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.core.layout;
018
019 import java.nio.charset.Charset;
020 import java.text.SimpleDateFormat;
021 import java.util.Date;
022 import java.util.HashMap;
023 import java.util.Locale;
024 import java.util.Map;
025 import java.util.regex.Matcher;
026 import java.util.regex.Pattern;
027
028 import org.apache.logging.log4j.core.Layout;
029 import org.apache.logging.log4j.core.LogEvent;
030 import org.apache.logging.log4j.core.config.Node;
031 import org.apache.logging.log4j.core.config.plugins.Plugin;
032 import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
033 import org.apache.logging.log4j.core.config.plugins.PluginFactory;
034 import org.apache.logging.log4j.core.net.Facility;
035 import org.apache.logging.log4j.core.net.Priority;
036 import org.apache.logging.log4j.core.util.NetUtils;
037 import org.apache.logging.log4j.util.Chars;
038
039
040 /**
041 * Formats a log event as a BSD Log record.
042 */
043 @Plugin(name = "SyslogLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
044 public final class SyslogLayout extends AbstractStringLayout {
045
046 private static final long serialVersionUID = 1L;
047
048 /**
049 * Match newlines in a platform-independent manner.
050 */
051 public static final Pattern NEWLINE_PATTERN = Pattern.compile("\\r?\\n");
052
053 private final Facility facility;
054 private final boolean includeNewLine;
055 private final String escapeNewLine;
056
057 /**
058 * Date format used if header = true.
059 */
060 private final SimpleDateFormat dateFormat = new SimpleDateFormat("MMM dd HH:mm:ss", Locale.ENGLISH);
061 /**
062 * Host name used to identify messages from this appender.
063 */
064 private final String localHostname = NetUtils.getLocalHostname();
065
066 protected SyslogLayout(final Facility facility, final boolean includeNL, final String escapeNL, final Charset charset) {
067 super(charset);
068 this.facility = facility;
069 this.includeNewLine = includeNL;
070 this.escapeNewLine = escapeNL == null ? null : Matcher.quoteReplacement(escapeNL);
071 }
072
073 /**
074 * Formats a {@link org.apache.logging.log4j.core.LogEvent} in conformance with the BSD Log record format.
075 *
076 * @param event The LogEvent
077 * @return the event formatted as a String.
078 */
079 @Override
080 public String toSerializable(final LogEvent event) {
081 final StringBuilder buf = new StringBuilder();
082
083 buf.append('<');
084 buf.append(Priority.getPriority(facility, event.getLevel()));
085 buf.append('>');
086 addDate(event.getTimeMillis(), buf);
087 buf.append(Chars.SPACE);
088 buf.append(localHostname);
089 buf.append(Chars.SPACE);
090
091 String message = event.getMessage().getFormattedMessage();
092 if (null != escapeNewLine) {
093 message = NEWLINE_PATTERN.matcher(message).replaceAll(escapeNewLine);
094 }
095 buf.append(message);
096
097 if (includeNewLine) {
098 buf.append('\n');
099 }
100 return buf.toString();
101 }
102
103 private synchronized void addDate(final long timestamp, final StringBuilder buf) {
104 final int index = buf.length() + 4;
105 buf.append(dateFormat.format(new Date(timestamp)));
106 // RFC 3164 says leading space, not leading zero on days 1-9
107 if (buf.charAt(index) == '0') {
108 buf.setCharAt(index, Chars.SPACE);
109 }
110 }
111
112 /**
113 * Gets this SyslogLayout's content format. Specified by:
114 * <ul>
115 * <li>Key: "structured" Value: "false"</li>
116 * <li>Key: "dateFormat" Value: "MMM dd HH:mm:ss"</li>
117 * <li>Key: "format" Value: "<LEVEL>TIMESTAMP PROP(HOSTNAME) MESSAGE"</li>
118 * <li>Key: "formatType" Value: "logfilepatternreceiver" (format uses the keywords supported by
119 * LogFilePatternReceiver)</li>
120 * </ul>
121 *
122 * @return Map of content format keys supporting SyslogLayout
123 */
124 @Override
125 public Map<String, String> getContentFormat() {
126 final Map<String, String> result = new HashMap<String, String>();
127 result.put("structured", "false");
128 result.put("formatType", "logfilepatternreceiver");
129 result.put("dateFormat", dateFormat.toPattern());
130 result.put("format", "<LEVEL>TIMESTAMP PROP(HOSTNAME) MESSAGE");
131 return result;
132 }
133
134 /**
135 * Create a SyslogLayout.
136 * @param facility The Facility is used to try to classify the message.
137 * @param includeNewLine If true a newline will be appended to the result.
138 * @param escapeNL Pattern to use for replacing newlines.
139 * @param charset The character set.
140 * @return A SyslogLayout.
141 */
142 @PluginFactory
143 public static SyslogLayout createLayout(
144 @PluginAttribute(value = "facility", defaultString = "LOCAL0") final Facility facility,
145 @PluginAttribute(value = "newLine", defaultBoolean = false) final boolean includeNewLine,
146 @PluginAttribute("newLineEscape") final String escapeNL,
147 @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset) {
148 return new SyslogLayout(facility, includeNewLine, escapeNL, charset);
149 }
150 }