/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.coyote.http2;
import java.io.IOException;
import java.nio.ByteBuffer;
import jakarta.servlet.AsyncContext;
import jakarta.servlet.ServletOutputStream;
import jakarta.servlet.WriteListener;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.junit.Assert;
import org.junit.Test;
import org.apache.catalina.Context;
import org.apache.catalina.Wrapper;
import org.apache.catalina.startup.Tomcat;
/*
* Based on
* https://bz.apache.org/bugzilla/show_bug.cgi?id=62635
*
* Note: Calling blocking I/O methods (such as flushBuffer()) during
* non-blocking I/O is explicitly called out as illegal in the Servlet
* specification but also goes on to say the behaviour if such a call is
* made is undefined. Which means it is OK if the call works as expected
* (a non-blocking flush is triggered) :).
* If any of these tests fail, that should not block a release since -
* while the specification allows this to work - it doesn't require that
* it does work.
*/
public class TestAsyncFlush extends Http2TestBase {
private static final int BLOCK_SIZE = 1024;
@Test
public void testFlush() throws Exception {
int blockCount = 2048;
int targetSize = BLOCK_SIZE * blockCount;
int totalWindow = ConnectionSettingsBase.DEFAULT_INITIAL_WINDOW_SIZE;
enableHttp2();
Tomcat tomcat = getTomcatInstance();
Context ctxt = getProgrammaticRootContext();
Tomcat.addServlet(ctxt, "simple", new SimpleServlet());
ctxt.addServletMappingDecoded("/simple", "simple");
Wrapper w = Tomcat.addServlet(ctxt, "async", new AsyncFlushServlet(blockCount));
w.setAsyncSupported(true);
ctxt.addServletMappingDecoded("/async", "async");
tomcat.start();
openClientConnection();
doHttpUpgrade();
sendClientPreface();
validateHttp2InitialResponse();
// Reset connection window size after initial response
sendWindowUpdate(0, SimpleServlet.CONTENT_LENGTH);
// Send request
byte[] frameHeader = new byte[9];
ByteBuffer headersPayload = ByteBuffer.allocate(128);
buildGetRequest(frameHeader, headersPayload, null, 3, "/async");
writeFrame(frameHeader, headersPayload);
// Headers
parser.readFrame();
// Body
while (output.getBytesRead() < targetSize) {
if (output.getBytesRead() == totalWindow) {
sendWindowUpdate(3, ConnectionSettingsBase.DEFAULT_INITIAL_WINDOW_SIZE);
sendWindowUpdate(0, ConnectionSettingsBase.DEFAULT_INITIAL_WINDOW_SIZE);
totalWindow += ConnectionSettingsBase.DEFAULT_INITIAL_WINDOW_SIZE;
}
parser.readFrame();
}
// Check that the right number of bytes were received
Assert.assertEquals(targetSize, output.getBytesRead());
}
public static class AsyncFlushServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private final int blockLimit;
public AsyncFlushServlet(int blockLimit) {
this.blockLimit = blockLimit;
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
final AsyncContext asyncContext = request.startAsync();
response.setStatus(HttpServletResponse.SC_OK);
response.setContentType("application/binary");
final ServletOutputStream output = response.getOutputStream();
output.setWriteListener(new WriteListener() {
int blockCount;
byte[] bytes = new byte[BLOCK_SIZE];
@Override
public void onWritePossible() throws IOException {
while (output.isReady()) {
blockCount++;
output.write(bytes);
if (blockCount % 5 == 0) {
response.flushBuffer();
}
if (blockCount == blockLimit) {
asyncContext.complete();
return;
}
}
}
@Override
public void onError(Throwable t) {
t.printStackTrace();
}
});
}
}
}