snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

test/stream_cleanup_test.go

@@ -0,0 +1,139 @@
+/*
+ *
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package test
+
+import (
+	"context"
+	"io"
+	"testing"
+	"time"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/stubserver"
+	"google.golang.org/grpc/status"
+
+	testgrpc "google.golang.org/grpc/interop/grpc_testing"
+	testpb "google.golang.org/grpc/interop/grpc_testing"
+)
+
+func (s) TestStreamCleanup(t *testing.T) {
+	const initialWindowSize uint = 70 * 1024 // Must be higher than default 64K, ignored otherwise
+	const bodySize = 2 * initialWindowSize   // Something that is not going to fit in a single window
+	const callRecvMsgSize uint = 1           // The maximum message size the client can receive
+
+	ss := &stubserver.StubServer{
+		UnaryCallF: func(context.Context, *testpb.SimpleRequest) (*testpb.SimpleResponse, error) {
+			return &testpb.SimpleResponse{Payload: &testpb.Payload{
+				Body: make([]byte, bodySize),
+			}}, nil
+		},
+		EmptyCallF: func(context.Context, *testpb.Empty) (*testpb.Empty, error) {
+			return &testpb.Empty{}, nil
+		},
+	}
+	if err := ss.Start(nil, grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(int(callRecvMsgSize))), grpc.WithInitialWindowSize(int32(initialWindowSize))); err != nil {
+		t.Fatalf("Error starting endpoint server: %v", err)
+	}
+	defer ss.Stop()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+	if _, err := ss.Client.UnaryCall(ctx, &testpb.SimpleRequest{}); status.Code(err) != codes.ResourceExhausted {
+		t.Fatalf("should fail with ResourceExhausted, message's body size: %v, maximum message size the client can receive: %v", bodySize, callRecvMsgSize)
+	}
+	if _, err := ss.Client.EmptyCall(ctx, &testpb.Empty{}); err != nil {
+		t.Fatalf("should succeed, err: %v", err)
+	}
+}
+
+func (s) TestStreamCleanupAfterSendStatus(t *testing.T) {
+	const initialWindowSize uint = 70 * 1024 // Must be higher than default 64K, ignored otherwise
+	const bodySize = 2 * initialWindowSize   // Something that is not going to fit in a single window
+
+	serverReturnedStatus := make(chan struct{})
+
+	ss := &stubserver.StubServer{
+		FullDuplexCallF: func(stream testgrpc.TestService_FullDuplexCallServer) error {
+			defer func() {
+				close(serverReturnedStatus)
+			}()
+			return stream.Send(&testpb.StreamingOutputCallResponse{
+				Payload: &testpb.Payload{
+					Body: make([]byte, bodySize),
+				},
+			})
+		},
+	}
+	if err := ss.Start(nil, grpc.WithInitialWindowSize(int32(initialWindowSize))); err != nil {
+		t.Fatalf("Error starting endpoint server: %v", err)
+	}
+	defer ss.Stop()
+
+	// This test makes sure we don't delete stream from server transport's
+	// activeStreams list too aggressively.
+
+	// 1. Make a long living stream RPC. So server's activeStream list is not
+	// empty.
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+	stream, err := ss.Client.FullDuplexCall(ctx)
+	if err != nil {
+		t.Fatalf("FullDuplexCall= _, %v; want _, <nil>", err)
+	}
+
+	// 2. Wait for service handler to return status.
+	//
+	// This will trigger a stream cleanup code, which will eventually remove
+	// this stream from activeStream.
+	//
+	// But the stream removal won't happen because it's supposed to be done
+	// after the status is sent by loopyWriter, and the status send is blocked
+	// by flow control.
+	<-serverReturnedStatus
+
+	// 3. GracefulStop (besides sending goaway) checks the number of
+	// activeStreams.
+	//
+	// It will close the connection if there's no active streams. This won't
+	// happen because of the pending stream. But if there's a bug in stream
+	// cleanup that causes stream to be removed too aggressively, the connection
+	// will be closed and the stream will be broken.
+	gracefulStopDone := make(chan struct{})
+	go func() {
+		defer close(gracefulStopDone)
+		ss.S.GracefulStop()
+	}()
+
+	// 4. Make sure the stream is not broken.
+	if _, err := stream.Recv(); err != nil {
+		t.Fatalf("stream.Recv() = _, %v, want _, <nil>", err)
+	}
+	if _, err := stream.Recv(); err != io.EOF {
+		t.Fatalf("stream.Recv() = _, %v, want _, io.EOF", err)
+	}
+
+	timer := time.NewTimer(time.Second)
+	select {
+	case <-gracefulStopDone:
+		timer.Stop()
+	case <-timer.C:
+		t.Fatalf("s.GracefulStop() didn't finish within 1 second after the last RPC")
+	}
+}