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.core.layout;
018
019import java.io.IOException;
020import java.nio.charset.Charset;
021
022import org.apache.commons.csv.CSVFormat;
023import org.apache.commons.csv.CSVPrinter;
024import org.apache.commons.csv.QuoteMode;
025import org.apache.logging.log4j.core.Layout;
026import org.apache.logging.log4j.core.LogEvent;
027import org.apache.logging.log4j.core.config.Node;
028import org.apache.logging.log4j.core.config.plugins.Plugin;
029import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
030import org.apache.logging.log4j.core.config.plugins.PluginFactory;
031import org.apache.logging.log4j.message.Message;
032import org.apache.logging.log4j.status.StatusLogger;
033
034/**
035 * A Comma-Separated Value (CSV) layout to log event parameters.
036 * The event message is currently ignored. 
037 * 
038 * <p>
039 * Best used with:
040 * </p>
041 * <p>
042 * {@code logger.debug(new ObjectArrayMessage(1, 2, "Bob"));}
043 * </p>
044 * 
045 * Depends on Apache Commons CSV 1.2.
046 * 
047 * @since 2.4
048 */
049@Plugin(name = "CsvParameterLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
050public class CsvParameterLayout extends AbstractCsvLayout {
051
052    private static final long serialVersionUID = 1L;
053
054    public static AbstractCsvLayout createDefaultLayout() {
055        return new CsvParameterLayout(Charset.forName(DEFAULT_CHARSET), CSVFormat.valueOf(DEFAULT_FORMAT), null, null);
056    }
057
058    public static AbstractCsvLayout createLayout(final CSVFormat format) {
059        return new CsvParameterLayout(Charset.forName(DEFAULT_CHARSET), format, null, null);
060    }
061
062    @PluginFactory
063    public static AbstractCsvLayout createLayout(
064            // @formatter:off
065            @PluginAttribute(value = "format", defaultString = DEFAULT_FORMAT) final String format,
066            @PluginAttribute("delimiter") final Character delimiter,
067            @PluginAttribute("escape") final Character escape,
068            @PluginAttribute("quote") final Character quote,
069            @PluginAttribute("quoteMode") final QuoteMode quoteMode,
070            @PluginAttribute("nullString") final String nullString,
071            @PluginAttribute("recordSeparator") final String recordSeparator,
072            @PluginAttribute(value = "charset", defaultString = DEFAULT_CHARSET) final Charset charset,
073            @PluginAttribute("header") final String header,
074            @PluginAttribute("footer") final String footer)
075            // @formatter:on
076    {
077
078        final CSVFormat csvFormat = createFormat(format, delimiter, escape, quote, quoteMode, nullString, recordSeparator);
079        return new CsvParameterLayout(charset, csvFormat, header, footer);
080    }
081
082    public CsvParameterLayout(final Charset charset, final CSVFormat csvFormat, final String header, final String footer) {
083        super(charset, csvFormat, header, footer);
084    }
085
086    @Override
087    public String toSerializable(final LogEvent event) {
088        final Message message = event.getMessage();
089        final Object[] parameters = message.getParameters();
090        final StringBuilder buffer = new StringBuilder(1024);
091        try {
092            // Revisit when 1.3 is out so that we do not need to create a new
093            // printer for each event.
094            // No need to close the printer.
095            final CSVPrinter printer = new CSVPrinter(buffer, getFormat());
096            printer.printRecord(parameters);
097            return buffer.toString();
098        } catch (final IOException e) {
099            StatusLogger.getLogger().error(message, e);
100            return getFormat().getCommentMarker() + " " + e;
101        }
102    }
103
104}