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     */
017    package org.apache.logging.log4j.nosql.appender;
018    
019    import org.apache.logging.log4j.core.Filter;
020    import org.apache.logging.log4j.core.appender.AbstractAppender;
021    import org.apache.logging.log4j.core.appender.db.AbstractDatabaseAppender;
022    import org.apache.logging.log4j.core.config.plugins.Plugin;
023    import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
024    import org.apache.logging.log4j.core.config.plugins.PluginElement;
025    import org.apache.logging.log4j.core.config.plugins.PluginFactory;
026    import org.apache.logging.log4j.core.util.Booleans;
027    
028    /**
029     * This Appender writes logging events to a NoSQL database using a configured NoSQL provider. It requires
030     * implementations of {@link NoSqlObject}, {@link NoSqlConnection}, and {@link NoSqlProvider} to "know" how to write
031     * events to the chosen NoSQL database. Two provider implementations are provided: MongoDB
032     * (org.mongodb:mongo-java-driver:2.11.1 or newer must be on the classpath) and Apache CouchDB
033     * (org.lightcouch:lightcouch:0.0.5 or newer must be on the classpath). For examples on how to write your own NoSQL
034     * provider, see the simple source code for the MongoDB and CouchDB providers.
035     *
036     * @see NoSqlObject
037     * @see NoSqlConnection
038     * @see NoSqlProvider
039     */
040    @Plugin(name = "NoSql", category = "Core", elementType = "appender", printObject = true)
041    public final class NoSqlAppender extends AbstractDatabaseAppender<NoSqlDatabaseManager<?>> {
042        private final String description;
043    
044        private NoSqlAppender(final String name, final Filter filter, final boolean ignoreExceptions,
045                              final NoSqlDatabaseManager<?> manager) {
046            super(name, filter, ignoreExceptions, manager);
047            this.description = this.getName() + "{ manager=" + this.getManager() + " }";
048        }
049    
050        @Override
051        public String toString() {
052            return this.description;
053        }
054    
055        /**
056         * Factory method for creating a NoSQL appender within the plugin manager.
057         *
058         * @param name The name of the appender.
059         * @param ignore If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise
060         *               they are propagated to the caller.
061         * @param filter The filter, if any, to use.
062         * @param bufferSize If an integer greater than 0, this causes the appender to buffer log events and flush whenever
063         *                   the buffer reaches this size.
064         * @param provider The NoSQL provider that provides connections to the chosen NoSQL database.
065         * @return a new NoSQL appender.
066         */
067        @PluginFactory
068        public static NoSqlAppender createAppender(
069                @PluginAttribute("name") final String name,
070                @PluginAttribute("ignoreExceptions") final String ignore,
071                @PluginElement("Filter") final Filter filter,
072                @PluginAttribute("bufferSize") final String bufferSize,
073                @PluginElement("NoSqlProvider") final NoSqlProvider<?> provider) {
074            if (provider == null) {
075                LOGGER.error("NoSQL provider not specified for appender [{}].", name);
076                return null;
077            }
078    
079            final int bufferSizeInt = AbstractAppender.parseInt(bufferSize, 0);
080            final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);
081    
082            final String managerName = "noSqlManager{ description=" + name + ", bufferSize=" + bufferSizeInt
083                    + ", provider=" + provider + " }";
084    
085            final NoSqlDatabaseManager<?> manager = NoSqlDatabaseManager.getNoSqlDatabaseManager(
086                    managerName, bufferSizeInt, provider
087            );
088            if (manager == null) {
089                return null;
090            }
091    
092            return new NoSqlAppender(name, filter, ignoreExceptions, manager);
093        }
094    }