GelfUdpTransport.java

/*
 * Copyright 2014 TORCH GmbH
 *
 * 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 org.graylog2.gelfclient.transport;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.socket.DatagramPacket;
import io.netty.channel.socket.nio.NioDatagramChannel;
import org.graylog2.gelfclient.GelfConfiguration;
import org.graylog2.gelfclient.encoder.GelfCompressionEncoder;
import org.graylog2.gelfclient.encoder.GelfMessageChunkEncoder;
import org.graylog2.gelfclient.encoder.GelfMessageJsonEncoder;
import org.graylog2.gelfclient.encoder.GelfMessageUdpEncoder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * A {@link GelfTransport} implementation that uses UDP to send GELF messages.
 * <p>This class is thread-safe.</p>
 */
public class GelfUdpTransport extends AbstractGelfTransport {
    private static final Logger LOG = LoggerFactory.getLogger(GelfUdpTransport.class);

    /**
     * Creates a new UDP GELF transport.
     *
     * @param config the GELF client configuration
     */
    public GelfUdpTransport(final GelfConfiguration config) {
        super(config);
    }

    @Override
    protected void createBootstrap(final EventLoopGroup workerGroup) {
        final Bootstrap bootstrap = new Bootstrap();
        final GelfSenderThread senderThread = new GelfSenderThread(queue, config.getMaxInflightSends());

        bootstrap.group(workerGroup)
                .channel(NioDatagramChannel.class)
                .handler(new ChannelInitializer<Channel>() {
                    @Override
                    protected void initChannel(Channel ch) throws Exception {
                        ch.pipeline().addLast(new GelfMessageUdpEncoder(config.getRemoteAddress()));
                        ch.pipeline().addLast(new GelfMessageChunkEncoder());
                        ch.pipeline().addLast(new GelfCompressionEncoder());
                        ch.pipeline().addLast(new GelfMessageJsonEncoder());
                        ch.pipeline().addLast(new SimpleChannelInboundHandler<DatagramPacket>() {
                            @Override
                            protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket msg) throws Exception {
                                // We do not receive data.
                            }

                            @Override
                            public void channelActive(ChannelHandlerContext ctx) throws Exception {
                                senderThread.start(ctx.channel());
                            }

                            @Override
                            public void channelInactive(ChannelHandlerContext ctx) throws Exception {
                                senderThread.stop();
                            }

                            @Override
                            public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
                                LOG.error("Exception caught", cause);
                            }
                        });
                    }
                });

        if (config.getSendBufferSize() != -1) {
            bootstrap.option(ChannelOption.SO_SNDBUF, config.getSendBufferSize());
        }

        bootstrap.bind(0);
    }
}