Function TestWriteSingleFrameCompressed

compress_test.go:71–135

TestWriteSingleFrameCompressed verifies that Conn.Write sends compressed messages in a single frame instead of multiple frames, and that messages below the flateThreshold are sent uncompressed. This is a regression test for https://github.com/coder/websocket/issues/435

(t *testing.T)

// below the flateThreshold are sent uncompressed.
// This is a regression test for https://github.com/coder/websocket/issues/435
func TestWriteSingleFrameCompressed(t *testing.T) {
	t.Parallel()

	var (
		flateThreshold = 64

		largeMsg = []byte(strings.Repeat("hello world ", 100))
		smallMsg = []byte("small message")
	)

	testCases := []struct {
		name     string
		mode     CompressionMode
		msg      []byte
		wantRsv1 bool // true = compressed, false = uncompressed
	}{
		{"ContextTakeover/AboveThreshold", CompressionContextTakeover, largeMsg, true},
		{"NoContextTakeover/AboveThreshold", CompressionNoContextTakeover, largeMsg, true},
		{"ContextTakeover/BelowThreshold", CompressionContextTakeover, smallMsg, false},
		{"NoContextTakeover/BelowThreshold", CompressionNoContextTakeover, smallMsg, false},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()

			clientConn, serverConn := net.Pipe()
			defer clientConn.Close()
			defer serverConn.Close()

			c := newConn(connConfig{
				rwc:            clientConn,
				client:         true,
				copts:          tc.mode.opts(),
				flateThreshold: flateThreshold,
				br:             bufio.NewReader(clientConn),
				bw:             bufio.NewWriterSize(clientConn, 4096),
			})

			ctx, cancel := context.WithTimeout(context.Background(), time.Millisecond*100)
			defer cancel()

			writeDone := make(chan error, 1)
			go func() {
				writeDone <- c.Write(ctx, MessageText, tc.msg)
			}()

			reader := bufio.NewReader(serverConn)
			readBuf := make([]byte, 8)

			h, err := readFrameHeader(reader, readBuf)
			assert.Success(t, err)

			_, err = io.CopyN(io.Discard, reader, h.payloadLength)
			assert.Success(t, err)

			assert.Equal(t, "opcode", opText, h.opcode)
			assert.Equal(t, "rsv1 (compressed)", tc.wantRsv1, h.rsv1)