoTrailer); len(tvs) > 0 {
+		md.Append(PingEchoTrailer, tvs...)
+	}
+
+	md.Append(PingTrailer, PingTrailerCts)
+
+	return md
+}
+
+func (s defaultPingServer) setStreamTrailer(server grpc.ServerStream) {
+	server.SetTrailer(s.buildTrailer(server.Context()))
+}
+
+var _ TestServiceServer = (*defaultPingServer)(nil)