/*
* Copyright 2013 The Netty Project
*
* The Netty Project 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 com.couchbase.client.deps.io.netty.handler.codec.memcache.binary;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.CombinedChannelDuplexHandler;
import io.netty.handler.codec.PrematureChannelClosureException;
import com.couchbase.client.deps.io.netty.handler.codec.memcache.LastMemcacheContent;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
/**
* The client codec that combines the proper encoder and decoder.
* <p/>
* Use this codec if you want to implement a memcache client that speaks the binary protocol. It
* combines both the {@link BinaryMemcacheResponseDecoder} and the {@link BinaryMemcacheRequestEncoder}.
* <p/>
* Optionally, it counts the number of outstanding responses and raises an exception if - on connection
* close - the list is not 0 (this is turned off by default). You can also define a chunk size for the
* content, which defaults to 8192. This chunk size is the maximum, so if smaller chunks arrive they
* will be passed up the pipeline and not queued up to the chunk size.
*/
public final class BinaryMemcacheClientCodec extends CombinedChannelDuplexHandler<BinaryMemcacheClientCodec.Decoder, BinaryMemcacheClientCodec.Encoder> {
private final boolean failOnMissingResponse;
private final AtomicLong requestResponseCounter = new AtomicLong();
/**
* Create a new {@link BinaryMemcacheClientCodec} with the default settings applied.
*/
public BinaryMemcacheClientCodec() {
this(AbstractBinaryMemcacheDecoder.DEFAULT_MAX_CHUNK_SIZE);
}
/**
* Create a new {@link BinaryMemcacheClientCodec} and set a custom chunk size.
*
* @param decodeChunkSize the maximum chunk size.
*/
public BinaryMemcacheClientCodec(int decodeChunkSize) {
this(decodeChunkSize, false);
}
/**
* Create a new {@link BinaryMemcacheClientCodec} with custom settings.
*
* @param decodeChunkSize the maximum chunk size.
* @param failOnMissingResponse report if after close there are outstanding requests.
*/
public BinaryMemcacheClientCodec(int decodeChunkSize, boolean failOnMissingResponse) {
this.failOnMissingResponse = failOnMissingResponse;
init(new Decoder(decodeChunkSize), new Encoder());
}
final class Encoder extends BinaryMemcacheRequestEncoder {
@Override
protected void encode(ChannelHandlerContext ctx, Object msg, List<Object> out) throws Exception {
super.encode(ctx, msg, out);
if (failOnMissingResponse && msg instanceof LastMemcacheContent) {
requestResponseCounter.incrementAndGet();
}
}
}
final class Decoder extends BinaryMemcacheResponseDecoder {
Decoder(int chunkSize) {
super(chunkSize);
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
int oldSize = out.size();
super.decode(ctx, in, out);
if (failOnMissingResponse) {
final int size = out.size();
for (int i = oldSize; i < size; i ++) {
Object msg = out.get(i);
if (msg instanceof LastMemcacheContent) {
requestResponseCounter.decrementAndGet();
}
}
}
}
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
super.channelInactive(ctx);
if (failOnMissingResponse) {
long missingResponses = requestResponseCounter.get();
if (missingResponses > 0) {
ctx.fireExceptionCaught(new PrematureChannelClosureException(
"channel gone inactive with " + missingResponses +
" missing response(s)"));
}
}
}
}
}