/*
* 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.cassandra.thrift;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.net.SocketTimeoutException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.concurrent.NamedThreadFactory;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.config.EncryptionOptions.ClientEncryptionOptions;
import org.apache.thrift.TException;
import org.apache.thrift.TProcessor;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.server.TServer;
import org.apache.thrift.server.TThreadPoolServer;
import org.apache.thrift.transport.TSSLTransportFactory;
import org.apache.thrift.transport.TServerSocket;
import org.apache.thrift.transport.TServerTransport;
import org.apache.thrift.transport.TTransport;
import org.apache.thrift.transport.TTransportException;
import org.apache.thrift.transport.TSSLTransportFactory.TSSLTransportParameters;
import com.google.common.util.concurrent.Uninterruptibles;
/**
* Slightly modified version of the Apache Thrift TThreadPoolServer.
* <p/>
* This allows passing an executor so you have more control over the actual
* behaviour of the tasks being run.
* <p/>
* Newer version of Thrift should make this obsolete.
*/
public class CustomTThreadPoolServer extends TServer
{
private static final Logger logger = LoggerFactory.getLogger(CustomTThreadPoolServer.class.getName());
// Executor service for handling client connections
private final ExecutorService executorService;
// Flag for stopping the server
private volatile boolean stopped;
// Server options
private final TThreadPoolServer.Args args;
//Track and Limit the number of connected clients
private final AtomicInteger activeClients = new AtomicInteger(0);
public CustomTThreadPoolServer(TThreadPoolServer.Args args, ExecutorService executorService) {
super(args);
this.executorService = executorService;
this.args = args;
}
public void serve()
{
try
{
serverTransport_.listen();
}
catch (TTransportException ttx)
{
logger.error("Error occurred during listening.", ttx);
return;
}
stopped = false;
while (!stopped)
{
// block until we are under max clients
while (activeClients.get() >= args.maxWorkerThreads)
{
Uninterruptibles.sleepUninterruptibly(100, TimeUnit.MILLISECONDS);
}
try
{
TTransport client = serverTransport_.accept();
activeClients.incrementAndGet();
WorkerProcess wp = new WorkerProcess(client);
executorService.execute(wp);
}
catch (TTransportException ttx)
{
if (ttx.getCause() instanceof SocketTimeoutException) // thrift sucks
continue;
if (!stopped)
{
logger.warn("Transport error occurred during acceptance of message.", ttx);
}
}
if (activeClients.get() >= args.maxWorkerThreads)
logger.warn("Maximum number of clients {} reached", args.maxWorkerThreads);
}
executorService.shutdown();
// Thrift's default shutdown waits for the WorkerProcess threads to complete. We do not,
// because doing that allows a client to hold our shutdown "hostage" by simply not sending
// another message after stop is called (since process will block indefinitely trying to read
// the next meessage header).
//
// The "right" fix would be to update thrift to set a socket timeout on client connections
// (and tolerate unintentional timeouts until stopped is set). But this requires deep
// changes to the code generator, so simply setting these threads to daemon (in our custom
// CleaningThreadPool) and ignoring them after shutdown is good enough.
//
// Remember, our goal on shutdown is not necessarily that each client request we receive
// gets answered first [to do that, you should redirect clients to a different coordinator
// first], but rather (1) to make sure that for each update we ack as successful, we generate
// hints for any non-responsive replicas, and (2) to make sure that we quickly stop
// accepting client connections so shutdown can continue. Not waiting for the WorkerProcess
// threads here accomplishes (2); MessagingService's shutdown method takes care of (1).
//
// See CASSANDRA-3335 and CASSANDRA-3727.
}
public void stop()
{
stopped = true;
serverTransport_.interrupt();
}
private class WorkerProcess implements Runnable
{
/**
* Client that this services.
*/
private TTransport client_;
/**
* Default constructor.
*
* @param client Transport to process
*/
private WorkerProcess(TTransport client)
{
client_ = client;
}
/**
* Loops on processing a client forever
*/
public void run()
{
TProcessor processor = null;
TTransport inputTransport = null;
TTransport outputTransport = null;
TProtocol inputProtocol = null;
TProtocol outputProtocol = null;
SocketAddress socket = null;
try
{
socket = ((TCustomSocket) client_).getSocket().getRemoteSocketAddress();
ThriftSessionManager.instance.setCurrentSocket(socket);
processor = processorFactory_.getProcessor(client_);
inputTransport = inputTransportFactory_.getTransport(client_);
outputTransport = outputTransportFactory_.getTransport(client_);
inputProtocol = inputProtocolFactory_.getProtocol(inputTransport);
outputProtocol = outputProtocolFactory_.getProtocol(outputTransport);
// we check stopped first to make sure we're not supposed to be shutting
// down. this is necessary for graceful shutdown. (but not sufficient,
// since process() can take arbitrarily long waiting for client input.
// See comments at the end of serve().)
while (!stopped && processor.process(inputProtocol, outputProtocol))
{
inputProtocol = inputProtocolFactory_.getProtocol(inputTransport);
outputProtocol = outputProtocolFactory_.getProtocol(outputTransport);
}
}
catch (TTransportException ttx)
{
// Assume the client died and continue silently
// Log at debug to allow debugging of "frame too large" errors (see CASSANDRA-3142).
logger.debug("Thrift transport error occurred during processing of message.", ttx);
}
catch (TException tx)
{
logger.error("Thrift error occurred during processing of message.", tx);
}
catch (Exception x)
{
logger.error("Error occurred during processing of message.", x);
}
finally
{
activeClients.decrementAndGet();
if (socket != null)
ThriftSessionManager.instance.connectionComplete(socket);
}
if (inputTransport != null)
{
inputTransport.close();
}
if (outputTransport != null)
{
outputTransport.close();
}
}
}
public static class Factory implements TServerFactory
{
public TServer buildTServer(Args args)
{
final InetSocketAddress addr = args.addr;
TServerTransport serverTransport;
try
{
final ClientEncryptionOptions clientEnc = DatabaseDescriptor.getClientEncryptionOptions();
if (clientEnc.enabled)
{
logger.info("enabling encrypted thrift connections between client and server");
TSSLTransportParameters params = new TSSLTransportParameters(clientEnc.protocol, clientEnc.cipher_suites);
params.setKeyStore(clientEnc.keystore, clientEnc.keystore_password);
if (clientEnc.require_client_auth)
{
params.setTrustStore(clientEnc.truststore, clientEnc.truststore_password);
params.requireClientAuth(true);
}
TServerSocket sslServer = TSSLTransportFactory.getServerSocket(addr.getPort(), 0, addr.getAddress(), params);
serverTransport = new TCustomServerSocket(sslServer.getServerSocket(), args.keepAlive, args.sendBufferSize, args.recvBufferSize);
}
else
{
serverTransport = new TCustomServerSocket(addr, args.keepAlive, args.sendBufferSize, args.recvBufferSize, args.listenBacklog);
}
}
catch (TTransportException e)
{
throw new RuntimeException(String.format("Unable to create thrift socket to %s:%s", addr.getAddress(), addr.getPort()), e);
}
// ThreadPool Server and will be invocation per connection basis...
TThreadPoolServer.Args serverArgs = new TThreadPoolServer.Args(serverTransport)
.minWorkerThreads(DatabaseDescriptor.getRpcMinThreads())
.maxWorkerThreads(DatabaseDescriptor.getRpcMaxThreads())
.inputTransportFactory(args.inTransportFactory)
.outputTransportFactory(args.outTransportFactory)
.inputProtocolFactory(args.tProtocolFactory)
.outputProtocolFactory(args.tProtocolFactory)
.processor(args.processor);
ExecutorService executorService = new ThreadPoolExecutor(serverArgs.minWorkerThreads,
serverArgs.maxWorkerThreads,
60,
TimeUnit.SECONDS,
new SynchronousQueue<Runnable>(),
new NamedThreadFactory("Thrift"));
return new CustomTThreadPoolServer(serverArgs, executorService);
}
}
}