From 9591a64e090822adce997963f8b5a7d9853a2f81 Mon Sep 17 00:00:00 2001 From: Adphi Date: Wed, 16 Oct 2024 15:04:43 +0200 Subject: [PATCH] add grpc-proxy (github.com/mwitkow/grpc-proxy) Signed-off-by: Adphi --- proxy/README.md | 83 ++++++++ proxy/codec.go | 69 +++++++ proxy/codec_test.go | 23 +++ proxy/director.go | 25 +++ proxy/doc.go | 15 ++ proxy/examples_test.go | 70 +++++++ proxy/handler.go | 160 ++++++++++++++++ proxy/handler_test.go | 262 +++++++++++++++++++++++++ proxy/proxy.go | 33 ++++ proxy/proxy_test.go | 211 ++++++++++++++++++++ proxy/testservice/Makefile | 9 + proxy/testservice/ping.go | 168 ++++++++++++++++ proxy/testservice/server/main.go | 54 ++++++ proxy/testservice/test.pb.go | 255 +++++++++++++++++++++++++ proxy/testservice/test.proto | 30 +++ proxy/testservice/test_grpc.pb.go | 306 ++++++++++++++++++++++++++++++ proxy/testservice/testping.go | 158 +++++++++++++++ 17 files changed, 1931 insertions(+) create mode 100644 proxy/README.md create mode 100644 proxy/codec.go create mode 100644 proxy/codec_test.go create mode 100644 proxy/director.go create mode 100644 proxy/doc.go create mode 100644 proxy/examples_test.go create mode 100644 proxy/handler.go create mode 100644 proxy/handler_test.go create mode 100644 proxy/proxy.go create mode 100644 proxy/proxy_test.go create mode 100644 proxy/testservice/Makefile create mode 100644 proxy/testservice/ping.go create mode 100644 proxy/testservice/server/main.go create mode 100644 proxy/testservice/test.pb.go create mode 100644 proxy/testservice/test.proto create mode 100644 proxy/testservice/test_grpc.pb.go create mode 100644 proxy/testservice/testping.go diff --git a/proxy/README.md b/proxy/README.md new file mode 100644 index 0000000..0b3f876 --- /dev/null +++ b/proxy/README.md @@ -0,0 +1,83 @@ +# gRPC Proxy + +[![Travis Build](https://travis-ci.org/mwitkow/grpc-proxy.svg?branch=master)](https://travis-ci.org/mwitkow/grpc-proxy) +[![Go Report Card](https://goreportcard.com/badge/github.com/mwitkow/grpc-proxy)](https://goreportcard.com/report/github.com/mwitkow/grpc-proxy) +[![Go Reference](https://pkg.go.dev/badge/github.com/mwitkow/grpc-proxy.svg)](https://pkg.go.dev/github.com/mwitkow/grpc-proxy) +[![Apache 2.0 License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](LICENSE) + +[gRPC Go](https://github.com/grpc/grpc-go) Proxy server + +## Project Goal + +Build a transparent reverse proxy for gRPC targets that will make it easy to expose gRPC services +over the internet. This includes: + * no needed knowledge of the semantics of requests exchanged in the call (independent rollouts) + * easy, declarative definition of backends and their mappings to frontends + * simple round-robin load balancing of inbound requests from a single connection to multiple backends + +The project now exists as a **proof of concept**, with the key piece being the `proxy` package that +is a generic gRPC reverse proxy handler. + +## Proxy Handler + +The package [`proxy`](proxy/) contains a generic gRPC reverse proxy handler that allows a gRPC server to +not know about registered handlers or their data types. Please consult the docs, here's an exaple usage. + +You can call `proxy.NewProxy` to create a `*grpc.Server` that proxies requests. +```go +proxy := proxy.NewProxy(clientConn) +``` + +More advanced users will want to define a `StreamDirector` that can make more complex decisions on what +to do with the request. +```go +director = func(ctx context.Context, fullMethodName string) (context.Context, *grpc.ClientConn, error) { + md, _ := metadata.FromIncomingContext(ctx) + outCtx = metadata.NewOutgoingContext(ctx, md.Copy()) + return outCtx, cc, nil + + // Make sure we never forward internal services. + if strings.HasPrefix(fullMethodName, "/com.example.internal.") { + return outCtx, nil, status.Errorf(codes.Unimplemented, "Unknown method") + } + + if ok { + // Decide on which backend to dial + if val, exists := md[":authority"]; exists && val[0] == "staging.api.example.com" { + // Make sure we use DialContext so the dialing can be cancelled/time out together with the context. + return outCtx, grpc.DialContext(ctx, "api-service.staging.svc.local", grpc.WithCodec(proxy.Codec())), nil + } else if val, exists := md[":authority"]; exists && val[0] == "api.example.com" { + return outCtx, grpc.DialContext(ctx, "api-service.prod.svc.local", grpc.WithCodec(proxy.Codec())), nil + } + } + return outCtx, nil, status.Errorf(codes.Unimplemented, "Unknown method") +} +``` + +Then you need to register it with a `grpc.Server`. The server may have other handlers that will be served +locally. + +```go +server := grpc.NewServer( + grpc.CustomCodec(proxy.Codec()), + grpc.UnknownServiceHandler(proxy.TransparentHandler(director))) +pb_test.RegisterTestServiceServer(server, &testImpl{}) +``` + +## Testing +To make debugging a bit simpler, there are some helpers. + +`testservice` contains a method `TestTestServiceServerImpl` which performs a complete test against +the reference implementation of the `TestServiceServer`. + +In `proxy_test.go`, the test framework spins up a `TestServiceServer` that it tests the proxy +against. To make debugging a bit simpler (eg. if the developer needs to step into +`google.golang.org/grpc` methods), this `TestServiceServer` can be provided by a server by +passing `-test-backend=addr` to `go test`. A simple, local-only implementation of +`TestServiceServer` exists in [`testservice/server`](./testservice/server). + + +## License + +`grpc-proxy` is released under the Apache 2.0 license. See [LICENSE.txt](LICENSE.txt). + diff --git a/proxy/codec.go b/proxy/codec.go new file mode 100644 index 0000000..cd1a4be --- /dev/null +++ b/proxy/codec.go @@ -0,0 +1,69 @@ +package proxy + +import ( + "fmt" + + "google.golang.org/grpc" + "google.golang.org/protobuf/proto" +) + +// Codec returns a proxying grpc.Codec with the default protobuf codec as parent. +// +// See CodecWithParent. +// +// Deprecated: No longer necessary. +func Codec() grpc.Codec { + return CodecWithParent(&protoCodec{}) +} + +// CodecWithParent returns a proxying grpc.Codec with a user provided codec as parent. +// +// Deprecated: No longer necessary. +func CodecWithParent(fallback grpc.Codec) grpc.Codec { + return &rawCodec{fallback} +} + +type rawCodec struct { + parentCodec grpc.Codec +} + +type frame struct { + payload []byte +} + +func (c *rawCodec) Marshal(v interface{}) ([]byte, error) { + out, ok := v.(*frame) + if !ok { + return c.parentCodec.Marshal(v) + } + return out.payload, nil + +} + +func (c *rawCodec) Unmarshal(data []byte, v interface{}) error { + dst, ok := v.(*frame) + if !ok { + return c.parentCodec.Unmarshal(data, v) + } + dst.payload = data + return nil +} + +func (c *rawCodec) String() string { + return fmt.Sprintf("proxy>%s", c.parentCodec.String()) +} + +// protoCodec is a Codec implementation with protobuf. It is the default rawCodec for gRPC. +type protoCodec struct{} + +func (protoCodec) Marshal(v interface{}) ([]byte, error) { + return proto.Marshal(v.(proto.Message)) +} + +func (protoCodec) Unmarshal(data []byte, v interface{}) error { + return proto.Unmarshal(data, v.(proto.Message)) +} + +func (protoCodec) String() string { + return "proto" +} diff --git a/proxy/codec_test.go b/proxy/codec_test.go new file mode 100644 index 0000000..99569ac --- /dev/null +++ b/proxy/codec_test.go @@ -0,0 +1,23 @@ +package proxy + +import ( + "testing" + + "github.com/stretchr/testify/require" +) + +func TestCodec_ReadYourWrites(t *testing.T) { + framePtr := &frame{} + data := []byte{0xDE, 0xAD, 0xBE, 0xEF} + codec := rawCodec{} + require.NoError(t, codec.Unmarshal(data, framePtr), "unmarshalling must go ok") + out, err := codec.Marshal(framePtr) + require.NoError(t, err, "no marshal error") + require.Equal(t, data, out, "output and data must be the same") + + // reuse + require.NoError(t, codec.Unmarshal([]byte{0x55}, framePtr), "unmarshalling must go ok") + out, err = codec.Marshal(framePtr) + require.NoError(t, err, "no marshal error") + require.Equal(t, []byte{0x55}, out, "output and data must be the same") +} diff --git a/proxy/director.go b/proxy/director.go new file mode 100644 index 0000000..6104cbc --- /dev/null +++ b/proxy/director.go @@ -0,0 +1,25 @@ +// Copyright 2017 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +package proxy + +import ( + "context" + + "google.golang.org/grpc" +) + +// StreamDirector returns a gRPC ClientConn to be used to forward the call to. +// +// The presence of the `Context` allows for rich filtering, e.g. based on Metadata (headers). +// If no handling is meant to be done, a `codes.NotImplemented` gRPC error should be returned. +// +// The context returned from this function should be the context for the *outgoing* (to backend) call. In case you want +// to forward any Metadata between the inbound request and outbound requests, you should do it manually. However, you +// *must* propagate the cancel function (`context.WithCancel`) of the inbound context to the one returned. +// +// It is worth noting that the StreamDirector will be fired *after* all server-side stream interceptors +// are invoked. So decisions around authorization, monitoring etc. are better to be handled there. +// +// See the rather rich example. +type StreamDirector func(ctx context.Context, fullMethodName string) (context.Context, grpc.ClientConnInterface, error) diff --git a/proxy/doc.go b/proxy/doc.go new file mode 100644 index 0000000..613b5c4 --- /dev/null +++ b/proxy/doc.go @@ -0,0 +1,15 @@ +// Copyright 2017 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +/* +Package proxy provides a reverse proxy handler for gRPC. + +The implementation allows a grpc.Server to pass a received ServerStream to a ClientStream without understanding +the semantics of the messages exchanged. It basically provides a transparent reverse-proxy. + +This package is intentionally generic, exposing a StreamDirector function that allows users of this package +to implement whatever logic of backend-picking, dialing and service verification to perform. + +See examples on documented functions. +*/ +package proxy diff --git a/proxy/examples_test.go b/proxy/examples_test.go new file mode 100644 index 0000000..358af7b --- /dev/null +++ b/proxy/examples_test.go @@ -0,0 +1,70 @@ +// Copyright 2017 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +package proxy_test + +import ( + "context" + "log" + "strings" + + "google.golang.org/grpc" + "google.golang.org/grpc/codes" + "google.golang.org/grpc/metadata" + "google.golang.org/grpc/status" + + "go.linka.cloud/grpc-toolkit/proxy" +) + +var ( + director proxy.StreamDirector +) + +func ExampleNewProxy() { + dst, err := grpc.Dial("example.com") + if err != nil { + log.Fatalf("dialing example.org: %v", err) + } + proxy := proxy.NewProxy(dst) + _ = proxy +} + +func ExampleRegisterService() { + // A gRPC server with the proxying codec enabled. + server := grpc.NewServer() + // Register a TestService with 4 of its methods explicitly. + proxy.RegisterService(server, director, + "mwitkow.testproto.TestService", + "PingEmpty", "Ping", "PingError", "PingList") +} + +func ExampleTransparentHandler() { + grpc.NewServer( + grpc.UnknownServiceHandler(proxy.TransparentHandler(director))) +} + +// Provides a simple example of a director that shields internal services and dials a staging or production backend. +// This is a *very naive* implementation that creates a new connection on every request. Consider using pooling. +func ExampleStreamDirector() { + director = func(ctx context.Context, fullMethodName string) (context.Context, grpc.ClientConnInterface, error) { + // Make sure we never forward internal services. + if strings.HasPrefix(fullMethodName, "/com.example.internal.") { + return nil, nil, status.Errorf(codes.Unimplemented, "Unknown method") + } + md, ok := metadata.FromIncomingContext(ctx) + // Copy the inbound metadata explicitly. + outCtx := metadata.NewOutgoingContext(ctx, md.Copy()) + if ok { + // Decide on which backend to dial + if val, exists := md[":authority"]; exists && val[0] == "staging.api.example.com" { + // Make sure we use DialContext so the dialing can be cancelled/time out together with the context. + conn, err := grpc.DialContext(ctx, "api-service.staging.svc.local") + return outCtx, conn, err + } else if val, exists := md[":authority"]; exists && val[0] == "api.example.com" { + conn, err := grpc.DialContext(ctx, "api-service.prod.svc.local") + return outCtx, conn, err + } + } + return nil, nil, status.Errorf(codes.Unimplemented, "Unknown method") + } +} diff --git a/proxy/handler.go b/proxy/handler.go new file mode 100644 index 0000000..e4edbb9 --- /dev/null +++ b/proxy/handler.go @@ -0,0 +1,160 @@ +// Copyright 2017 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +package proxy + +import ( + "context" + "io" + + "google.golang.org/grpc" + "google.golang.org/grpc/codes" + "google.golang.org/grpc/status" + "google.golang.org/protobuf/types/known/emptypb" +) + +var ( + clientStreamDescForProxying = &grpc.StreamDesc{ + ServerStreams: true, + ClientStreams: true, + } +) + +// RegisterService sets up a proxy handler for a particular gRPC service and method. +// The behaviour is the same as if you were registering a handler method, e.g. from a generated pb.go file. +func RegisterService(server *grpc.Server, director StreamDirector, serviceName string, methodNames ...string) { + streamer := &handler{director} + fakeDesc := &grpc.ServiceDesc{ + ServiceName: serviceName, + HandlerType: (*interface{})(nil), + } + for _, m := range methodNames { + streamDesc := grpc.StreamDesc{ + StreamName: m, + Handler: streamer.handler, + ServerStreams: true, + ClientStreams: true, + } + fakeDesc.Streams = append(fakeDesc.Streams, streamDesc) + } + server.RegisterService(fakeDesc, streamer) +} + +// TransparentHandler returns a handler that attempts to proxy all requests that are not registered in the server. +// The indented use here is as a transparent proxy, where the server doesn't know about the services implemented by the +// backends. It should be used as a `grpc.UnknownServiceHandler`. +func TransparentHandler(director StreamDirector) grpc.StreamHandler { + streamer := &handler{director: director} + return streamer.handler +} + +type handler struct { + director StreamDirector +} + +// handler is where the real magic of proxying happens. +// It is invoked like any gRPC server stream and uses the emptypb.Empty type server +// to proxy calls between the input and output streams. +func (s *handler) handler(srv interface{}, serverStream grpc.ServerStream) error { + // little bit of gRPC internals never hurt anyone + fullMethodName, ok := grpc.MethodFromServerStream(serverStream) + if !ok { + return status.Errorf(codes.Internal, "lowLevelServerStream not exists in context") + } + // We require that the director's returned context inherits from the serverStream.Context(). + outgoingCtx, backendConn, err := s.director(serverStream.Context(), fullMethodName) + if err != nil { + return err + } + + clientCtx, clientCancel := context.WithCancel(outgoingCtx) + defer clientCancel() + // TODO(mwitkow): Add a `forwarded` header to metadata, https://en.wikipedia.org/wiki/X-Forwarded-For. + clientStream, err := backendConn.NewStream(clientCtx, clientStreamDescForProxying, fullMethodName) + if err != nil { + return err + } + // Explicitly *do not close* s2cErrChan and c2sErrChan, otherwise the select below will not terminate. + // Channels do not have to be closed, it is just a control flow mechanism, see + // https://groups.google.com/forum/#!msg/golang-nuts/pZwdYRGxCIk/qpbHxRRPJdUJ + s2cErrChan := s.forwardServerToClient(serverStream, clientStream) + c2sErrChan := s.forwardClientToServer(clientStream, serverStream) + // We don't know which side is going to stop sending first, so we need a select between the two. + for i := 0; i < 2; i++ { + select { + case s2cErr := <-s2cErrChan: + if s2cErr == io.EOF { + // this is the happy case where the sender has encountered io.EOF, and won't be sending anymore./ + // the clientStream>serverStream may continue pumping though. + clientStream.CloseSend() + } else { + // however, we may have gotten a receive error (stream disconnected, a read error etc) in which case we need + // to cancel the clientStream to the backend, let all of its goroutines be freed up by the CancelFunc and + // exit with an error to the stack + clientCancel() + return status.Errorf(codes.Internal, "failed proxying s2c: %v", s2cErr) + } + case c2sErr := <-c2sErrChan: + // This happens when the clientStream has nothing else to offer (io.EOF), returned a gRPC error. In those two + // cases we may have received Trailers as part of the call. In case of other errors (stream closed) the trailers + // will be nil. + serverStream.SetTrailer(clientStream.Trailer()) + // c2sErr will contain RPC error from client code. If not io.EOF return the RPC error as server stream error. + if c2sErr != io.EOF { + return c2sErr + } + return nil + } + } + return status.Errorf(codes.Internal, "gRPC proxying should never reach this stage.") +} + +func (s *handler) forwardClientToServer(src grpc.ClientStream, dst grpc.ServerStream) chan error { + ret := make(chan error, 1) + go func() { + f := &emptypb.Empty{} + for i := 0; ; i++ { + if err := src.RecvMsg(f); err != nil { + ret <- err // this can be io.EOF which is happy case + break + } + if i == 0 { + // This is a bit of a hack, but client to server headers are only readable after first client msg is + // received but must be written to server stream before the first msg is flushed. + // This is the only place to do it nicely. + md, err := src.Header() + if err != nil { + ret <- err + break + } + if err := dst.SendHeader(md); err != nil { + ret <- err + break + } + } + if err := dst.SendMsg(f); err != nil { + ret <- err + break + } + } + }() + return ret +} + +func (s *handler) forwardServerToClient(src grpc.ServerStream, dst grpc.ClientStream) chan error { + ret := make(chan error, 1) + go func() { + f := &emptypb.Empty{} + for i := 0; ; i++ { + if err := src.RecvMsg(f); err != nil { + ret <- err // this can be io.EOF which is happy case + break + } + if err := dst.SendMsg(f); err != nil { + ret <- err + break + } + } + }() + return ret +} diff --git a/proxy/handler_test.go b/proxy/handler_test.go new file mode 100644 index 0000000..aca4e96 --- /dev/null +++ b/proxy/handler_test.go @@ -0,0 +1,262 @@ +// Copyright 2017 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +package proxy_test + +import ( + "context" + "fmt" + "io" + "net" + "strings" + "testing" + "time" + + "github.com/stretchr/testify/assert" + "github.com/stretchr/testify/require" + "github.com/stretchr/testify/suite" + "google.golang.org/grpc" + "google.golang.org/grpc/codes" + "google.golang.org/grpc/metadata" + "google.golang.org/grpc/status" + "google.golang.org/protobuf/proto" + "google.golang.org/protobuf/types/known/emptypb" + + "go.linka.cloud/grpc-toolkit/proxy" + pb "go.linka.cloud/grpc-toolkit/proxy/testservice" +) + +const ( + pingDefaultValue = "I like kittens." + clientMdKey = "test-client-header" + serverHeaderMdKey = "test-client-header" + serverTrailerMdKey = "test-client-trailer" + + rejectingMdKey = "test-reject-rpc-if-in-context" + + countListResponses = 20 +) + +// asserting service is implemented on the server side and serves as a handler for stuff +type assertingService struct { + t *testing.T + pb.UnsafeTestServiceServer +} + +var _ pb.TestServiceServer = (*assertingService)(nil) + +func (s *assertingService) PingEmpty(ctx context.Context, _ *emptypb.Empty) (*pb.PingResponse, error) { + // Check that this call has client's metadata. + md, ok := metadata.FromIncomingContext(ctx) + assert.True(s.t, ok, "PingEmpty call must have metadata in context") + _, ok = md[clientMdKey] + assert.True(s.t, ok, "PingEmpty call must have clients's custom headers in metadata") + return &pb.PingResponse{Value: pingDefaultValue, Counter: 42}, nil +} + +func (s *assertingService) Ping(ctx context.Context, ping *pb.PingRequest) (*pb.PingResponse, error) { + // Send user trailers and headers. + grpc.SendHeader(ctx, metadata.Pairs(serverHeaderMdKey, "I like turtles.")) + grpc.SetTrailer(ctx, metadata.Pairs(serverTrailerMdKey, "I like ending turtles.")) + return &pb.PingResponse{Value: ping.Value, Counter: 42}, nil +} + +func (s *assertingService) PingError(ctx context.Context, ping *pb.PingRequest) (*emptypb.Empty, error) { + return nil, status.Errorf(codes.FailedPrecondition, "Userspace error.") +} + +func (s *assertingService) PingList(ping *pb.PingRequest, stream pb.TestService_PingListServer) error { + // Send user trailers and headers. + stream.SendHeader(metadata.Pairs(serverHeaderMdKey, "I like turtles.")) + for i := 0; i < countListResponses; i++ { + stream.Send(&pb.PingResponse{Value: ping.Value, Counter: int32(i)}) + } + stream.SetTrailer(metadata.Pairs(serverTrailerMdKey, "I like ending turtles.")) + return nil +} + +func (s *assertingService) PingStream(stream pb.TestService_PingStreamServer) error { + stream.SendHeader(metadata.Pairs(serverHeaderMdKey, "I like turtles.")) + counter := int32(0) + for { + ping, err := stream.Recv() + if err == io.EOF { + break + } else if err != nil { + require.NoError(s.t, err, "can't fail reading stream") + return err + } + pong := &pb.PingResponse{Value: ping.Value, Counter: counter} + if err := stream.Send(pong); err != nil { + require.NoError(s.t, err, "can't fail sending back a pong") + } + counter += 1 + } + stream.SetTrailer(metadata.Pairs(serverTrailerMdKey, "I like ending turtles.")) + return nil +} + +// ProxyHappySuite tests the "happy" path of handling: that everything works in absence of connection issues. +type ProxyHappySuite struct { + suite.Suite + + serverListener net.Listener + server *grpc.Server + proxyListener net.Listener + proxy *grpc.Server + serverClientConn *grpc.ClientConn + + client *grpc.ClientConn + testClient pb.TestServiceClient +} + +func (s *ProxyHappySuite) TestPingEmptyCarriesClientMetadata() { + ctx := metadata.NewOutgoingContext(context.Background(), metadata.Pairs(clientMdKey, "true")) + out, err := s.testClient.PingEmpty(ctx, &emptypb.Empty{}) + require.NoError(s.T(), err, "PingEmpty should succeed without errors") + want := &pb.PingResponse{Value: pingDefaultValue, Counter: 42} + require.True(s.T(), proto.Equal(want, out)) +} + +func (s *ProxyHappySuite) TestPingEmpty_StressTest() { + for i := 0; i < 50; i++ { + s.TestPingEmptyCarriesClientMetadata() + } +} + +func (s *ProxyHappySuite) TestPingCarriesServerHeadersAndTrailers() { + headerMd := make(metadata.MD) + trailerMd := make(metadata.MD) + // This is an awkward calling convention... but meh. + out, err := s.testClient.Ping(context.Background(), &pb.PingRequest{Value: "foo"}, grpc.Header(&headerMd), grpc.Trailer(&trailerMd)) + want := &pb.PingResponse{Value: "foo", Counter: 42} + require.NoError(s.T(), err, "Ping should succeed without errors") + require.True(s.T(), proto.Equal(want, out)) + assert.Contains(s.T(), headerMd, serverHeaderMdKey, "server response headers must contain server data") + assert.Len(s.T(), trailerMd, 1, "server response trailers must contain server data") +} + +func (s *ProxyHappySuite) TestPingErrorPropagatesAppError() { + _, err := s.testClient.PingError(context.Background(), &pb.PingRequest{Value: "foo"}) + require.Error(s.T(), err, "PingError should never succeed") + assert.Equal(s.T(), codes.FailedPrecondition, status.Code(err)) + assert.Equal(s.T(), "Userspace error.", status.Convert(err).Message()) +} + +func (s *ProxyHappySuite) TestDirectorErrorIsPropagated() { + // See SetupSuite where the StreamDirector has a special case. + ctx := metadata.NewOutgoingContext(context.Background(), metadata.Pairs(rejectingMdKey, "true")) + _, err := s.testClient.Ping(ctx, &pb.PingRequest{Value: "foo"}) + require.Error(s.T(), err, "Director should reject this RPC") + assert.Equal(s.T(), codes.PermissionDenied, status.Code(err)) + assert.Equal(s.T(), "testing rejection", status.Convert(err).Message()) +} + +func (s *ProxyHappySuite) TestPingStream_FullDuplexWorks() { + stream, err := s.testClient.PingStream(context.Background()) + require.NoError(s.T(), err, "PingStream request should be successful.") + + for i := 0; i < countListResponses; i++ { + ping := &pb.PingRequest{Value: fmt.Sprintf("foo:%d", i)} + require.NoError(s.T(), stream.Send(ping), "sending to PingStream must not fail") + resp, err := stream.Recv() + if err == io.EOF { + break + } + if i == 0 { + // Check that the header arrives before all entries. + headerMd, err := stream.Header() + require.NoError(s.T(), err, "PingStream headers should not error.") + assert.Contains(s.T(), headerMd, serverHeaderMdKey, "PingStream response headers user contain metadata") + } + assert.EqualValues(s.T(), i, resp.Counter, "ping roundtrip must succeed with the correct id") + } + require.NoError(s.T(), stream.CloseSend(), "no error on close send") + _, err = stream.Recv() + require.Equal(s.T(), io.EOF, err, "stream should close with io.EOF, meaining OK") + // Check that the trailer headers are here. + trailerMd := stream.Trailer() + assert.Len(s.T(), trailerMd, 1, "PingList trailer headers user contain metadata") +} + +func (s *ProxyHappySuite) TestPingStream_StressTest() { + for i := 0; i < 50; i++ { + s.TestPingStream_FullDuplexWorks() + } +} + +func (s *ProxyHappySuite) SetupSuite() { + var err error + + s.proxyListener, err = net.Listen("tcp", "127.0.0.1:0") + require.NoError(s.T(), err, "must be able to allocate a port for proxyListener") + s.serverListener, err = net.Listen("tcp", "127.0.0.1:0") + require.NoError(s.T(), err, "must be able to allocate a port for serverListener") + + s.server = grpc.NewServer() + pb.RegisterTestServiceServer(s.server, &assertingService{t: s.T()}) + + // Setup of the proxy's Director. + //lint:ignore SA1019 regression test + s.serverClientConn, err = grpc.Dial(s.serverListener.Addr().String(), grpc.WithInsecure(), grpc.WithCodec(proxy.Codec())) + require.NoError(s.T(), err, "must not error on deferred client Dial") + director := func(ctx context.Context, fullName string) (context.Context, grpc.ClientConnInterface, error) { + md, ok := metadata.FromIncomingContext(ctx) + if ok { + if _, exists := md[rejectingMdKey]; exists { + return ctx, nil, status.Errorf(codes.PermissionDenied, "testing rejection") + } + } + // Explicitly copy the metadata, otherwise the tests will fail. + outCtx := metadata.NewOutgoingContext(ctx, md.Copy()) + return outCtx, s.serverClientConn, nil + } + s.proxy = grpc.NewServer( + //lint:ignore SA1019 regression test + grpc.CustomCodec(proxy.Codec()), + grpc.UnknownServiceHandler(proxy.TransparentHandler(director)), + ) + // Ping handler is handled as an explicit registration and not as a TransparentHandler. + proxy.RegisterService(s.proxy, director, + "mwitkow.testproto.TestService", + "Ping") + + // Start the serving loops. + s.T().Logf("starting grpc.Server at: %v", s.serverListener.Addr().String()) + go func() { + s.server.Serve(s.serverListener) + }() + s.T().Logf("starting grpc.Proxy at: %v", s.proxyListener.Addr().String()) + go func() { + s.proxy.Serve(s.proxyListener) + }() + + dCtx, ccl := context.WithTimeout(context.Background(), time.Second) + defer ccl() + clientConn, err := grpc.DialContext(dCtx, strings.Replace(s.proxyListener.Addr().String(), "127.0.0.1", "localhost", 1), grpc.WithInsecure()) + require.NoError(s.T(), err, "must not error on deferred client Dial") + s.testClient = pb.NewTestServiceClient(clientConn) +} + +func (s *ProxyHappySuite) TearDownSuite() { + if s.client != nil { + s.client.Close() + } + if s.serverClientConn != nil { + s.serverClientConn.Close() + } + // Close all transports so the logs don't get spammy. + time.Sleep(10 * time.Millisecond) + if s.proxy != nil { + s.proxy.Stop() + s.proxyListener.Close() + } + if s.serverListener != nil { + s.server.Stop() + s.serverListener.Close() + } +} + +func TestProxyHappySuite(t *testing.T) { + suite.Run(t, &ProxyHappySuite{}) +} diff --git a/proxy/proxy.go b/proxy/proxy.go new file mode 100644 index 0000000..02e6076 --- /dev/null +++ b/proxy/proxy.go @@ -0,0 +1,33 @@ +// Copyright 2021 Michal Witkowski. All Rights Reserved. +// See LICENSE for licensing terms. + +package proxy + +import ( + "context" + + "google.golang.org/grpc" + "google.golang.org/grpc/metadata" +) + +// NewProxy sets up a simple proxy that forwards all requests to dst. +func NewProxy(dst *grpc.ClientConn, opts ...grpc.ServerOption) *grpc.Server { + opts = append(opts, DefaultProxyOpt(dst)) + // Set up the proxy server and then serve from it like in step one. + return grpc.NewServer(opts...) +} + +// DefaultProxyOpt returns an grpc.UnknownServiceHandler with a DefaultDirector. +func DefaultProxyOpt(cc *grpc.ClientConn) grpc.ServerOption { + return grpc.UnknownServiceHandler(TransparentHandler(DefaultDirector(cc))) +} + +// DefaultDirector returns a very simple forwarding StreamDirector that forwards all +// calls. +func DefaultDirector(cc *grpc.ClientConn) StreamDirector { + return func(ctx context.Context, fullMethodName string) (context.Context, grpc.ClientConnInterface, error) { + md, _ := metadata.FromIncomingContext(ctx) + ctx = metadata.NewOutgoingContext(ctx, md.Copy()) + return ctx, cc, nil + } +} diff --git a/proxy/proxy_test.go b/proxy/proxy_test.go new file mode 100644 index 0000000..d2ce740 --- /dev/null +++ b/proxy/proxy_test.go @@ -0,0 +1,211 @@ +package proxy_test + +import ( + "context" + "flag" + "fmt" + "net" + "testing" + + "google.golang.org/grpc" + "google.golang.org/grpc/metadata" + "google.golang.org/grpc/test/bufconn" + + "go.linka.cloud/grpc-toolkit/proxy" + "go.linka.cloud/grpc-toolkit/proxy/testservice" +) + +var testBackend = flag.String("test-backend", "", "Service providing TestServiceServer") + +// TestIntegrationV1 is a regression test of the proxy. +func TestLegacyBehaviour(t *testing.T) { + // These bufconns are test listeners used to make connections between our + // services. This test actually starts two fully functional grpc services. + proxyBc := bufconn.Listen(10) + + // Setup is a little thorough, but here's the gist of it: + // 1. Create the test backend using testservice.DefaultTestServiceServer + // 2. Create the proxy backend using this package + // 3. Make calls to 1 via 2. + + // 1. + //lint:ignore SA1019 regression test + testCC, err := backendDialer(t, grpc.WithCodec(proxy.Codec())) + if err != nil { + t.Fatal(err) + } + + // 2. + go func() { + // Second, we need to implement the SteamDirector. + directorFn := func(ctx context.Context, fullMethodName string) (context.Context, grpc.ClientConnInterface, error) { + md, _ := metadata.FromIncomingContext(ctx) + outCtx := metadata.NewOutgoingContext(ctx, md.Copy()) + return outCtx, testCC, nil + } + + // Set up the proxy server and then serve from it like in step one. + proxySrv := grpc.NewServer( + //lint:ignore SA1019 regression test + grpc.CustomCodec(proxy.Codec()), // was previously needed for proxy to function. + grpc.UnknownServiceHandler(proxy.TransparentHandler(directorFn)), + ) + // run the proxy backend + go func() { + t.Log("Running proxySrv") + if err := proxySrv.Serve(proxyBc); err != nil { + if err == grpc.ErrServerStopped { + return + } + t.Logf("running proxy server: %v", err) + } + }() + t.Cleanup(func() { + t.Log("Gracefully stopping proxySrv") + proxySrv.GracefulStop() + }) + }() + + // 3. + // Connect to the proxy. We should not need to do anything special here - + // users do not need to know they're talking to a proxy. + proxyCC, err := grpc.Dial( + "bufnet", + grpc.WithInsecure(), + grpc.WithBlock(), + grpc.WithContextDialer(func(ctx context.Context, s string) (net.Conn, error) { + return proxyBc.Dial() + }), + ) + if err != nil { + t.Fatalf("dialing proxy: %v", err) + } + proxyClient := testservice.NewTestServiceClient(proxyCC) + + // 4. Run the tests! + testservice.TestTestServiceServerImpl(t, proxyClient) +} + +func TestNewProxy(t *testing.T) { + proxyBc := bufconn.Listen(10) + + // Setup is a little thorough, but here's the gist of it: + // 1. Create the test backend using testservice.DefaultTestServiceServer + // 2. Create the proxy backend using this package + // 3. Make calls to 1 via 2. + + // 1. + // First, we need to create a client connection to this backend. + testCC, err := backendDialer(t) + if err != nil { + t.Fatal(err) + } + + // 2. + go func() { + t.Helper() + + // First, we need to create a client connection to this backend. + proxySrv := proxy.NewProxy(testCC) + + // run the proxy backend + go func() { + t.Log("Running proxySrv") + if err := proxySrv.Serve(proxyBc); err != nil { + if err == grpc.ErrServerStopped { + return + } + t.Logf("running proxy server: %v", err) + } + }() + t.Cleanup(func() { + t.Log("Gracefully stopping proxySrv") + proxySrv.GracefulStop() + }) + }() + + // 3. + // Connect to the proxy. We should not need to do anything special here - + // users do not need to know they're talking to a proxy. + t.Logf("dialing %s", proxyBc.Addr()) + proxyCC, err := grpc.Dial( + proxyBc.Addr().String(), + grpc.WithInsecure(), + grpc.WithBlock(), + grpc.WithContextDialer(func(ctx context.Context, s string) (net.Conn, error) { + return proxyBc.Dial() + }), + ) + if err != nil { + t.Fatalf("dialing proxy: %v", err) + } + proxyClient := testservice.NewTestServiceClient(proxyCC) + + // 4. Run the tests! + testservice.TestTestServiceServerImpl(t, proxyClient) +} + +// backendDialer dials the testservice.TestServiceServer either by connecting +// to the user-supplied server, or by creating a mock server using bufconn. +func backendDialer(t *testing.T, opts ...grpc.DialOption) (*grpc.ClientConn, error) { + t.Helper() + + if *testBackend != "" { + return backendSvcDialer(t, *testBackend, opts...) + } + + backendBc := bufconn.Listen(10) + // set up the backend using a "real" server over a bufconn + testSrv := grpc.NewServer() + testservice.RegisterTestServiceServer(testSrv, testservice.DefaultTestServiceServer) + + // run the test backend + go func() { + t.Log("Running testSrv") + if err := testSrv.Serve(backendBc); err != nil { + if err == grpc.ErrServerStopped { + return + } + t.Logf("running test server: %v", err) + } + }() + t.Cleanup(func() { + t.Log("Gracefully stopping testSrv") + testSrv.GracefulStop() + }) + + opts = append(opts, + grpc.WithInsecure(), + grpc.WithBlock(), + grpc.WithContextDialer(func(ctx context.Context, s string) (net.Conn, error) { + return backendBc.Dial() + }), + ) + + backendCC, err := grpc.Dial( + "bufnet", + opts..., + ) + if err != nil { + return nil, fmt.Errorf("dialing backend: %v", err) + } + return backendCC, nil +} + +func backendSvcDialer(t *testing.T, addr string, opts ...grpc.DialOption) (*grpc.ClientConn, error) { + opts = append(opts, + grpc.WithInsecure(), + grpc.WithBlock(), + ) + + t.Logf("connecting to %s", addr) + cc, err := grpc.Dial( + addr, + opts..., + ) + if err != nil { + return nil, fmt.Errorf("dialing backend: %v", err) + } + + return cc, nil +} diff --git a/proxy/testservice/Makefile b/proxy/testservice/Makefile new file mode 100644 index 0000000..6812a00 --- /dev/null +++ b/proxy/testservice/Makefile @@ -0,0 +1,9 @@ + +all: test_go + +test_go: test.proto + protoc --go_out=. --go_opt=paths=source_relative \ + --go-grpc_out=. --go-grpc_opt=paths=source_relative \ + test.proto + + diff --git a/proxy/testservice/ping.go b/proxy/testservice/ping.go new file mode 100644 index 0000000..9638781 --- /dev/null +++ b/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) diff --git a/proxy/testservice/server/main.go b/proxy/testservice/server/main.go new file mode 100644 index 0000000..70afa7f --- /dev/null +++ b/proxy/testservice/server/main.go @@ -0,0 +1,54 @@ +package main + +import ( + "flag" + "fmt" + "log" + "net" + "os" + "os/signal" + "syscall" + + "google.golang.org/grpc" + + "go.linka.cloud/grpc-toolkit/proxy/testservice" +) + +var ( + port = flag.Uint("port", 8080, "Port to listen to") +) + +func main() { + srv := grpc.NewServer() + lis, err := net.Listen("tcp", fmt.Sprintf("localhost:%d", *port)) + if err != nil { + panic(err) + } + testservice.RegisterTestServiceServer(srv, testservice.DefaultTestServiceServer) + + errs := make(chan error) + + go func() { + log.Printf("listening on %s", lis.Addr().String()) + errs <- srv.Serve(lis) + }() + + sigs := make(chan os.Signal, 1) + signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM) + + go func() { + sig := <-sigs + log.Printf("shutdown due to %s", sig) + srv.GracefulStop() + }() + + if err := <-errs; err != nil { + log.Println(err) + os.Exit(1) + } + os.Exit(0) +} + +func init() { + flag.Parse() +} diff --git a/proxy/testservice/test.pb.go b/proxy/testservice/test.pb.go new file mode 100644 index 0000000..ff4b0d8 --- /dev/null +++ b/proxy/testservice/test.pb.go @@ -0,0 +1,255 @@ +// Code generated by protoc-gen-go. DO NOT EDIT. +// versions: +// protoc-gen-go v1.25.0-devel +// protoc v3.15.5 +// source: test.proto + +package testservice + +import ( + protoreflect "google.golang.org/protobuf/reflect/protoreflect" + protoimpl "google.golang.org/protobuf/runtime/protoimpl" + emptypb "google.golang.org/protobuf/types/known/emptypb" + reflect "reflect" + sync "sync" +) + +const ( + // Verify that this generated code is sufficiently up-to-date. + _ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion) + // Verify that runtime/protoimpl is sufficiently up-to-date. + _ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20) +) + +type PingRequest struct { + state protoimpl.MessageState + sizeCache protoimpl.SizeCache + unknownFields protoimpl.UnknownFields + + Value string `protobuf:"bytes,1,opt,name=value,proto3" json:"value,omitempty"` +} + +func (x *PingRequest) Reset() { + *x = PingRequest{} + if protoimpl.UnsafeEnabled { + mi := &file_test_proto_msgTypes[0] + ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x)) + ms.StoreMessageInfo(mi) + } +} + +func (x *PingRequest) String() string { + return protoimpl.X.MessageStringOf(x) +} + +func (*PingRequest) ProtoMessage() {} + +func (x *PingRequest) ProtoReflect() protoreflect.Message { + mi := &file_test_proto_msgTypes[0] + if protoimpl.UnsafeEnabled && x != nil { + ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x)) + if ms.LoadMessageInfo() == nil { + ms.StoreMessageInfo(mi) + } + return ms + } + return mi.MessageOf(x) +} + +// Deprecated: Use PingRequest.ProtoReflect.Descriptor instead. +func (*PingRequest) Descriptor() ([]byte, []int) { + return file_test_proto_rawDescGZIP(), []int{0} +} + +func (x *PingRequest) GetValue() string { + if x != nil { + return x.Value + } + return "" +} + +type PingResponse struct { + state protoimpl.MessageState + sizeCache protoimpl.SizeCache + unknownFields protoimpl.UnknownFields + + Value string `protobuf:"bytes,1,opt,name=value,proto3" json:"value,omitempty"` + Counter int32 `protobuf:"varint,2,opt,name=counter,proto3" json:"counter,omitempty"` +} + +func (x *PingResponse) Reset() { + *x = PingResponse{} + if protoimpl.UnsafeEnabled { + mi := &file_test_proto_msgTypes[1] + ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x)) + ms.StoreMessageInfo(mi) + } +} + +func (x *PingResponse) String() string { + return protoimpl.X.MessageStringOf(x) +} + +func (*PingResponse) ProtoMessage() {} + +func (x *PingResponse) ProtoReflect() protoreflect.Message { + mi := &file_test_proto_msgTypes[1] + if protoimpl.UnsafeEnabled && x != nil { + ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x)) + if ms.LoadMessageInfo() == nil { + ms.StoreMessageInfo(mi) + } + return ms + } + return mi.MessageOf(x) +} + +// Deprecated: Use PingResponse.ProtoReflect.Descriptor instead. +func (*PingResponse) Descriptor() ([]byte, []int) { + return file_test_proto_rawDescGZIP(), []int{1} +} + +func (x *PingResponse) GetValue() string { + if x != nil { + return x.Value + } + return "" +} + +func (x *PingResponse) GetCounter() int32 { + if x != nil { + return x.Counter + } + return 0 +} + +var File_test_proto protoreflect.FileDescriptor + +var file_test_proto_rawDesc = []byte{ + 0x0a, 0x0a, 0x74, 0x65, 0x73, 0x74, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x11, 0x6d, 0x77, + 0x69, 0x74, 0x6b, 0x6f, 0x77, 0x2e, 0x74, 0x65, 0x73, 0x74, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x1a, + 0x1b, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, + 0x2f, 0x65, 0x6d, 0x70, 0x74, 0x79, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22, 0x23, 0x0a, 0x0b, + 0x50, 0x69, 0x6e, 0x67, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x12, 0x14, 0x0a, 0x05, 0x76, + 0x61, 0x6c, 0x75, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x05, 0x76, 0x61, 0x6c, 0x75, + 0x65, 0x22, 0x3e, 0x0a, 0x0c, 0x50, 0x69, 0x6e, 0x67, 0x52, 0x65, 0x73, 0x70, 0x6f, 0x6e, 0x73, + 0x65, 0x12, 0x14, 0x0a, 0x05, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x18, 0x01, 0x20, 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+ +var ( + file_test_proto_rawDescOnce sync.Once + file_test_proto_rawDescData = file_test_proto_rawDesc +) + +func file_test_proto_rawDescGZIP() []byte { + file_test_proto_rawDescOnce.Do(func() { + file_test_proto_rawDescData = protoimpl.X.CompressGZIP(file_test_proto_rawDescData) + }) + return file_test_proto_rawDescData +} + +var file_test_proto_msgTypes = make([]protoimpl.MessageInfo, 2) +var file_test_proto_goTypes = []interface{}{ + (*PingRequest)(nil), // 0: mwitkow.testproto.PingRequest + (*PingResponse)(nil), // 1: mwitkow.testproto.PingResponse + (*emptypb.Empty)(nil), // 2: google.protobuf.Empty +} +var file_test_proto_depIdxs = []int32{ + 2, // 0: mwitkow.testproto.TestService.PingEmpty:input_type -> google.protobuf.Empty + 0, // 1: mwitkow.testproto.TestService.Ping:input_type -> mwitkow.testproto.PingRequest + 0, // 2: mwitkow.testproto.TestService.PingError:input_type -> mwitkow.testproto.PingRequest + 0, // 3: mwitkow.testproto.TestService.PingList:input_type -> mwitkow.testproto.PingRequest + 0, // 4: mwitkow.testproto.TestService.PingStream:input_type -> mwitkow.testproto.PingRequest + 1, // 5: mwitkow.testproto.TestService.PingEmpty:output_type -> mwitkow.testproto.PingResponse + 1, // 6: mwitkow.testproto.TestService.Ping:output_type -> mwitkow.testproto.PingResponse + 2, // 7: mwitkow.testproto.TestService.PingError:output_type -> google.protobuf.Empty + 1, // 8: mwitkow.testproto.TestService.PingList:output_type -> mwitkow.testproto.PingResponse + 1, // 9: mwitkow.testproto.TestService.PingStream:output_type -> mwitkow.testproto.PingResponse + 5, // [5:10] is the sub-list for method output_type + 0, // [0:5] is the sub-list for method input_type + 0, // [0:0] is the sub-list for extension type_name + 0, // [0:0] is the sub-list for extension extendee + 0, // [0:0] is the sub-list for field type_name +} + +func init() { file_test_proto_init() } +func file_test_proto_init() { + if File_test_proto != nil { + return + } + if !protoimpl.UnsafeEnabled { + file_test_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} { + switch v := v.(*PingRequest); i { + case 0: + return &v.state + case 1: + return &v.sizeCache + case 2: + return &v.unknownFields + default: + return nil + } + } + file_test_proto_msgTypes[1].Exporter = func(v interface{}, i int) interface{} { + switch v := v.(*PingResponse); i { + case 0: + return &v.state + case 1: + return &v.sizeCache + case 2: + return &v.unknownFields + default: + return nil + } + } + } + type x struct{} + out := protoimpl.TypeBuilder{ + File: protoimpl.DescBuilder{ + GoPackagePath: reflect.TypeOf(x{}).PkgPath(), + RawDescriptor: file_test_proto_rawDesc, + NumEnums: 0, + NumMessages: 2, + NumExtensions: 0, + NumServices: 1, + }, + GoTypes: file_test_proto_goTypes, + DependencyIndexes: file_test_proto_depIdxs, + MessageInfos: file_test_proto_msgTypes, + }.Build() + File_test_proto = out.File + file_test_proto_rawDesc = nil + file_test_proto_goTypes = nil + file_test_proto_depIdxs = nil +} diff --git a/proxy/testservice/test.proto b/proxy/testservice/test.proto new file mode 100644 index 0000000..f7f23b3 --- /dev/null +++ b/proxy/testservice/test.proto @@ -0,0 +1,30 @@ +syntax = "proto3"; + +package mwitkow.testproto; + +option go_package="go.linka.cloud/grpc-toolkit/proxy/testservice"; + +import "google/protobuf/empty.proto"; + +message PingRequest { + string value = 1; +} + +message PingResponse { + string value = 1; + int32 counter = 2; +} + +service TestService { + rpc PingEmpty(google.protobuf.Empty) returns (PingResponse) {} + + rpc Ping(PingRequest) returns (PingResponse) {} + + rpc PingError(PingRequest) returns (google.protobuf.Empty) {} + + rpc PingList(PingRequest) returns (stream PingResponse) {} + + rpc PingStream(stream PingRequest) returns (stream PingResponse) {} + +} + diff --git a/proxy/testservice/test_grpc.pb.go b/proxy/testservice/test_grpc.pb.go new file mode 100644 index 0000000..473c361 --- /dev/null +++ b/proxy/testservice/test_grpc.pb.go @@ -0,0 +1,306 @@ +// Code generated by protoc-gen-go-grpc. DO NOT EDIT. + +package testservice + +import ( + context "context" + grpc "google.golang.org/grpc" + codes "google.golang.org/grpc/codes" + status "google.golang.org/grpc/status" + emptypb "google.golang.org/protobuf/types/known/emptypb" +) + +// This is a compile-time assertion to ensure that this generated file +// is compatible with the grpc package it is being compiled against. +// Requires gRPC-Go v1.32.0 or later. +const _ = grpc.SupportPackageIsVersion7 + +// TestServiceClient is the client API for TestService service. +// +// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream. +type TestServiceClient interface { + PingEmpty(ctx context.Context, in *emptypb.Empty, opts ...grpc.CallOption) (*PingResponse, error) + Ping(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (*PingResponse, error) + PingError(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (*emptypb.Empty, error) + PingList(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (TestService_PingListClient, error) + PingStream(ctx context.Context, opts ...grpc.CallOption) (TestService_PingStreamClient, error) +} + +type testServiceClient struct { + cc grpc.ClientConnInterface +} + +func NewTestServiceClient(cc grpc.ClientConnInterface) TestServiceClient { + return &testServiceClient{cc} +} + +func (c *testServiceClient) PingEmpty(ctx context.Context, in *emptypb.Empty, opts ...grpc.CallOption) (*PingResponse, error) { + out := new(PingResponse) + err := c.cc.Invoke(ctx, "/mwitkow.testproto.TestService/PingEmpty", in, out, opts...) + if err != nil { + return nil, err + } + return out, nil +} + +func (c *testServiceClient) Ping(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (*PingResponse, error) { + out := new(PingResponse) + err := c.cc.Invoke(ctx, "/mwitkow.testproto.TestService/Ping", in, out, opts...) + if err != nil { + return nil, err + } + return out, nil +} + +func (c *testServiceClient) PingError(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (*emptypb.Empty, error) { + out := new(emptypb.Empty) + err := c.cc.Invoke(ctx, "/mwitkow.testproto.TestService/PingError", in, out, opts...) + if err != nil { + return nil, err + } + return out, nil +} + +func (c *testServiceClient) PingList(ctx context.Context, in *PingRequest, opts ...grpc.CallOption) (TestService_PingListClient, error) { + stream, err := c.cc.NewStream(ctx, &TestService_ServiceDesc.Streams[0], "/mwitkow.testproto.TestService/PingList", opts...) + if err != nil { + return nil, err + } + x := &testServicePingListClient{stream} + if err := x.ClientStream.SendMsg(in); err != nil { + return nil, err + } + if err := x.ClientStream.CloseSend(); err != nil { + return nil, err + } + return x, nil +} + +type TestService_PingListClient interface { + Recv() (*PingResponse, error) + grpc.ClientStream +} + +type testServicePingListClient struct { + grpc.ClientStream +} + +func (x *testServicePingListClient) Recv() (*PingResponse, error) { + m := new(PingResponse) + if err := x.ClientStream.RecvMsg(m); err != nil { + return nil, err + } + return m, nil +} + +func (c *testServiceClient) PingStream(ctx context.Context, opts ...grpc.CallOption) (TestService_PingStreamClient, error) { + stream, err := c.cc.NewStream(ctx, &TestService_ServiceDesc.Streams[1], "/mwitkow.testproto.TestService/PingStream", opts...) + if err != nil { + return nil, err + } + x := &testServicePingStreamClient{stream} + return x, nil +} + +type TestService_PingStreamClient interface { + Send(*PingRequest) error + Recv() (*PingResponse, error) + grpc.ClientStream +} + +type testServicePingStreamClient struct { + grpc.ClientStream +} + +func (x *testServicePingStreamClient) Send(m *PingRequest) error { + return x.ClientStream.SendMsg(m) +} + +func (x *testServicePingStreamClient) Recv() (*PingResponse, error) { + m := new(PingResponse) + if err := x.ClientStream.RecvMsg(m); err != nil { + return nil, err + } + return m, nil +} + +// TestServiceServer is the server API for TestService service. +// All implementations must embed UnimplementedTestServiceServer +// for forward compatibility +type TestServiceServer interface { + PingEmpty(context.Context, *emptypb.Empty) (*PingResponse, error) + Ping(context.Context, *PingRequest) (*PingResponse, error) + PingError(context.Context, *PingRequest) (*emptypb.Empty, error) + PingList(*PingRequest, TestService_PingListServer) error + PingStream(TestService_PingStreamServer) error + mustEmbedUnimplementedTestServiceServer() +} + +// UnimplementedTestServiceServer must be embedded to have forward compatible implementations. +type UnimplementedTestServiceServer struct { +} + +func (UnimplementedTestServiceServer) PingEmpty(context.Context, *emptypb.Empty) (*PingResponse, error) { + return nil, status.Errorf(codes.Unimplemented, "method PingEmpty not implemented") +} +func (UnimplementedTestServiceServer) Ping(context.Context, *PingRequest) (*PingResponse, error) { + return nil, status.Errorf(codes.Unimplemented, "method Ping not implemented") +} +func (UnimplementedTestServiceServer) PingError(context.Context, *PingRequest) (*emptypb.Empty, error) { + return nil, status.Errorf(codes.Unimplemented, "method PingError not implemented") +} +func (UnimplementedTestServiceServer) PingList(*PingRequest, TestService_PingListServer) error { + return status.Errorf(codes.Unimplemented, "method PingList not implemented") +} +func (UnimplementedTestServiceServer) PingStream(TestService_PingStreamServer) error { + return status.Errorf(codes.Unimplemented, "method PingStream not implemented") +} +func (UnimplementedTestServiceServer) mustEmbedUnimplementedTestServiceServer() {} + +// UnsafeTestServiceServer may be embedded to opt out of forward compatibility for this service. +// Use of this interface is not recommended, as added methods to TestServiceServer will +// result in compilation errors. +type UnsafeTestServiceServer interface { + mustEmbedUnimplementedTestServiceServer() +} + +func RegisterTestServiceServer(s grpc.ServiceRegistrar, srv TestServiceServer) { + s.RegisterService(&TestService_ServiceDesc, srv) +} + +func _TestService_PingEmpty_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) { + in := new(emptypb.Empty) + if err := dec(in); err != nil { + return nil, err + } + if interceptor == nil { + return srv.(TestServiceServer).PingEmpty(ctx, in) + } + info := &grpc.UnaryServerInfo{ + Server: srv, + FullMethod: "/mwitkow.testproto.TestService/PingEmpty", + } + handler := func(ctx context.Context, req interface{}) (interface{}, error) { + return srv.(TestServiceServer).PingEmpty(ctx, req.(*emptypb.Empty)) + } + return interceptor(ctx, in, info, handler) +} + +func _TestService_Ping_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) { + in := new(PingRequest) + if err := dec(in); err != nil { + return nil, err + } + if interceptor == nil { + return srv.(TestServiceServer).Ping(ctx, in) + } + info := &grpc.UnaryServerInfo{ + Server: srv, + FullMethod: "/mwitkow.testproto.TestService/Ping", + } + handler := func(ctx context.Context, req interface{}) (interface{}, error) { + return srv.(TestServiceServer).Ping(ctx, req.(*PingRequest)) + } + return interceptor(ctx, in, info, handler) +} + +func _TestService_PingError_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) { + in := new(PingRequest) + if err := dec(in); err != nil { + return nil, err + } + if interceptor == nil { + return srv.(TestServiceServer).PingError(ctx, in) + } + info := &grpc.UnaryServerInfo{ + Server: srv, + FullMethod: "/mwitkow.testproto.TestService/PingError", + } + handler := func(ctx context.Context, req interface{}) (interface{}, error) { + return srv.(TestServiceServer).PingError(ctx, req.(*PingRequest)) + } + return interceptor(ctx, in, info, handler) +} + +func _TestService_PingList_Handler(srv interface{}, stream grpc.ServerStream) error { + m := new(PingRequest) + if err := stream.RecvMsg(m); err != nil { + return err + } + return srv.(TestServiceServer).PingList(m, &testServicePingListServer{stream}) +} + +type TestService_PingListServer interface { + Send(*PingResponse) error + grpc.ServerStream +} + +type testServicePingListServer struct { + grpc.ServerStream +} + +func (x *testServicePingListServer) Send(m *PingResponse) error { + return x.ServerStream.SendMsg(m) +} + +func _TestService_PingStream_Handler(srv interface{}, stream grpc.ServerStream) error { + return srv.(TestServiceServer).PingStream(&testServicePingStreamServer{stream}) +} + +type TestService_PingStreamServer interface { + Send(*PingResponse) error + Recv() (*PingRequest, error) + grpc.ServerStream +} + +type testServicePingStreamServer struct { + grpc.ServerStream +} + +func (x *testServicePingStreamServer) Send(m *PingResponse) error { + return x.ServerStream.SendMsg(m) +} + +func (x *testServicePingStreamServer) Recv() (*PingRequest, error) { + m := new(PingRequest) + if err := x.ServerStream.RecvMsg(m); err != nil { + return nil, err + } + return m, nil +} + +// TestService_ServiceDesc is the grpc.ServiceDesc for TestService service. +// It's only intended for direct use with grpc.RegisterService, +// and not to be introspected or modified (even as a copy) +var TestService_ServiceDesc = grpc.ServiceDesc{ + ServiceName: "mwitkow.testproto.TestService", + HandlerType: (*TestServiceServer)(nil), + Methods: []grpc.MethodDesc{ + { + MethodName: "PingEmpty", + Handler: _TestService_PingEmpty_Handler, + }, + { + MethodName: "Ping", + Handler: _TestService_Ping_Handler, + }, + { + MethodName: "PingError", + Handler: _TestService_PingError_Handler, + }, + }, + Streams: []grpc.StreamDesc{ + { + StreamName: "PingList", + Handler: _TestService_PingList_Handler, + ServerStreams: true, + }, + { + StreamName: "PingStream", + Handler: _TestService_PingStream_Handler, + ServerStreams: true, + ClientStreams: true, + }, + }, + Metadata: "test.proto", +} diff --git a/proxy/testservice/testping.go b/proxy/testservice/testping.go new file mode 100644 index 0000000..de5f0a9 --- /dev/null +++ b/proxy/testservice/testping.go @@ -0,0 +1,158 @@ +package testservice + +import ( + "context" + "io" + "reflect" + "testing" + + "google.golang.org/grpc" + "google.golang.org/grpc/metadata" +) + +const ( + returnHeader = "test-client-header" +) + +// TestTestServiceServerImpl can be called to test the underlying TestServiceServer. +func TestTestServiceServerImpl(t *testing.T, client TestServiceClient) { + t.Run("Unary ping", func(t *testing.T) { + want := "hello, world" + hdr := metadata.MD{} + res, err := client.Ping(context.TODO(), &PingRequest{Value: want}, grpc.Header(&hdr)) + if err != nil { + t.Errorf("want no err; got %v", err) + return + } + checkHeaders(t, hdr) + t.Logf("got %v (%d)", res.Value, res.Counter) + if got := res.Value; got != want { + t.Errorf("res.Value = %q; want %q", got, want) + } + }) + + t.Run("Error ping", func(t *testing.T) { + _, err := client.PingError(context.TODO(), &PingRequest{}) + if err == nil { + t.Errorf("want err; got %v", err) + } + }) + + t.Run("Server streaming ping", func(t *testing.T) { + want := "hello, world" + stream, err := client.PingList(context.TODO(), &PingRequest{Value: want}) + if err != nil { + t.Errorf("want no err; got %v", err) + if err := stream.CloseSend(); err != nil { + t.Fatalf("closing send channel: %v", err) + } + return + } + hdr, err := stream.Header() + if err != nil { + t.Errorf("reading headers: %v", err) + } + checkHeaders(t, hdr) + + for { + res, err := stream.Recv() + if err != nil { + if err == io.EOF { + checkTrailers(t, stream.Trailer()) + return + } + t.Errorf("want no err; got %v", err) + return + } + t.Logf("got %v (%d)", res.Value, res.Counter) + if got := res.Value; got != want { + t.Errorf("res.Value = %q; want %q", got, want) + } + } + }) + + t.Run("Bidirectional pinging", func(t *testing.T) { + want := "hello, world" + stream, err := client.PingStream(context.TODO()) + if err != nil { + t.Errorf("want no err; got %v", err) + if err := stream.CloseSend(); err != nil { + t.Fatalf("closing send channel: %v", err) + } + return + } + + d := make(chan struct{}) + go func() { + hdr, err := stream.Header() + if err != nil { + t.Errorf("reading headers: %v", err) + } + checkHeaders(t, hdr) + close(d) + }() + + for i := 0; i < 25; i++ { + if err := stream.Send(&PingRequest{Value: want}); err != nil { + t.Errorf("want no err; got %v", err) + return + } + res, err := stream.Recv() + if err != nil { + t.Errorf("receiving full duplex stream: %w", err) + return + } + t.Logf("got %v (%d)", res.Value, res.Counter) + if got := res.Value; got != want { + t.Errorf("res.Value = %q; want %q", got, want) + } + if got, want := res.Counter, int32(i); got != want { + t.Errorf("res.Counter = %d; want %d", got, want) + } + } + if err := stream.CloseSend(); err != nil { + t.Errorf("closing full duplex stream: %v", err) + } + <-d + }) + + t.Run("Unary ping with headers", func(t *testing.T) { + want := "hello, world" + req := &PingRequest{Value: want} + + ctx := metadata.AppendToOutgoingContext(context.Background(), returnHeader, "I like turtles.") + inHeader := make(metadata.MD) + + res, err := client.Ping(ctx, req, grpc.Header(&inHeader)) + if err != nil { + t.Errorf("want no err; got %v", err) + return + } + t.Logf("got %v (%d)", res.Value, res.Counter) + if !reflect.DeepEqual(inHeader.Get(returnHeader), []string{"I like turtles."}) { + t.Errorf("did not receive correct return headers") + } + }) +} + +func checkTrailers(t *testing.T, md metadata.MD) { + vs := md.Get(PingTrailer) + if want, got := 1, len(vs); want != got { + t.Errorf("trailer %q not present", PingTrailer) + return + } + if want, got := []string{PingTrailerCts}, vs; !reflect.DeepEqual(got, want) { + t.Errorf("trailer mismatch; want %q, got %q", want, got) + } +} + +func checkHeaders(t *testing.T, md metadata.MD) { + vs := md.Get(PingHeader) + if want, got := 1, len(vs); want != got { + t.Errorf("header %q not present", PingHeader) + return + } + if want, got := []string{PingHeaderCts}, vs; !reflect.DeepEqual(got, want) { + t.Errorf("header mismatch; want %q, got %q", want, got) + } +}