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

encoding/compressor_test.go

@@ -0,0 +1,281 @@
+/*
+ *
+ * Copyright 2025 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 encoding_test
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"sync/atomic"
+	"testing"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/encoding"
+	"google.golang.org/grpc/encoding/internal"
+	"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"
+
+	_ "google.golang.org/grpc/encoding/gzip"
+)
+
+// wrapCompressor is a wrapper of encoding.Compressor which maintains count of
+// Compressor method invokes.
+type wrapCompressor struct {
+	encoding.Compressor
+	compressInvokes int32
+}
+
+func (wc *wrapCompressor) Compress(w io.Writer) (io.WriteCloser, error) {
+	atomic.AddInt32(&wc.compressInvokes, 1)
+	return wc.Compressor.Compress(w)
+}
+
+func setupGzipWrapCompressor(t *testing.T) *wrapCompressor {
+	regFn := internal.RegisterCompressorForTesting.(func(encoding.Compressor) func())
+	c := &wrapCompressor{Compressor: encoding.GetCompressor("gzip")}
+	unreg := regFn(c)
+	t.Cleanup(unreg)
+	return c
+}
+
+func (s) TestSetSendCompressorSuccess(t *testing.T) {
+	for _, tt := range []struct {
+		name                string
+		desc                string
+		payload             *testpb.Payload
+		dialOpts            []grpc.DialOption
+		resCompressor       string
+		wantCompressInvokes int32
+	}{
+		{
+			name:                "identity_request_and_gzip_response",
+			desc:                "request is uncompressed and response is gzip compressed",
+			payload:             &testpb.Payload{Body: []byte("payload")},
+			resCompressor:       "gzip",
+			wantCompressInvokes: 1,
+		},
+		{
+			name:                "identity_request_and_empty_response",
+			desc:                "request is uncompressed and response is gzip compressed",
+			payload:             nil,
+			resCompressor:       "gzip",
+			wantCompressInvokes: 0,
+		},
+		{
+			name:          "gzip_request_and_identity_response",
+			desc:          "request is gzip compressed and response is uncompressed with identity",
+			payload:       &testpb.Payload{Body: []byte("payload")},
+			resCompressor: "identity",
+			dialOpts: []grpc.DialOption{
+				// Use WithCompressor instead of UseCompressor to avoid counting
+				// the client's compressor usage.
+				grpc.WithCompressor(grpc.NewGZIPCompressor()),
+			},
+			wantCompressInvokes: 0,
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Run("unary", func(t *testing.T) {
+				testUnarySetSendCompressorSuccess(t, tt.payload, tt.resCompressor, tt.wantCompressInvokes, tt.dialOpts)
+			})
+
+			t.Run("stream", func(t *testing.T) {
+				testStreamSetSendCompressorSuccess(t, tt.payload, tt.resCompressor, tt.wantCompressInvokes, tt.dialOpts)
+			})
+		})
+	}
+}
+
+func testUnarySetSendCompressorSuccess(t *testing.T, payload *testpb.Payload, resCompressor string, wantCompressInvokes int32, dialOpts []grpc.DialOption) {
+	wc := setupGzipWrapCompressor(t)
+	ss := &stubserver.StubServer{
+		UnaryCallF: func(ctx context.Context, _ *testpb.SimpleRequest) (*testpb.SimpleResponse, error) {
+			if err := grpc.SetSendCompressor(ctx, resCompressor); err != nil {
+				return nil, err
+			}
+			return &testpb.SimpleResponse{
+				Payload: payload,
+			}, nil
+		},
+	}
+	if err := ss.Start(nil, dialOpts...); 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{}); err != nil {
+		t.Fatalf("Unexpected unary call error, got: %v, want: nil", err)
+	}
+
+	compressInvokes := atomic.LoadInt32(&wc.compressInvokes)
+	if compressInvokes != wantCompressInvokes {
+		t.Fatalf("Unexpected compress invokes, got:%d, want: %d", compressInvokes, wantCompressInvokes)
+	}
+}
+
+func testStreamSetSendCompressorSuccess(t *testing.T, payload *testpb.Payload, resCompressor string, wantCompressInvokes int32, dialOpts []grpc.DialOption) {
+	wc := setupGzipWrapCompressor(t)
+	ss := &stubserver.StubServer{
+		FullDuplexCallF: func(stream testgrpc.TestService_FullDuplexCallServer) error {
+			if _, err := stream.Recv(); err != nil {
+				return err
+			}
+
+			if err := grpc.SetSendCompressor(stream.Context(), resCompressor); err != nil {
+				return err
+			}
+
+			return stream.Send(&testpb.StreamingOutputCallResponse{
+				Payload: payload,
+			})
+		},
+	}
+	if err := ss.Start(nil, dialOpts...); err != nil {
+		t.Fatalf("Error starting endpoint server: %v", err)
+	}
+	defer ss.Stop()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	s, err := ss.Client.FullDuplexCall(ctx)
+	if err != nil {
+		t.Fatalf("Unexpected full duplex call error, got: %v, want: nil", err)
+	}
+
+	if err := s.Send(&testpb.StreamingOutputCallRequest{}); err != nil {
+		t.Fatalf("Unexpected full duplex call send error, got: %v, want: nil", err)
+	}
+
+	if _, err := s.Recv(); err != nil {
+		t.Fatalf("Unexpected full duplex recv error, got: %v, want: nil", err)
+	}
+
+	compressInvokes := atomic.LoadInt32(&wc.compressInvokes)
+	if compressInvokes != wantCompressInvokes {
+		t.Fatalf("Unexpected compress invokes, got:%d, want: %d", compressInvokes, wantCompressInvokes)
+	}
+}
+
+// fakeCompressor returns a messages of a configured size, irrespective of the
+// input.
+type fakeCompressor struct {
+	decompressedMessageSize int
+}
+
+func (f *fakeCompressor) Compress(w io.Writer) (io.WriteCloser, error) {
+	return nopWriteCloser{w}, nil
+}
+
+func (f *fakeCompressor) Decompress(io.Reader) (io.Reader, error) {
+	return bytes.NewReader(make([]byte, f.decompressedMessageSize)), nil
+}
+
+func (f *fakeCompressor) Name() string {
+	// Use the name of an existing compressor to avoid interactions with other
+	// tests since compressors can't be un-registered.
+	return "fake"
+}
+
+type nopWriteCloser struct {
+	io.Writer
+}
+
+func (nopWriteCloser) Close() error {
+	return nil
+}
+
+// TestDecompressionExceedsMaxMessageSize uses a fake compressor that produces
+// messages of size 100 bytes on decompression. A server is started with the
+// max receive message size restricted to 99 bytes. The test verifies that the
+// client receives a ResourceExhausted response from the server.
+func (s) TestDecompressionExceedsMaxMessageSize(t *testing.T) {
+	const messageLen = 100
+	regFn := internal.RegisterCompressorForTesting.(func(encoding.Compressor) func())
+	compressor := &fakeCompressor{decompressedMessageSize: messageLen}
+	unreg := regFn(compressor)
+	defer unreg()
+	ss := &stubserver.StubServer{
+		UnaryCallF: func(context.Context, *testpb.SimpleRequest) (*testpb.SimpleResponse, error) {
+			return &testpb.SimpleResponse{}, nil
+		},
+	}
+	if err := ss.Start([]grpc.ServerOption{grpc.MaxRecvMsgSize(messageLen - 1)}); err != nil {
+		t.Fatalf("Error starting endpoint server: %v", err)
+	}
+	defer ss.Stop()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	req := &testpb.SimpleRequest{Payload: &testpb.Payload{}}
+	_, err := ss.Client.UnaryCall(ctx, req, grpc.UseCompressor(compressor.Name()))
+	if got, want := status.Code(err), codes.ResourceExhausted; got != want {
+		t.Errorf("Client.UnaryCall(%+v) returned status %v, want %v", req, got, want)
+	}
+}
+
+// Test verifies that decompression failures (after stream establishment) are
+// handled gracefully without duplicate status writes.
+func (s) TestStreamingDecompressionExceedsMaxMessageSize(t *testing.T) {
+	const messageLen = 100
+	regFn := internal.RegisterCompressorForTesting.(func(encoding.Compressor) func())
+	compressor := &fakeCompressor{decompressedMessageSize: messageLen}
+	unreg := regFn(compressor)
+	defer unreg()
+
+	ss := &stubserver.StubServer{
+		FullDuplexCallF: func(stream testgrpc.TestService_FullDuplexCallServer) error {
+			for {
+				if _, err := stream.Recv(); err != nil {
+					return err
+				}
+			}
+		},
+	}
+	if err := ss.Start([]grpc.ServerOption{grpc.MaxRecvMsgSize(messageLen - 1)}); err != nil {
+		t.Fatalf("Error starting endpoint server: %v", err)
+	}
+	defer ss.Stop()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+	stream, err := ss.Client.FullDuplexCall(ctx, grpc.UseCompressor(compressor.Name()))
+	if err != nil {
+		t.Fatalf("FullDuplexCall failed: %v", err)
+	}
+
+	// Send message that will result in decompression failure on the server
+	// because it exceeds the max message size.
+	if err := stream.Send(&testpb.StreamingOutputCallRequest{Payload: &testpb.Payload{Body: []byte("payload")}}); err != nil {
+		t.Fatalf("Send() failed: %v", err)
+	}
+
+	// We expect the stream to fail with ResourceExhausted on Recv.
+	if _, err = stream.Recv(); status.Code(err) != codes.ResourceExhausted {
+		t.Fatalf("stream.Recv() returned status %v, want %v", status.Code(err), codes.ResourceExhausted)
+	}
+}