/*
* Licensed to ElasticSearch and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. ElasticSearch 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.elasticsearch.memcached.netty;
import org.elasticsearch.common.Bytes;
import org.elasticsearch.common.Unicode;
import org.elasticsearch.common.bytes.ChannelBufferBytesReference;
import org.elasticsearch.common.io.stream.CachedStreamOutput;
import org.elasticsearch.common.io.stream.NettyCachedStreamOutput;
import org.elasticsearch.common.netty.buffer.ChannelBuffer;
import org.elasticsearch.common.netty.buffer.ChannelBuffers;
import org.elasticsearch.common.netty.channel.Channel;
import org.elasticsearch.common.netty.channel.ChannelFuture;
import org.elasticsearch.common.netty.channel.ChannelFutureListener;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.memcached.MemcachedRestRequest;
import org.elasticsearch.memcached.MemcachedTransportException;
import org.elasticsearch.rest.RestChannel;
import org.elasticsearch.rest.RestRequest;
import org.elasticsearch.rest.RestResponse;
import org.elasticsearch.rest.XContentRestResponse;
import org.elasticsearch.transport.netty.NettyTransport;
import org.elasticsearch.transport.netty.ServerNettyTransport;
import java.nio.charset.Charset;
/**
*/
public class MemcachedRestChannel implements RestChannel {
public static final ChannelBuffer CRLF = ChannelBuffers.copiedBuffer("\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer VALUE = ChannelBuffers.copiedBuffer("VALUE ", Charset.forName("US-ASCII"));
private static final ChannelBuffer EXISTS = ChannelBuffers.copiedBuffer("EXISTS\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer NOT_FOUND = ChannelBuffers.copiedBuffer("NOT_FOUND\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer NOT_STORED = ChannelBuffers.copiedBuffer("NOT_STORED\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer STORED = ChannelBuffers.copiedBuffer("STORED\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer DELETED = ChannelBuffers.copiedBuffer("DELETED\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer END = ChannelBuffers.copiedBuffer("END\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer OK = ChannelBuffers.copiedBuffer("OK\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer ERROR = ChannelBuffers.copiedBuffer("ERROR\r\n", Charset.forName("US-ASCII"));
private static final ChannelBuffer CLIENT_ERROR = ChannelBuffers.copiedBuffer("CLIENT_ERROR\r\n", Charset.forName("US-ASCII"));
private final Channel channel;
private final MemcachedRestRequest request;
public MemcachedRestChannel(Channel channel, MemcachedRestRequest request) {
this.channel = channel;
this.request = request;
}
@Override
public void sendResponse(RestResponse response) {
if (request.isBinary()) {
if (request.isQuiet() && response.status().getStatus() < 500) {
// nothing to send and all is well
return;
}
try {
ChannelBuffer writeBuffer = ChannelBuffers.dynamicBuffer(24 + request.getUriBytes().length + response.contentLength() + 12);
writeBuffer.writeByte(0x81); // magic
if (request.method() == RestRequest.Method.GET) {
writeBuffer.writeByte(0x00); // opcode
} else if (request.method() == RestRequest.Method.POST) {
if (request.isQuiet()) {
writeBuffer.writeByte(0x11); // opcode
} else {
writeBuffer.writeByte(0x01); // opcode
}
} else if (request.method() == RestRequest.Method.DELETE) {
writeBuffer.writeByte(0x04); // opcode
}
short keyLength = request.method() == RestRequest.Method.GET ? (short) request.getUriBytes().length : 0;
writeBuffer.writeShort(keyLength);
int extrasLength = request.method() == RestRequest.Method.GET ? 4 : 0;
writeBuffer.writeByte(extrasLength); // extra length = flags + expiry
writeBuffer.writeByte(0); // data type unused
if (response.status().getStatus() >= 500) {
// TODO should we use this?
writeBuffer.writeShort(0x0A); // status code
} else {
writeBuffer.writeShort(0x0000); // OK
}
int dataLength = request.method() == RestRequest.Method.GET ? response.contentLength() : 0;
writeBuffer.writeInt(dataLength + keyLength + extrasLength); // data length
writeBuffer.writeInt(request.getOpaque()); // opaque
writeBuffer.writeLong(0); // cas
if (extrasLength > 0) {
writeBuffer.writeShort(0);
writeBuffer.writeShort(0);
}
if (keyLength > 0) {
writeBuffer.writeBytes(request.getUriBytes());
}
ChannelFutureListener releaseContentListener = null;
if (dataLength > 0) {
if (response instanceof XContentRestResponse) {
// if its a builder based response, and it was created with a CachedStreamOutput, we can release it
// after we write the response, and no need to do an extra copy because its not thread safe
XContentBuilder builder = ((XContentRestResponse) response).builder();
if (builder.payload() instanceof NettyCachedStreamOutput.Entry) {
releaseContentListener = new ServerNettyTransport.CacheFutureListener((NettyCachedStreamOutput.Entry) builder.payload());
ChannelBuffer buf = ((ChannelBufferBytesReference)builder.bytes()).toChannelBuffer();
writeBuffer = ChannelBuffers.wrappedBuffer(writeBuffer, buf);
} else if (response.contentThreadSafe()) {
ChannelBuffer buf = ((ChannelBufferBytesReference)builder.bytes()).toChannelBuffer();
writeBuffer = ChannelBuffers.wrappedBuffer(writeBuffer, buf);
} else {
writeBuffer.writeBytes(response.content(), 0, response.contentLength());
}
} else {
if (response.contentThreadSafe()) {
ChannelBuffer buf = ChannelBuffers.wrappedBuffer(response.content(), 0, response.contentLength());
writeBuffer = ChannelBuffers.wrappedBuffer(writeBuffer, buf);
} else {
writeBuffer.writeBytes(response.content(), 0, response.contentLength());
}
}
}
ChannelFuture future = channel.write(writeBuffer);
if (releaseContentListener != null) {
future.addListener(releaseContentListener);
}
} catch (Exception e) {
throw new MemcachedTransportException("Failed to write response", e);
}
} else {
if (response.status().getStatus() >= 500) {
channel.write(ERROR.duplicate());
} else {
if (request.method() == RestRequest.Method.POST) {
// TODO this is SET, can we send a payload?
channel.write(STORED.duplicate());
} else if (request.method() == RestRequest.Method.DELETE) {
channel.write(DELETED.duplicate());
} else { // GET
try {
ChannelBuffer writeBuffer = ChannelBuffers.dynamicBuffer(response.contentLength() + 512);
writeBuffer.writeBytes(VALUE.duplicate());
writeBuffer.writeBytes(Unicode.fromStringAsBytes(request.uri()));
writeBuffer.writeByte(' ');
writeBuffer.writeByte('0');
writeBuffer.writeByte(' ');
writeBuffer.writeBytes(Bytes.itoa(response.contentLength()));
writeBuffer.writeByte('\r');
writeBuffer.writeByte('\n');
writeBuffer.writeBytes(response.content(), 0, response.contentLength());
writeBuffer.writeByte('\r');
writeBuffer.writeByte('\n');
writeBuffer.writeBytes(END.duplicate());
channel.write(writeBuffer);
} catch (Exception e) {
throw new MemcachedTransportException("Failed to write 'get' response", e);
}
}
}
}
}
}