/*
* Copyright (C) 2012 Facebook, Inc.
*
* Licensed 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 com.facebook.swift.service;
import com.facebook.swift.codec.ThriftCodecManager;
import com.facebook.swift.service.metadata.ThriftMethodMetadata;
import com.facebook.swift.service.metadata.ThriftServiceMetadata;
import com.google.common.base.Preconditions;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.Multimap;
import org.apache.thrift.TApplicationException;
import org.apache.thrift.TException;
import org.apache.thrift.TProcessor;
import org.apache.thrift.protocol.TMessage;
import org.apache.thrift.protocol.TMessageType;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.protocol.TProtocolUtil;
import org.apache.thrift.protocol.TType;
import java.util.List;
import java.util.Map;
import javax.annotation.concurrent.ThreadSafe;
import static org.apache.thrift.TApplicationException.INVALID_MESSAGE_TYPE;
import static org.apache.thrift.TApplicationException.UNKNOWN_METHOD;
/**
* Example TProcessor that wraps a Thrift service. This should only be considered an example, and
* is not production ready. For example, this class makes assumptions about the thrift id of
* method parameters, and does not support Thrift exceptions properly.
*/
@ThreadSafe
public class ThriftServiceProcessor implements TProcessor
{
private final Map<String, ThriftMethodProcessor> methods;
private final Multimap<String, ThriftMethodStats> serviceStats;
/**
* @param services the services to expose; services must be thread safe
*/
public ThriftServiceProcessor(ThriftCodecManager codecManager, Object... services)
{
this(codecManager, ImmutableList.copyOf(services));
}
public ThriftServiceProcessor(ThriftCodecManager codecManager, List<Object> services)
{
Preconditions.checkNotNull(codecManager, "codecManager is null");
Preconditions.checkNotNull(services, "service is null");
Preconditions.checkArgument(!services.isEmpty(), "services is empty");
// NOTE: ImmutableMap enforces that we don't have duplicate method names
ImmutableMap.Builder<String, ThriftMethodProcessor> processorBuilder = ImmutableMap.builder();
ImmutableMultimap.Builder<String, ThriftMethodStats> statsBuilder = ImmutableMultimap.builder();
for (Object service : services) {
ThriftServiceMetadata serviceMetadata = new ThriftServiceMetadata(service.getClass(), codecManager.getCatalog());
for (ThriftMethodMetadata methodMetadata : serviceMetadata.getMethods().values()) {
ThriftMethodProcessor methodProcessor = new ThriftMethodProcessor(service, methodMetadata, codecManager);
processorBuilder.put(methodMetadata.getName(), methodProcessor);
statsBuilder.put(serviceMetadata.getName(), methodProcessor.getStats());
}
}
methods = processorBuilder.build();
serviceStats = statsBuilder.build();
}
public Map<String, ThriftMethodProcessor> getMethods()
{
return methods;
}
public Multimap<String, ThriftMethodStats> getServiceStats()
{
return serviceStats;
}
@Override
@SuppressWarnings("PMD.EmptyCatchBlock")
public boolean process(TProtocol in, TProtocol out)
throws TException
{
TMessage message = in.readMessageBegin();
String methodName = message.name;
int sequenceId = message.seqid;
try {
// lookup method
ThriftMethodProcessor method = methods.get(methodName);
if (method == null) {
TProtocolUtil.skip(in, TType.STRUCT);
throw new TApplicationException(UNKNOWN_METHOD, "Invalid method name: '" + methodName + "'");
}
switch (message.type) {
case TMessageType.CALL:
case TMessageType.ONEWAY:
// Ideally we'd check the message type here to make the presence/absence of
// the "oneway" keyword annotating the method matches the message type.
// Unfortunately most clients send both one-way and two-way messages as CALL
// message type instead of using ONEWAY message type, and servers ignore the
// difference.
break;
default:
throw new TApplicationException(INVALID_MESSAGE_TYPE,
"Received invalid message type " + message.type + " from client");
}
// invoke method
method.process(in, out, sequenceId);
return true;
}
catch (Exception e) {
// Other exceptions are not recoverable. The input or output streams may be corrupt.
Throwables.propagateIfInstanceOf(e, TException.class);
throw new TException(e);
}
finally {
try {
in.readMessageEnd();
}
catch (TException ignore) {
}
}
}
}