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.filter;
018
019 import java.lang.reflect.Field;
020 import java.util.Arrays;
021 import java.util.Comparator;
022 import java.util.regex.Matcher;
023 import java.util.regex.Pattern;
024
025 import org.apache.logging.log4j.Level;
026 import org.apache.logging.log4j.Marker;
027 import org.apache.logging.log4j.core.Filter;
028 import org.apache.logging.log4j.core.LogEvent;
029 import org.apache.logging.log4j.core.Logger;
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.PluginElement;
034 import org.apache.logging.log4j.core.config.plugins.PluginFactory;
035 import org.apache.logging.log4j.message.Message;
036
037 /**
038 * This filter returns the onMatch result if the message matches the regular expression.
039 *
040 * The "useRawMsg" attribute can be used to indicate whether the regular expression should be applied to the result of
041 * calling Message.getMessageFormat (true) or Message.getFormattedMessage() (false). The default is false.
042 *
043 */
044 @Plugin(name = "RegexFilter", category = Node.CATEGORY, elementType = Filter.ELEMENT_TYPE, printObject = true)
045 public final class RegexFilter extends AbstractFilter {
046
047 private static final long serialVersionUID = 1L;
048
049 private static final int DEFAULT_PATTERN_FLAGS = 0;
050 private final Pattern pattern;
051 private final boolean useRawMessage;
052
053 private RegexFilter(final boolean raw, final Pattern pattern, final Result onMatch, final Result onMismatch) {
054 super(onMatch, onMismatch);
055 this.pattern = pattern;
056 this.useRawMessage = raw;
057 }
058
059 @Override
060 public Result filter(final Logger logger, final Level level, final Marker marker, final String msg,
061 final Object... params) {
062 return filter(msg);
063 }
064
065 @Override
066 public Result filter(final Logger logger, final Level level, final Marker marker, final Object msg,
067 final Throwable t) {
068 if (msg == null) {
069 return onMismatch;
070 }
071 return filter(msg.toString());
072 }
073
074 @Override
075 public Result filter(final Logger logger, final Level level, final Marker marker, final Message msg,
076 final Throwable t) {
077 if (msg == null) {
078 return onMismatch;
079 }
080 final String text = useRawMessage ? msg.getFormat() : msg.getFormattedMessage();
081 return filter(text);
082 }
083
084 @Override
085 public Result filter(final LogEvent event) {
086 final String text = useRawMessage ? event.getMessage().getFormat() : event.getMessage().getFormattedMessage();
087 return filter(text);
088 }
089
090 private Result filter(final String msg) {
091 if (msg == null) {
092 return onMismatch;
093 }
094 final Matcher m = pattern.matcher(msg);
095 return m.matches() ? onMatch : onMismatch;
096 }
097
098 @Override
099 public String toString() {
100 final StringBuilder sb = new StringBuilder();
101 sb.append("useRaw=").append(useRawMessage);
102 sb.append(", pattern=").append(pattern.toString());
103 return sb.toString();
104 }
105
106 /**
107 * Create a Filter that matches a regular expression.
108 *
109 * @param regex
110 * The regular expression to match.
111 * @param patternFlags
112 * An array of Stirngs where each String is a {@link Pattern#compile(String, int)} compilation flag.
113 * @param useRawMsg
114 * If true, the raw message will be used, otherwise the formatted message will be used.
115 * @param match
116 * The action to perform when a match occurs.
117 * @param mismatch
118 * The action to perform when a mismatch occurs.
119 * @return The RegexFilter.
120 * @throws IllegalAccessException
121 * @throws IllegalArgumentException
122 */
123 @PluginFactory
124 public static RegexFilter createFilter(
125 //@formatter:off
126 @PluginAttribute("regex") final String regex,
127 @PluginElement("PatternFlags") final String[] patternFlags,
128 @PluginAttribute("useRawMsg") final Boolean useRawMsg,
129 @PluginAttribute("onMatch") final Result match,
130 @PluginAttribute("onMismatch") final Result mismatch)
131 //@formatter:on
132 throws IllegalArgumentException, IllegalAccessException {
133 if (regex == null) {
134 LOGGER.error("A regular expression must be provided for RegexFilter");
135 return null;
136 }
137 return new RegexFilter(useRawMsg, Pattern.compile(regex, toPatternFlags(patternFlags)), match, mismatch);
138 }
139
140 private static int toPatternFlags(final String[] patternFlags) throws IllegalArgumentException,
141 IllegalAccessException {
142 if (patternFlags == null || patternFlags.length == 0) {
143 return DEFAULT_PATTERN_FLAGS;
144 }
145 final Field[] fields = Pattern.class.getDeclaredFields();
146 final Comparator<Field> comparator = new Comparator<Field>() {
147
148 @Override
149 public int compare(final Field f1, final Field f2) {
150 return f1.getName().compareTo(f2.getName());
151 }
152 };
153 Arrays.sort(fields, comparator);
154 final String[] fieldNames = new String[fields.length];
155 for (int i = 0; i < fields.length; i++) {
156 fieldNames[i] = fields[i].getName();
157 }
158 int flags = DEFAULT_PATTERN_FLAGS;
159 for (final String test : patternFlags) {
160 final int index = Arrays.binarySearch(fieldNames, test);
161 if (index >= 0) {
162 final Field field = fields[index];
163 flags |= field.getInt(Pattern.class);
164 }
165 }
166 return flags;
167 }
168 }