8300268: ServerImpl allows too many idle connections when using sun.net.httpserver.maxIdleConnections

Reviewed-by: dfuchs, vtewari, michaelm, jpai
This commit is contained in:
Darragh Clarke 2023-02-09 12:27:57 +00:00 committed by Jaikiran Pai
parent af8973dc50
commit e4d1cff659
3 changed files with 215 additions and 5 deletions
src/jdk.httpserver/share/classes/sun/net/httpserver
test/jdk/com/sun/net/httpserver/bugs/8300268
MaxIdleConnectionsTest.java
jdk.httpserver/sun/net/httpserver

@ -1,5 +1,5 @@
/*
* Copyright (c) 2005, 2022, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2005, 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@ -410,7 +410,7 @@ class ServerImpl {
}
}
responseCompleted (c);
if (t.close || idleConnections.size() >= MAX_IDLE_CONNECTIONS) {
if (t.close) {
c.close();
allConnections.remove (c);
} else {
@ -961,9 +961,24 @@ class ServerImpl {
}
void markIdle(HttpConnection c) {
c.idleStartTime = System.currentTimeMillis();
c.setState(State.IDLE);
idleConnections.add(c);
boolean close = false;
synchronized(idleConnections) {
if (idleConnections.size() >= MAX_IDLE_CONNECTIONS) {
// closing the connection here could block
// instead set boolean and close outside the synchronized block
close = true;
} else {
c.idleStartTime = System.currentTimeMillis();
c.setState(State.IDLE);
idleConnections.add(c);
}
}
if (close) {
c.close();
allConnections.remove(c);
}
}
void markNewlyAccepted(HttpConnection c) {

@ -0,0 +1,145 @@
/*
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/**
* @test
* @bug 8300268
* @library /test/lib
* @modules jdk.httpserver/sun.net.httpserver
* @build jdk.httpserver/sun.net.httpserver.HttpServerAccess MaxIdleConnectionsTest
* @run junit/othervm -Dsun.net.httpserver.maxIdleConnections=4 MaxIdleConnectionsTest
*/
import com.sun.net.httpserver.HttpServer;
import jdk.test.lib.net.URIBuilder;
import sun.net.httpserver.HttpServerAccess;
import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.TestInstance;
import org.junit.jupiter.api.Test;
import java.io.IOException;
import java.io.InputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicInteger;
import static org.junit.jupiter.api.Assertions.assertTrue;
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
public class MaxIdleConnectionsTest {
HttpServer server;
int maxIdleConnections, totalConnections;
CountDownLatch reqFinishedProcessing;
@BeforeAll
void before() throws Exception {
maxIdleConnections = Integer.getInteger("sun.net.httpserver.maxIdleConnections");
totalConnections = maxIdleConnections + 1;
reqFinishedProcessing = new CountDownLatch(totalConnections);
server = startServer(reqFinishedProcessing);
}
@AfterAll
void after() throws Exception {
server.stop(0);
}
// Issue one too many requests and assert that the idle connection pool doesn't
// exceed maxIdleConnections
@Test
public void test() throws Exception {
final int port = server.getAddress().getPort();
final List<Future<Void>> responses = new ArrayList<>();
try (final ExecutorService requestIssuer = Executors.newFixedThreadPool(totalConnections)) {
for (int i = 1; i <= totalConnections; i++) {
URL requestURL = URIBuilder.newBuilder()
.scheme("http")
.loopback()
.port(port)
.path("/MaxIdleConnectionTest/" + i)
.toURL();
final Future<Void> result = requestIssuer.submit(() -> {
System.out.println("Issuing request " + requestURL);
final URLConnection conn = requestURL.openConnection();
try (final InputStream is = conn.getInputStream()) {
is.readAllBytes();
}
return null;
});
responses.add(result);
}
// wait for all the requests to reach each of the handlers
System.out.println("Waiting for all " + totalConnections + " requests to reach" +
" the server side request handler");
reqFinishedProcessing.await();
}
// verify every request got served before checking idle count
for (int i = 0; i < totalConnections; i++) {
responses.get(i).get();
System.out.println("Received successful response for request " + i);
}
// assert that the limit set by maxIdleConnections was not exceeded
int idleConnectionCount = HttpServerAccess.getIdleConnectionCount(server);
System.out.println("count " + idleConnectionCount);
assertTrue(maxIdleConnections >= idleConnectionCount,
String.format("Too many idle connections: %d, limit: %d", idleConnectionCount, maxIdleConnections));
}
// Create HttpServer that will handle requests with multiple threads
private static HttpServer startServer(final CountDownLatch reqFinishedProcessing) throws IOException {
final var bindAddr = new InetSocketAddress(InetAddress.getLoopbackAddress(), 0);
final HttpServer server = HttpServer.create(bindAddr, 0);
final AtomicInteger threadId = new AtomicInteger();
server.setExecutor(Executors.newCachedThreadPool(r -> {
final Thread t = new Thread(r);
t.setName("http-request-handler-" + threadId.incrementAndGet());
t.setDaemon(true);
return t;
}));
server.createContext("/MaxIdleConnectionTest/", (exchange) -> {
System.out.println("Request " + exchange.getRequestURI() + " received");
System.out.println("Sending response for request " + exchange.getRequestURI() + " from " + exchange.getRemoteAddress());
reqFinishedProcessing.countDown();
exchange.sendResponseHeaders(200, 0);
exchange.getResponseBody().close();
});
server.start();
System.out.println("Server started at address " + server.getAddress());
return server;
}
}

@ -0,0 +1,50 @@
/*
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.net.httpserver;
import com.sun.net.httpserver.HttpServer;
import java.lang.reflect.Field;
import java.util.Set;
public class HttpServerAccess {
// Given a HttpServer object get the number of idleConnections it currently has
public static int getIdleConnectionCount(HttpServer server) throws Exception{
// Use reflection to get server object which is HTTPServerImpl
Field serverField = server.getClass().getDeclaredField("server");
serverField.setAccessible(true);
// Get the actual serverImpl class, then get the IdleConnection Field
Object serverImpl = serverField.get(server);
Field idleConnectionField = serverImpl.getClass().getDeclaredField("idleConnections");
idleConnectionField.setAccessible(true);
// Finally get the IdleConnection object which is of type Set<HttpConnection>
Object idleConnectionSet = idleConnectionField.get(serverImpl);
Set<HttpConnection> idleConnectionPool = (Set<HttpConnection>) idleConnectionSet;
return idleConnectionPool.size();
}
}