001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.flume.appender;
018
019import java.io.Serializable;
020import java.util.Locale;
021
022import org.apache.logging.log4j.core.Filter;
023import org.apache.logging.log4j.core.Layout;
024import org.apache.logging.log4j.core.LogEvent;
025import org.apache.logging.log4j.core.appender.AbstractAppender;
026import org.apache.logging.log4j.core.config.Property;
027import org.apache.logging.log4j.core.config.plugins.Plugin;
028import org.apache.logging.log4j.core.config.plugins.PluginAliases;
029import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
030import org.apache.logging.log4j.core.config.plugins.PluginElement;
031import org.apache.logging.log4j.core.config.plugins.PluginFactory;
032import org.apache.logging.log4j.core.layout.Rfc5424Layout;
033import org.apache.logging.log4j.core.net.Facility;
034import org.apache.logging.log4j.core.util.Booleans;
035import org.apache.logging.log4j.core.util.Integers;
036
037/**
038 * An Appender that uses the Avro protocol to route events to Flume.
039 */
040@Plugin(name = "Flume", category = "Core", elementType = "appender", printObject = true)
041public final class FlumeAppender extends AbstractAppender implements FlumeEventFactory {
042
043    private static final long serialVersionUID = 1L;
044    private static final String[] EXCLUDED_PACKAGES = {"org.apache.flume", "org.apache.avro"};
045    private static final int DEFAULT_MAX_DELAY = 60000;
046
047    private static final int DEFAULT_LOCK_TIMEOUT_RETRY_COUNT = 5;
048
049    private final AbstractFlumeManager manager;
050
051    private final String mdcIncludes;
052    private final String mdcExcludes;
053    private final String mdcRequired;
054
055    private final String eventPrefix;
056
057    private final String mdcPrefix;
058
059    private final boolean compressBody;
060
061    private final FlumeEventFactory factory;
062
063    /**
064     * Which Manager will be used by the appender instance.
065     */
066    private enum ManagerType {
067        AVRO, EMBEDDED, PERSISTENT;
068
069        public static ManagerType getType(final String type) {
070            return valueOf(type.toUpperCase(Locale.US));
071        }
072    }
073
074    private FlumeAppender(final String name, final Filter filter, final Layout<? extends Serializable> layout,
075                          final boolean ignoreExceptions, final String includes, final String excludes,
076                          final String required, final String mdcPrefix, final String eventPrefix,
077                          final boolean compress, final FlumeEventFactory factory, final AbstractFlumeManager manager) {
078        super(name, filter, layout, ignoreExceptions);
079        this.manager = manager;
080        this.mdcIncludes = includes;
081        this.mdcExcludes = excludes;
082        this.mdcRequired = required;
083        this.eventPrefix = eventPrefix;
084        this.mdcPrefix = mdcPrefix;
085        this.compressBody = compress;
086        this.factory = factory == null ? this : factory;
087    }
088
089    /**
090     * Publish the event.
091     * @param event The LogEvent.
092     */
093    @Override
094    public void append(final LogEvent event) {
095        final String name = event.getLoggerName();
096        if (name != null) {
097            for (final String pkg : EXCLUDED_PACKAGES) {
098                if (name.startsWith(pkg)) {
099                    return;
100                }
101            }
102        }
103        final FlumeEvent flumeEvent = factory.createEvent(event, mdcIncludes, mdcExcludes, mdcRequired, mdcPrefix,
104            eventPrefix, compressBody);
105        flumeEvent.setBody(getLayout().toByteArray(flumeEvent));
106        manager.send(flumeEvent);
107    }
108
109    @Override
110    public void stop() {
111        super.stop();
112        manager.release();
113    }
114
115    /**
116     * Create a Flume event.
117     * @param event The Log4j LogEvent.
118     * @param includes comma separated list of mdc elements to include.
119     * @param excludes comma separated list of mdc elements to exclude.
120     * @param required comma separated list of mdc elements that must be present with a value.
121     * @param mdcPrefix The prefix to add to MDC key names.
122     * @param eventPrefix The prefix to add to event fields.
123     * @param compress If true the body will be compressed.
124     * @return A Flume Event.
125     */
126    @Override
127    public FlumeEvent createEvent(final LogEvent event, final String includes, final String excludes,
128                                  final String required, final String mdcPrefix, final String eventPrefix,
129                                  final boolean compress) {
130        return new FlumeEvent(event, mdcIncludes, mdcExcludes, mdcRequired, mdcPrefix,
131            eventPrefix, compressBody);
132    }
133
134    /**
135     * Create a Flume Avro Appender.
136     * @param agents An array of Agents.
137     * @param properties Properties to pass to the embedded agent.
138     * @param embedded true if the embedded agent manager should be used. otherwise the Avro manager will be used.
139     * <b>Note: </b><i>The embedded attribute is deprecated in favor of specifying the type attribute.</i>
140     * @param type Avro (default), Embedded, or Persistent.
141     * @param dataDir The directory where the Flume FileChannel should write its data.
142     * @param connectionTimeoutMillis The amount of time in milliseconds to wait before a connection times out. Minimum is
143     *                          1000.
144     * @param requestTimeoutMillis The amount of time in milliseconds to wait before a request times out. Minimum is 1000.
145     * @param agentRetries The number of times to retry an agent before failing to the next agent.
146     * @param maxDelayMillis The maximum number of milliseconds to wait for a complete batch.
147     * @param name The name of the Appender.
148     * @param ignore If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise
149     *               they are propagated to the caller.
150     * @param excludes A comma separated list of MDC elements to exclude.
151     * @param includes A comma separated list of MDC elements to include.
152     * @param required A comma separated list of MDC elements that are required.
153     * @param mdcPrefix The prefix to add to MDC key names.
154     * @param eventPrefix The prefix to add to event key names.
155     * @param compressBody If true the event body will be compressed.
156     * @param batchSize Number of events to include in a batch. Defaults to 1.
157     * @param lockTimeoutRetries Times to retry a lock timeout when writing to Berkeley DB.
158     * @param factory The factory to use to create Flume events.
159     * @param layout The layout to format the event.
160     * @param filter A Filter to filter events.
161     *
162     * @return A Flume Avro Appender.
163     */
164    @PluginFactory
165    public static FlumeAppender createAppender(@PluginElement("Agents") Agent[] agents,
166                                               @PluginElement("Properties") final Property[] properties,
167                                               @PluginAttribute("embedded") final String embedded,
168                                               @PluginAttribute("type") final String type,
169                                               @PluginAttribute("dataDir") final String dataDir,
170                                               @PluginAliases("connectTimeout")
171                                               @PluginAttribute("connectTimeoutMillis") final String connectionTimeoutMillis,
172                                               @PluginAliases("requestTimeout")
173                                               @PluginAttribute("requestTimeoutMillis") final String requestTimeoutMillis,
174                                               @PluginAttribute("agentRetries") final String agentRetries,
175                                               @PluginAliases("maxDelay") // deprecated
176                                               @PluginAttribute("maxDelayMillis") final String maxDelayMillis,
177                                               @PluginAttribute("name") final String name,
178                                               @PluginAttribute("ignoreExceptions") final String ignore,
179                                               @PluginAttribute("mdcExcludes") final String excludes,
180                                               @PluginAttribute("mdcIncludes") final String includes,
181                                               @PluginAttribute("mdcRequired") final String required,
182                                               @PluginAttribute("mdcPrefix") final String mdcPrefix,
183                                               @PluginAttribute("eventPrefix") final String eventPrefix,
184                                               @PluginAttribute("compress") final String compressBody,
185                                               @PluginAttribute("batchSize") final String batchSize,
186                                               @PluginAttribute("lockTimeoutRetries") final String lockTimeoutRetries,
187                                               @PluginElement("FlumeEventFactory") final FlumeEventFactory factory,
188                                               @PluginElement("Layout") Layout<? extends Serializable> layout,
189                                               @PluginElement("Filter") final Filter filter) {
190
191        final boolean embed = embedded != null ? Boolean.parseBoolean(embedded) :
192            (agents == null || agents.length == 0) && properties != null && properties.length > 0;
193        final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);
194        final boolean compress = Booleans.parseBoolean(compressBody, true);
195        ManagerType managerType;
196        if (type != null) {
197            if (embed && embedded != null) {
198                try {
199                    managerType = ManagerType.getType(type);
200                    LOGGER.warn("Embedded and type attributes are mutually exclusive. Using type " + type);
201                } catch (final Exception ex) {
202                    LOGGER.warn("Embedded and type attributes are mutually exclusive and type " + type +
203                        " is invalid.");
204                    managerType = ManagerType.EMBEDDED;
205                }
206            } else {
207                try {
208                    managerType = ManagerType.getType(type);
209                } catch (final Exception ex) {
210                    LOGGER.warn("Type " + type + " is invalid.");
211                    managerType = ManagerType.EMBEDDED;
212                }
213            }
214        }  else if (embed) {
215           managerType = ManagerType.EMBEDDED;
216        }  else {
217           managerType = ManagerType.AVRO;
218        }
219
220        final int batchCount = Integers.parseInt(batchSize, 1);
221        final int connectTimeoutMillis = Integers.parseInt(connectionTimeoutMillis, 0);
222        final int reqTimeoutMillis = Integers.parseInt(requestTimeoutMillis, 0);
223        final int retries = Integers.parseInt(agentRetries, 0);
224        final int lockTimeoutRetryCount = Integers.parseInt(lockTimeoutRetries, DEFAULT_LOCK_TIMEOUT_RETRY_COUNT);
225        final int delayMillis = Integers.parseInt(maxDelayMillis, DEFAULT_MAX_DELAY);
226
227        if (layout == null) {
228            final int enterpriseNumber = Rfc5424Layout.DEFAULT_ENTERPRISE_NUMBER;
229            layout = Rfc5424Layout.createLayout(Facility.LOCAL0, null, enterpriseNumber, true, Rfc5424Layout.DEFAULT_MDCID,
230                    mdcPrefix, eventPrefix, false, null, null, null, excludes, includes, required, null, false, null,
231                    null);
232        }
233
234        if (name == null) {
235            LOGGER.error("No name provided for Appender");
236            return null;
237        }
238
239        AbstractFlumeManager manager;
240
241        switch (managerType) {
242            case EMBEDDED:
243                manager = FlumeEmbeddedManager.getManager(name, agents, properties, batchCount, dataDir);
244                break;
245            case AVRO:
246                if (agents == null || agents.length == 0) {
247                    LOGGER.debug("No agents provided, using defaults");
248                    agents = new Agent[] {Agent.createAgent(null, null)};
249                }
250                manager = FlumeAvroManager.getManager(name, agents, batchCount, delayMillis, retries, connectTimeoutMillis, reqTimeoutMillis);
251                break;
252            case PERSISTENT:
253                if (agents == null || agents.length == 0) {
254                    LOGGER.debug("No agents provided, using defaults");
255                    agents = new Agent[] {Agent.createAgent(null, null)};
256                }
257                manager = FlumePersistentManager.getManager(name, agents, properties, batchCount, retries,
258                    connectTimeoutMillis, reqTimeoutMillis, delayMillis, lockTimeoutRetryCount, dataDir);
259                break;
260            default:
261                LOGGER.debug("No manager type specified. Defaulting to AVRO");
262                if (agents == null || agents.length == 0) {
263                    LOGGER.debug("No agents provided, using defaults");
264                    agents = new Agent[] {Agent.createAgent(null, null)};
265                }
266                manager = FlumeAvroManager.getManager(name, agents, batchCount, delayMillis, retries, connectTimeoutMillis, reqTimeoutMillis);
267        }
268
269        if (manager == null) {
270            return null;
271        }
272
273        return new FlumeAppender(name, filter, layout,  ignoreExceptions, includes,
274            excludes, required, mdcPrefix, eventPrefix, compress, factory, manager);
275    }
276}