/**
* Copyright (c) 2012-2014, s3auth.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met: 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer. 2) Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution. 3) Neither the name of the s3auth.com nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.s3auth.relay;
import com.jcabi.aspects.Loggable;
import com.jcabi.aspects.Tv;
import com.jcabi.log.Logger;
import com.jcabi.log.VerboseRunnable;
import com.jcabi.log.VerboseThreads;
import com.s3auth.hosts.Hosts;
import java.io.Closeable;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.TimeUnit;
import javax.net.ssl.SSLServerSocketFactory;
import javax.validation.constraints.NotNull;
import lombok.EqualsAndHashCode;
import lombok.ToString;
/**
* HTTP facade (port listener).
*
* <p>The class is instantiated in {@link Main}, once per application run.
*
* <p>The class is mutable and thread-safe.
*
* @author Yegor Bugayenko (yegor@tpc2.com)
* @version $Id$
* @since 0.0.1
* @see Main
* @checkstyle ClassDataAbstractionCoupling (500 lines)
*/
@ToString
@EqualsAndHashCode(of = { "sockets", "server" })
@SuppressWarnings("PMD.DoNotUseThreads")
@Loggable(Loggable.DEBUG)
final class HttpFacade implements Closeable {
/**
* How many threads to use.
*/
private static final int THREADS = Tv.HUNDRED;
/**
* Executor service, with socket openers.
*/
private final transient ScheduledExecutorService frontend =
Executors.newScheduledThreadPool(2, new VerboseThreads("front"));
/**
* Executor service, with consuming threads.
*/
private final transient ScheduledExecutorService backend =
Executors.newScheduledThreadPool(
HttpFacade.THREADS,
new VerboseThreads("back")
);
/**
* Blocking queue of ready-to-be-processed sockets.
*/
private final transient BlockingQueue<Socket> sockets =
new SynchronousQueue<Socket>();
/**
* Server socket.
*/
private final transient ServerSocket server;
/**
* Secured Server socket.
*/
private final transient ServerSocket secured;
/**
* Public ctor.
* @param hosts Hosts
* @param port Port number
* @param sslport SSL port number.
* @throws IOException If can't initialize
*/
HttpFacade(@NotNull final Hosts hosts, final int port, final int sslport)
throws IOException {
this.server = new ServerSocket(port);
this.secured = SSLServerSocketFactory.getDefault()
.createServerSocket(sslport);
final HttpThread thread = new HttpThread(this.sockets, hosts);
final Runnable runnable = new VerboseRunnable(
new HttpFacade.HttpThreadRunnable(thread), true, false
);
for (int idx = 0; idx < HttpFacade.THREADS; ++idx) {
this.backend.scheduleWithFixedDelay(
runnable,
0L, 1L, TimeUnit.NANOSECONDS
);
}
}
/**
* Start listening to the ports.
*/
public void listen() {
this.frontend.scheduleWithFixedDelay(
new VerboseRunnable(
new Runnable() {
@Override
public void run() {
HttpFacade.this.process(HttpFacade.this.server);
}
}
),
0L, 1L, TimeUnit.NANOSECONDS
);
this.frontend.scheduleWithFixedDelay(
new VerboseRunnable(
new Runnable() {
@Override
public void run() {
HttpFacade.this.process(HttpFacade.this.secured);
}
}
),
0L, 1L, TimeUnit.NANOSECONDS
);
}
@Override
public void close() throws IOException {
try {
this.shutdown(this.frontend);
this.shutdown(this.backend);
} catch (final InterruptedException ex) {
Thread.currentThread().interrupt();
throw new IOException(ex);
}
this.server.close();
}
/**
* Process one server socket.
* @param svr The server socket
*/
private void process(final ServerSocket svr) {
final Socket socket;
try {
socket = svr.accept();
} catch (final IOException ex) {
throw new IllegalStateException(ex);
}
try {
if (!this.sockets.offer(socket, Tv.TEN, TimeUnit.SECONDS)) {
HttpFacade.overflow(socket);
Logger.warn(this, "too many open connections");
}
} catch (final InterruptedException ex) {
Thread.currentThread().interrupt();
throw new IllegalStateException(ex);
}
}
/**
* Report overflow problem to the socket and close it.
* @param socket The socket to report to
*/
private static void overflow(final Socket socket) {
try {
new HttpResponse()
.withStatus(HttpURLConnection.HTTP_GATEWAY_TIMEOUT)
.withBody(
String.format(
// @checkstyle LineLength (1 line)
"We're sorry, the site is under high load at the moment (%d open connections), please try again in a few minutes",
HttpFacade.THREADS
)
)
.send(socket);
} catch (final IOException ex) {
throw new IllegalStateException(ex);
}
}
/**
* Shutdown a service.
* @param service The service to shut down
* @throws InterruptedException If fails to shutdown
*/
private void shutdown(final ExecutorService service)
throws InterruptedException {
service.shutdown();
if (service.awaitTermination(Tv.TEN, TimeUnit.SECONDS)) {
Logger.info(this, "#shutdown(): succeeded");
} else {
Logger.warn(this, "#shutdown(): failed");
service.shutdownNow();
if (service.awaitTermination(Tv.TEN, TimeUnit.SECONDS)) {
Logger.info(this, "#shutdown(): shutdownNow() succeeded");
} else {
Logger.error(this, "#shutdown(): failed to stop threads");
}
}
}
/**
* Dispatcher of HttpThread.
*/
private static final class HttpThreadRunnable implements Runnable {
/**
* The thread to run.
*/
private final transient HttpThread thread;
/**
* Constructor.
* @param thrd The HttpThread
*/
HttpThreadRunnable(final HttpThread thrd) {
this.thread = thrd;
}
@Override
public void run() {
try {
this.thread.dispatch();
} catch (final InterruptedException ex) {
Thread.currentThread().interrupt();
Logger.warn(this, "%s", ex);
}
}
}
}