//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.server;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import org.eclipse.jetty.io.ArrayByteBufferPool;
import org.eclipse.jetty.io.ByteBufferPool;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.util.FutureCallback;
import org.eclipse.jetty.util.StringUtil;
import org.eclipse.jetty.util.annotation.ManagedAttribute;
import org.eclipse.jetty.util.annotation.ManagedObject;
import org.eclipse.jetty.util.component.ContainerLifeCycle;
import org.eclipse.jetty.util.component.Dumpable;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
import org.eclipse.jetty.util.thread.ScheduledExecutorScheduler;
import org.eclipse.jetty.util.thread.Scheduler;
/**
* <p>An abstract implementation of {@link Connector} that provides a {@link ConnectionFactory} mechanism
* for creating {@link Connection} instances for various protocols (HTTP, SSL, SPDY, etc).</p>
*
* <h2>Connector Services</h2>
* The abstract connector manages the dependent services needed by all specific connector instances:
* <ul>
* <li>The {@link Executor} service is used to run all active tasks needed by this connector such as accepting connections
* or handle HTTP requests. The default is to use the {@link Server#getThreadPool()} as an executor.
* </li>
* <li>The {@link Scheduler} service is used to monitor the idle timeouts of all connections and is also made available
* to the connections to time such things as asynchronous request timeouts. The default is to use a new
* {@link ScheduledExecutorScheduler} instance.
* </li>
* <li>The {@link ByteBufferPool} service is made available to all connections to be used to acquire and release
* {@link ByteBuffer} instances from a pool. The default is to use a new {@link ArrayByteBufferPool} instance.
* </li>
* </ul>
* These services are managed as aggregate beans by the {@link ContainerLifeCycle} super class and
* may either be managed or unmanaged beans.
*
* <h2>Connection Factories</h2>
* The connector keeps a collection of {@link ConnectionFactory} instances, each of which are known by their
* protocol name. The protocol name may be a real protocol (eg http/1.1 or spdy/3) or it may be a private name
* that represents a special connection factory. For example, the name "SSL-http/1.1" is used for
* an {@link SslConnectionFactory} that has been instantiated with the {@link HttpConnectionFactory} as it's
* next protocol.
*
* <h4>Configuring Connection Factories</h4>
* The collection of available {@link ConnectionFactory} may be constructor injected or modified with the
* methods {@link #addConnectionFactory(ConnectionFactory)}, {@link #removeConnectionFactory(String)} and
* {@link #setConnectionFactories(Collection)}. Only a single {@link ConnectionFactory} instance may be configured
* per protocol name, so if two factories with the same {@link ConnectionFactory#getProtocol()} are set, then
* the second will replace the first.
* <p>
* The protocol factory used for newly accepted connections is specified by
* the method {@link #setDefaultProtocol(String)} or defaults to the protocol of the first configured factory.
* <p>
* Each Connection factory type is responsible for the configuration of the protocols that it accepts. Thus to
* configure the HTTP protocol, you pass a {@link HttpConfiguration} instance to the {@link HttpConnectionFactory}
* (or the SPDY factories that can also provide HTTP Semantics). Similarly the {@link SslConnectionFactory} is
* configured by passing it a {@link SslContextFactory} and a next protocol name.
*
* <h4>Connection Factory Operation</h4>
* {@link ConnectionFactory}s may simply create a {@link Connection} instance to support a specific
* protocol. For example, the {@link HttpConnectionFactory} will create a {@link HttpConnection} instance
* that can handle http/1.1, http/1.0 and http/0.9.
* <p>
* {@link ConnectionFactory}s may also create a chain of {@link Connection} instances, using other {@link ConnectionFactory} instances.
* For example, the {@link SslConnectionFactory} is configured with a next protocol name, so that once it has accepted
* a connection and created an {@link SslConnection}, it then used the next {@link ConnectionFactory} from the
* connector using the {@link #getConnectionFactory(String)} method, to create a {@link Connection} instance that
* will handle the unecrypted bytes from the {@link SslConnection}. If the next protocol is "http/1.1", then the
* {@link SslConnectionFactory} will have a protocol name of "SSL-http/1.1" and lookup "http/1.1" for the protocol
* to run over the SSL connection.
* <p>
* {@link ConnectionFactory}s may also create temporary {@link Connection} instances that will exchange bytes
* over the connection to determine what is the next protocol to use. For example the NPN protocol is an extension
* of SSL to allow a protocol to be specified during the SSL handshake. NPN is used by the SPDY protocol to
* negotiate the version of SPDY or HTTP that the client and server will speak. Thus to accept a SPDY connection, the
* connector will be configured with {@link ConnectionFactory}s for "SSL-NPN", "NPN", "spdy/3", "spdy/2", "http/1.1"
* with the default protocol being "SSL-NPN". Thus a newly accepted connection uses "SSL-NPN", which specifies a
* SSLConnectionFactory with "NPN" as the next protocol. Thus an SslConnection instance is created chained to an NPNConnection
* instance. The NPN connection then negotiates with the client to determined the next protocol, which could be
* "spdy/3", "spdy/2" or the default of "http/1.1". Once the next protocol is determined, the NPN connection
* calls {@link #getConnectionFactory(String)} to create a connection instance that will replace the NPN connection as
* the connection chained to the SSLConnection.
* <p>
* <h2>Acceptors</h2>
* The connector will execute a number of acceptor tasks to the {@link Exception} service passed to the constructor.
* The acceptor tasks run in a loop while the connector is running and repeatedly call the abstract {@link #accept(int)} method.
* The implementation of the accept method must:
* <nl>
* <li>block waiting for new connections
* <li>accept the connection (eg socket accept)
* <li>perform any configuration of the connection (eg. socket linger times)
* <li>call the {@link #getDefaultConnectionFactory()} {@link ConnectionFactory#newConnection(Connector, org.eclipse.jetty.io.EndPoint)}
* method to create a new Connection instance.
* </nl>
* The default number of acceptor tasks is the minimum of 1 and half the number of available CPUs. Having more acceptors may reduce
* the latency for servers that see a high rate of new connections (eg HTTP/1.0 without keep-alive). Typically the default is
* sufficient for modern persistent protocols (HTTP/1.1, SPDY etc.)
*/
@ManagedObject("Abstract implementation of the Connector Interface")
public abstract class AbstractConnector extends ContainerLifeCycle implements Connector, Dumpable
{
protected final Logger LOG = Log.getLogger(getClass());
// Order is important on server side, so we use a LinkedHashMap
private final Map<String, ConnectionFactory> _factories = new LinkedHashMap<>();
private final Server _server;
private final Executor _executor;
private final Scheduler _scheduler;
private final ByteBufferPool _byteBufferPool;
private final Thread[] _acceptors;
private final Set<EndPoint> _endpoints = Collections.newSetFromMap(new ConcurrentHashMap<EndPoint, Boolean>());
private final Set<EndPoint> _immutableEndPoints = Collections.unmodifiableSet(_endpoints);
private volatile CountDownLatch _stopping;
private long _idleTimeout = 30000;
private String _defaultProtocol;
private ConnectionFactory _defaultConnectionFactory;
private String _name;
private int _acceptorPriorityDelta;
/**
* @param server The server this connector will be added to. Must not be null.
* @param executor An executor for this connector or null to use the servers executor
* @param scheduler A scheduler for this connector or null to either a {@link Scheduler} set as a server bean or if none set, then a new {@link ScheduledExecutorScheduler} instance.
* @param pool A buffer pool for this connector or null to either a {@link ByteBufferPool} set as a server bean or none set, the new {@link ArrayByteBufferPool} instance.
* @param acceptors the number of acceptor threads to use, or -1 for a default value. If 0, then no acceptor threads will be launched and some other mechanism will need to be used to accept new connections.
* @param factories The Connection Factories to use.
*/
public AbstractConnector(
Server server,
Executor executor,
Scheduler scheduler,
ByteBufferPool pool,
int acceptors,
ConnectionFactory... factories)
{
_server=server;
_executor=executor!=null?executor:_server.getThreadPool();
if (scheduler==null)
scheduler=_server.getBean(Scheduler.class);
_scheduler=scheduler!=null?scheduler:new ScheduledExecutorScheduler();
if (pool==null)
pool=_server.getBean(ByteBufferPool.class);
_byteBufferPool = pool!=null?pool:new ArrayByteBufferPool();
addBean(_server,false);
addBean(_executor);
if (executor==null)
unmanage(_executor); // inherited from server
addBean(_scheduler);
addBean(_byteBufferPool);
for (ConnectionFactory factory:factories)
addConnectionFactory(factory);
int cores = Runtime.getRuntime().availableProcessors();
if (acceptors < 0)
acceptors=Math.max(1, Math.min(4,cores/8));
if (acceptors > cores)
LOG.warn("Acceptors should be <= availableProcessors: " + this);
_acceptors = new Thread[acceptors];
}
@Override
public Server getServer()
{
return _server;
}
@Override
public Executor getExecutor()
{
return _executor;
}
@Override
public ByteBufferPool getByteBufferPool()
{
return _byteBufferPool;
}
@Override
@ManagedAttribute("Idle timeout")
public long getIdleTimeout()
{
return _idleTimeout;
}
/**
* <p>Sets the maximum Idle time for a connection, which roughly translates to the {@link Socket#setSoTimeout(int)}
* call, although with NIO implementations other mechanisms may be used to implement the timeout.</p>
* <p>The max idle time is applied:</p>
* <ul>
* <li>When waiting for a new message to be received on a connection</li>
* <li>When waiting for a new message to be sent on a connection</li>
* </ul>
* <p>This value is interpreted as the maximum time between some progress being made on the connection.
* So if a single byte is read or written, then the timeout is reset.</p>
*
* @param idleTimeout the idle timeout
*/
public void setIdleTimeout(long idleTimeout)
{
_idleTimeout = idleTimeout;
}
/**
* @return Returns the number of acceptor threads.
*/
@ManagedAttribute("number of acceptor threads")
public int getAcceptors()
{
return _acceptors.length;
}
@Override
protected void doStart() throws Exception
{
_defaultConnectionFactory = getConnectionFactory(_defaultProtocol);
if(_defaultConnectionFactory==null)
throw new IllegalStateException("No protocol factory for default protocol: "+_defaultProtocol);
super.doStart();
_stopping=new CountDownLatch(_acceptors.length);
for (int i = 0; i < _acceptors.length; i++)
{
Acceptor a = new Acceptor(i);
addBean(a);
getExecutor().execute(a);
}
LOG.info("Started {}", this);
}
protected void interruptAcceptors()
{
synchronized (this)
{
for (Thread thread : _acceptors)
{
if (thread != null)
thread.interrupt();
}
}
}
@Override
public Future<Void> shutdown()
{
return new FutureCallback(true);
}
@Override
protected void doStop() throws Exception
{
// Tell the acceptors we are stopping
interruptAcceptors();
// If we have a stop timeout
long stopTimeout = getStopTimeout();
CountDownLatch stopping=_stopping;
if (stopTimeout > 0 && stopping!=null)
stopping.await(stopTimeout,TimeUnit.MILLISECONDS);
_stopping=null;
super.doStop();
for (Acceptor a : getBeans(Acceptor.class))
removeBean(a);
LOG.info("Stopped {}", this);
}
public void join() throws InterruptedException
{
join(0);
}
public void join(long timeout) throws InterruptedException
{
synchronized (this)
{
for (Thread thread : _acceptors)
if (thread != null)
thread.join(timeout);
}
}
protected abstract void accept(int acceptorID) throws IOException, InterruptedException;
/* ------------------------------------------------------------ */
/**
* @return Is the connector accepting new connections
*/
protected boolean isAccepting()
{
return isRunning();
}
@Override
public ConnectionFactory getConnectionFactory(String protocol)
{
synchronized (_factories)
{
return _factories.get(StringUtil.asciiToLowerCase(protocol));
}
}
@Override
public <T> T getConnectionFactory(Class<T> factoryType)
{
synchronized (_factories)
{
for (ConnectionFactory f : _factories.values())
if (factoryType.isAssignableFrom(f.getClass()))
return (T)f;
return null;
}
}
public void addConnectionFactory(ConnectionFactory factory)
{
synchronized (_factories)
{
String key=StringUtil.asciiToLowerCase(factory.getProtocol());
ConnectionFactory old=_factories.remove(key);
if (old!=null)
{
if (old.getProtocol().equals(_defaultProtocol))
_defaultProtocol=null;
removeBean(old);
if (LOG.isDebugEnabled())
LOG.debug("{} removed {}", this, old);
}
_factories.put(key, factory);
addBean(factory);
if (_defaultProtocol==null)
_defaultProtocol=factory.getProtocol();
if (LOG.isDebugEnabled())
LOG.debug("{} added {}", this, factory);
}
}
public void addIfAbsentConnectionFactory(ConnectionFactory factory)
{
synchronized (_factories)
{
String key=StringUtil.asciiToLowerCase(factory.getProtocol());
if (_factories.containsKey(key))
{
if (LOG.isDebugEnabled())
LOG.debug("{} addIfAbsent ignored {}", this, factory);
}
else
{
_factories.put(key, factory);
addBean(factory);
if (_defaultProtocol==null)
_defaultProtocol=factory.getProtocol();
if (LOG.isDebugEnabled())
LOG.debug("{} addIfAbsent added {}", this, factory);
}
}
}
public ConnectionFactory removeConnectionFactory(String protocol)
{
synchronized (_factories)
{
ConnectionFactory factory= _factories.remove(StringUtil.asciiToLowerCase(protocol));
removeBean(factory);
return factory;
}
}
@Override
public Collection<ConnectionFactory> getConnectionFactories()
{
synchronized (_factories)
{
return _factories.values();
}
}
public void setConnectionFactories(Collection<ConnectionFactory> factories)
{
synchronized (_factories)
{
List<ConnectionFactory> existing = new ArrayList<>(_factories.values());
for (ConnectionFactory factory: existing)
removeConnectionFactory(factory.getProtocol());
for (ConnectionFactory factory: factories)
if (factory!=null)
addConnectionFactory(factory);
}
}
@ManagedAttribute("The priority delta to apply to acceptor threads")
public int getAcceptorPriorityDelta()
{
return _acceptorPriorityDelta;
}
/* ------------------------------------------------------------ */
/** Set the acceptor thread priority delta.
* <p>This allows the acceptor thread to run at a different priority.
* Typically this would be used to lower the priority to give preference
* to handling previously accepted connections rather than accepting
* new connections</p>
* @param acceptorPriorityDelta
*/
public void setAcceptorPriorityDelta(int acceptorPriorityDelta)
{
int old=_acceptorPriorityDelta;
_acceptorPriorityDelta = acceptorPriorityDelta;
if (old!=acceptorPriorityDelta && isStarted())
{
for (Thread thread : _acceptors)
thread.setPriority(Math.max(Thread.MIN_PRIORITY,Math.min(Thread.MAX_PRIORITY,thread.getPriority()-old+acceptorPriorityDelta)));
}
}
@Override
@ManagedAttribute("Protocols supported by this connector")
public List<String> getProtocols()
{
synchronized (_factories)
{
return new ArrayList<>(_factories.keySet());
}
}
public void clearConnectionFactories()
{
synchronized (_factories)
{
_factories.clear();
}
}
@ManagedAttribute("This connector's default protocol")
public String getDefaultProtocol()
{
return _defaultProtocol;
}
public void setDefaultProtocol(String defaultProtocol)
{
_defaultProtocol = StringUtil.asciiToLowerCase(defaultProtocol);
if (isRunning())
_defaultConnectionFactory=getConnectionFactory(_defaultProtocol);
}
@Override
public ConnectionFactory getDefaultConnectionFactory()
{
if (isStarted())
return _defaultConnectionFactory;
return getConnectionFactory(_defaultProtocol);
}
private class Acceptor implements Runnable
{
private final int _acceptor;
private String _name;
private Acceptor(int id)
{
_acceptor = id;
}
@Override
public void run()
{
final Thread thread = Thread.currentThread();
String name=thread.getName();
_name=String.format("%s-acceptor-%d@%x-%s",name,_acceptor,hashCode(),AbstractConnector.this.toString());
thread.setName(_name);
int priority=thread.getPriority();
if (_acceptorPriorityDelta!=0)
thread.setPriority(Math.max(Thread.MIN_PRIORITY,Math.min(Thread.MAX_PRIORITY,priority+_acceptorPriorityDelta)));
synchronized (AbstractConnector.this)
{
_acceptors[_acceptor] = thread;
}
try
{
while (isAccepting())
{
try
{
accept(_acceptor);
}
catch (Throwable e)
{
if (isAccepting())
LOG.warn(e);
else
LOG.ignore(e);
}
}
}
finally
{
thread.setName(name);
if (_acceptorPriorityDelta!=0)
thread.setPriority(priority);
synchronized (AbstractConnector.this)
{
_acceptors[_acceptor] = null;
}
CountDownLatch stopping=_stopping;
if (stopping!=null)
stopping.countDown();
}
}
@Override
public String toString()
{
String name=_name;
if (name==null)
return String.format("acceptor-%d@%x", _acceptor, hashCode());
return name;
}
}
// protected void connectionOpened(Connection connection)
// {
// _stats.connectionOpened();
// connection.onOpen();
// }
//
// protected void connectionClosed(Connection connection)
// {
// connection.onClose();
// long duration = System.currentTimeMillis() - connection.getEndPoint().getCreatedTimeStamp();
// _stats.connectionClosed(duration, connection.getMessagesIn(), connection.getMessagesOut());
// }
//
// public void connectionUpgraded(Connection oldConnection, Connection newConnection)
// {
// oldConnection.onClose();
// _stats.connectionUpgraded(oldConnection.getMessagesIn(), oldConnection.getMessagesOut());
// newConnection.onOpen();
// }
@Override
public Collection<EndPoint> getConnectedEndPoints()
{
return _immutableEndPoints;
}
protected void onEndPointOpened(EndPoint endp)
{
_endpoints.add(endp);
}
protected void onEndPointClosed(EndPoint endp)
{
_endpoints.remove(endp);
}
@Override
public Scheduler getScheduler()
{
return _scheduler;
}
@Override
public String getName()
{
return _name;
}
/* ------------------------------------------------------------ */
/**
* Set a connector name. A context may be configured with
* virtual hosts in the form "@contextname" and will only serve
* requests from the named connector,
* @param name A connector name.
*/
public void setName(String name)
{
_name=name;
}
@Override
public String toString()
{
return String.format("%s@%x{%s,%s}",
_name==null?getClass().getSimpleName():_name,
hashCode(),
getDefaultProtocol(),getProtocols());
}
}