    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 static final long serialVersionUID = 1L;
    043        private final String description;
    044
    045        private NoSqlAppender(final String name, final Filter filter, final boolean ignoreExceptions,
    046                              final NoSqlDatabaseManager<?> manager) {
    047            super(name, filter, ignoreExceptions, manager);
    048            this.description = this.getName() + "{ manager=" + this.getManager() + " }";
    049        }
    050
    051        @Override
    052        public String toString() {
    053            return this.description;
    054        }
    055
    056        /**
    057         * Factory method for creating a NoSQL appender within the plugin manager.
    058         *
    059         * @param name The name of the appender.
    060         * @param ignore If {@code "true"} (default) exceptions encountered when appending events are logged; otherwise
    061         *               they are propagated to the caller.
    062         * @param filter The filter, if any, to use.
    063         * @param bufferSize If an integer greater than 0, this causes the appender to buffer log events and flush whenever
    064         *                   the buffer reaches this size.
    065         * @param provider The NoSQL provider that provides connections to the chosen NoSQL database.
    066         * @return a new NoSQL appender.
    067         */
    068        @PluginFactory
    069        public static NoSqlAppender createAppender(
    070                @PluginAttribute("name") final String name,
    071                @PluginAttribute("ignoreExceptions") final String ignore,
    072                @PluginElement("Filter") final Filter filter,
    073                @PluginAttribute("bufferSize") final String bufferSize,
    074                @PluginElement("NoSqlProvider") final NoSqlProvider<?> provider) {
    075            if (provider == null) {
    076                LOGGER.error("NoSQL provider not specified for appender [{}].", name);
    077                return null;
    078            }
    079
    080            final int bufferSizeInt = AbstractAppender.parseInt(bufferSize, 0);
    081            final boolean ignoreExceptions = Booleans.parseBoolean(ignore, true);
    082
    083            final String managerName = "noSqlManager{ description=" + name + ", bufferSize=" + bufferSizeInt
    084                    + ", provider=" + provider + " }";
    085
    086            final NoSqlDatabaseManager<?> manager = NoSqlDatabaseManager.getNoSqlDatabaseManager(
    087                    managerName, bufferSizeInt, provider
    088            );
    089            if (manager == null) {
    090                return null;
    091            }
    092
    093            return new NoSqlAppender(name, filter, ignoreExceptions, manager);
    094        }
    095    }