/* * Logback GELF - zero dependencies Logback GELF appender library. * Copyright (C) 2016 Oliver Siegmar * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ package de.siegmar.logbackgelf; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStream; import java.net.InetSocketAddress; import java.net.SocketAddress; import java.nio.ByteBuffer; import java.nio.channels.DatagramChannel; import java.util.zip.DeflaterOutputStream; public class GelfUdpAppender extends AbstractGelfAppender { /** * Maximum size of GELF chunks in bytes. Default chunk size is 508 - this prevents * IP packet fragmentation. This is also the recommended minimum. */ private Integer maxChunkSize; /** * If true, compression of GELF messages is enabled. Default: true. */ private boolean useCompression = true; private MessageIdSupplier messageIdSupplier = new MessageIdSupplier(); private RobustChannel robustChannel; private GelfUdpChunker chunker; private AddressResolver addressResolver; public Integer getMaxChunkSize() { return maxChunkSize; } public void setMaxChunkSize(final Integer maxChunkSize) { this.maxChunkSize = maxChunkSize; } public boolean isUseCompression() { return useCompression; } public void setUseCompression(final boolean useCompression) { this.useCompression = useCompression; } public MessageIdSupplier getMessageIdSupplier() { return messageIdSupplier; } public void setMessageIdSupplier(final MessageIdSupplier messageIdSupplier) { this.messageIdSupplier = messageIdSupplier; } @Override protected void startAppender() throws IOException { robustChannel = new RobustChannel(); chunker = new GelfUdpChunker(messageIdSupplier, maxChunkSize); addressResolver = new AddressResolver(getGraylogHost()); } @Override protected void appendMessage(final byte[] binMessage) throws IOException { final byte[] messageToSend = useCompression ? compress(binMessage) : binMessage; final InetSocketAddress remote = new InetSocketAddress(addressResolver.resolve(), getGraylogPort()); for (final ByteBuffer chunk : chunker.chunks(messageToSend)) { while (chunk.hasRemaining()) { robustChannel.send(chunk, remote); } } } private static byte[] compress(final byte[] binMessage) { final ByteArrayOutputStream bos = new ByteArrayOutputStream(binMessage.length); try (OutputStream deflaterOut = new DeflaterOutputStream(bos)) { deflaterOut.write(binMessage); } catch (IOException e) { throw new IllegalStateException(e); } return bos.toByteArray(); } @Override protected void close() throws IOException { robustChannel.close(); } private static final class RobustChannel { private volatile DatagramChannel channel; private volatile boolean stopped; RobustChannel() throws IOException { this.channel = DatagramChannel.open(); } void send(final ByteBuffer src, final SocketAddress target) throws IOException { getChannel().send(src, target); } private DatagramChannel getChannel() throws IOException { DatagramChannel tmp = channel; if (!tmp.isOpen()) { synchronized (this) { tmp = channel; if (!tmp.isOpen() && !stopped) { tmp = DatagramChannel.open(); channel = tmp; } } } return tmp; } synchronized void close() throws IOException { channel.close(); stopped = true; } } }