testSettingsAckIsSentBeforeUsingFlowControl() — netty Function Reference

Source Code

codec-http2/src/test/java/io/netty/handler/codec/http2/Http2ConnectionRoundtripTest.java lines 352–439

    @Test
    public void testSettingsAckIsSentBeforeUsingFlowControl() throws Exception {
        final CountDownLatch serverSettingsAckLatch1 = new CountDownLatch(1);
        final CountDownLatch serverSettingsAckLatch2 = new CountDownLatch(2);
        final CountDownLatch serverDataLatch = new CountDownLatch(1);
        final CountDownLatch clientWriteDataLatch = new CountDownLatch(1);
        final byte[] data = new byte[] {1, 2, 3, 4, 5};
        final ByteArrayOutputStream out = new ByteArrayOutputStream(data.length);

        doAnswer(new Answer<Void>() {
            @Override
            public Void answer(InvocationOnMock invocationOnMock) throws Throwable {
                serverSettingsAckLatch1.countDown();
                serverSettingsAckLatch2.countDown();
                return null;
            }
        }).when(serverListener).onSettingsAckRead(any(ChannelHandlerContext.class));
        doAnswer(new Answer<Integer>() {
            @Override
            public Integer answer(InvocationOnMock in) throws Throwable {
                ByteBuf buf = (ByteBuf) in.getArguments()[2];
                int padding = (Integer) in.getArguments()[3];
                int processedBytes = buf.readableBytes() + padding;

                buf.readBytes(out, buf.readableBytes());
                serverDataLatch.countDown();
                return processedBytes;
            }
        }).when(serverListener).onDataRead(any(ChannelHandlerContext.class), eq(3),
                any(ByteBuf.class), eq(0), anyBoolean());

        bootstrapEnv(1, 1, 2, 1);

        final Http2Headers headers = dummyHeaders();

        // The server initially reduces the connection flow control window to 0.
        runInChannel(serverConnectedChannel, new Http2Runnable() {
            @Override
            public void run() throws Http2Exception {
                http2Server.encoder().writeSettings(serverCtx(),
                        new Http2Settings().copyFrom(http2Server.decoder().localSettings())
                                .initialWindowSize(0),
                        serverNewPromise());
                http2Server.flush(serverCtx());
            }
        });

        assertTrue(serverSettingsAckLatch1.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));

        // The client should now attempt to send data, but the window size is 0 so it will be queued in the flow
        // controller.
        runInChannel(clientChannel, new Http2Runnable() {
            @Override
            public void run() throws Http2Exception {
                http2Client.encoder().writeHeaders(ctx(), 3, headers, 0, (short) 16, false, 0, false,
                        newPromise());
                http2Client.encoder().writeData(ctx(), 3, Unpooled.wrappedBuffer(data), 0, true, newPromise());
                http2Client.flush(ctx());
                clientWriteDataLatch.countDown();
            }
        });

        assertTrue(clientWriteDataLatch.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));

        // Now the server opens up the connection window to allow the client to send the pending data.
        runInChannel(serverConnectedChannel, new Http2Runnable() {
            @Override
            public void run() throws Http2Exception {
                http2Server.encoder().writeSettings(serverCtx(),
                        new Http2Settings().copyFrom(http2Server.decoder().localSettings())
                                .initialWindowSize(data.length),
                        serverNewPromise());
                http2Server.flush(serverCtx());
            }
        });

        assertTrue(serverSettingsAckLatch2.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));
        assertTrue(serverDataLatch.await(DEFAULT_AWAIT_TIMEOUT_SECONDS, SECONDS));
        assertArrayEquals(data, out.toByteArray());

        // Verify that no errors have been received.