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.nio.charset.Charset;
020import java.util.HashMap;
021import java.util.List;
022import java.util.Map;
023
024import org.apache.logging.log4j.core.Layout;
025import org.apache.logging.log4j.core.LogEvent;
026import org.apache.logging.log4j.core.config.Configuration;
027import org.apache.logging.log4j.core.config.DefaultConfiguration;
028import org.apache.logging.log4j.core.config.Node;
029import org.apache.logging.log4j.core.config.plugins.Plugin;
030import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
031import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
032import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
033import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
034import org.apache.logging.log4j.core.config.plugins.PluginElement;
035import org.apache.logging.log4j.core.config.plugins.PluginFactory;
036import org.apache.logging.log4j.core.pattern.LogEventPatternConverter;
037import org.apache.logging.log4j.core.pattern.PatternFormatter;
038import org.apache.logging.log4j.core.pattern.PatternParser;
039import org.apache.logging.log4j.core.pattern.RegexReplacement;
040
041/**
042 * A flexible layout configurable with pattern string.
043 * <p>
044 * The goal of this class is to {@link org.apache.logging.log4j.core.Layout#toByteArray format} a {@link LogEvent} and
045 * return the results. The format of the result depends on the <em>conversion pattern</em>.
046 * </p>
047 * <p>
048 * The conversion pattern is closely related to the conversion pattern of the printf function in C. A conversion pattern
049 * is composed of literal text and format control expressions called <em>conversion specifiers</em>.
050 * </p>
051 * <p>
052 * See the Log4j Manual for details on the supported pattern converters.
053 * </p>
054 */
055@Plugin(name = "PatternLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
056public final class PatternLayout extends AbstractStringLayout {
057
058    private static final long serialVersionUID = 1L;
059
060    /**
061     * Default pattern string for log output. Currently set to the
062     * string <b>"%m%n"</b> which just prints the application supplied
063     * message.
064     */
065    public static final String DEFAULT_CONVERSION_PATTERN = "%m%n";
066
067    /**
068     * A conversion pattern equivalent to the TTCCCLayout.
069     * Current value is <b>%r [%t] %p %c %x - %m%n</b>.
070     */
071    public static final String TTCC_CONVERSION_PATTERN =
072        "%r [%t] %p %c %x - %m%n";
073
074    /**
075     * A simple pattern.
076     * Current value is <b>%d [%t] %p %c - %m%n</b>.
077     */
078    public static final String SIMPLE_CONVERSION_PATTERN =
079        "%d [%t] %p %c - %m%n";
080
081    /** Key to identify pattern converters. */
082    public static final String KEY = "Converter";
083
084    /**
085     * Initial converter for pattern.
086     */
087    private final PatternFormatter[] formatters;
088
089    private static ThreadLocal<StringBuilder> strBuilder = new ThreadLocal<StringBuilder>() {
090        @Override
091        protected StringBuilder initialValue() {
092            return new StringBuilder(1024);
093        }        
094    };
095
096    /**
097     * Conversion pattern.
098     */
099    private final String conversionPattern;
100
101
102    /**
103     * The current Configuration.
104     */
105    private final Configuration config;
106
107    private final RegexReplacement replace;
108
109    private final boolean alwaysWriteExceptions;
110
111    private final boolean noConsoleNoAnsi;
112
113    /**
114     * Constructs a EnhancedPatternLayout using the supplied conversion pattern.
115     *
116     * @param config The Configuration.
117     * @param replace The regular expression to match.
118     * @param pattern conversion pattern.
119     * @param charset The character set.
120     * @param alwaysWriteExceptions Whether or not exceptions should always be handled in this pattern (if {@code true},
121     *                         exceptions will be written even if the pattern does not specify so).
122     * @param noConsoleNoAnsi
123     *            If {@code "true"} (default) and {@link System#console()} is null, do not output ANSI escape codes
124     * @param header
125     */
126    private PatternLayout(final Configuration config, final RegexReplacement replace, final String pattern,
127                          final Charset charset, final boolean alwaysWriteExceptions, final boolean noConsoleNoAnsi,
128                          final String header, final String footer) {
129        super(charset, toBytes(header, charset), toBytes(footer, charset));
130        this.replace = replace;
131        this.conversionPattern = pattern;
132        this.config = config;
133        this.alwaysWriteExceptions = alwaysWriteExceptions;
134        this.noConsoleNoAnsi = noConsoleNoAnsi;
135        final PatternParser parser = createPatternParser(config);
136        try {
137            List<PatternFormatter> list = parser.parse(pattern == null ? DEFAULT_CONVERSION_PATTERN : pattern, 
138                    this.alwaysWriteExceptions, this.noConsoleNoAnsi);
139            this.formatters = list.toArray(new PatternFormatter[0]);
140        } catch (RuntimeException ex) {
141            throw new IllegalArgumentException("Cannot parse pattern '" + pattern + "'", ex);
142        }
143    }
144
145    private byte[] strSubstitutorReplace(final byte... b) {
146        if (b != null && config != null) {
147            return getBytes(config.getStrSubstitutor().replace(new String(b, getCharset())));
148        }
149        return b;
150    }
151
152    @Override
153    public byte[] getHeader() {
154        return strSubstitutorReplace(super.getHeader());
155    }
156
157    @Override
158    public byte[] getFooter() {
159        return strSubstitutorReplace(super.getFooter());
160    }
161
162    /**
163     * Gets the conversion pattern.
164     *
165     * @return the conversion pattern.
166     */
167    public String getConversionPattern() {
168        return conversionPattern;
169    }
170
171    /**
172     * Gets this PatternLayout's content format. Specified by:
173     * <ul>
174     * <li>Key: "structured" Value: "false"</li>
175     * <li>Key: "formatType" Value: "conversion" (format uses the keywords supported by OptionConverter)</li>
176     * <li>Key: "format" Value: provided "conversionPattern" param</li>
177     * </ul>
178     * 
179     * @return Map of content format keys supporting PatternLayout
180     */
181    @Override
182    public Map<String, String> getContentFormat()
183    {
184        final Map<String, String> result = new HashMap<>();
185        result.put("structured", "false");
186        result.put("formatType", "conversion");
187        result.put("format", conversionPattern);
188        return result;
189    }
190
191    /**
192     * Formats a logging event to a writer.
193     *
194     *
195     * @param event logging event to be formatted.
196     * @return The event formatted as a String.
197     */
198    @Override
199    public String toSerializable(final LogEvent event) {
200        final StringBuilder buf = strBuilder.get();
201        buf.setLength(0);
202        final int len = formatters.length;
203        for (int i = 0; i < len; i++) {
204            formatters[i].format(event, buf);
205        }
206        String str = buf.toString();
207        if (replace != null) {
208            str = replace.format(str);
209        }
210        return str;
211    }
212
213    /**
214     * Create a PatternParser.
215     * @param config The Configuration.
216     * @return The PatternParser.
217     */
218    public static PatternParser createPatternParser(final Configuration config) {
219        if (config == null) {
220            return new PatternParser(config, KEY, LogEventPatternConverter.class);
221        }
222        PatternParser parser = config.getComponent(KEY);
223        if (parser == null) {
224            parser = new PatternParser(config, KEY, LogEventPatternConverter.class);
225            config.addComponent(KEY, parser);
226            parser = (PatternParser) config.getComponent(KEY);
227        }
228        return parser;
229    }
230
231    @Override
232    public String toString() {
233        return conversionPattern;
234    }
235
236    /**
237     * Create a pattern layout.
238     *
239     * @param pattern
240     *        The pattern. If not specified, defaults to DEFAULT_CONVERSION_PATTERN.
241     * @param config
242     *        The Configuration. Some Converters require access to the Interpolator.
243     * @param replace
244     *        A Regex replacement String.
245     * @param charset
246     *        The character set.
247     * @param alwaysWriteExceptions
248     *        If {@code "true"} (default) exceptions are always written even if the pattern contains no exception tokens.
249     * @param noConsoleNoAnsi
250     *        If {@code "true"} (default is false) and {@link System#console()} is null, do not output ANSI escape codes
251     * @param header
252     *        The footer to place at the top of the document, once.
253     * @param footer
254     *        The footer to place at the bottom of the document, once.
255     * @return The PatternLayout.
256     */
257    @PluginFactory
258    public static PatternLayout createLayout(
259            @PluginAttribute(value = "pattern", defaultString = DEFAULT_CONVERSION_PATTERN) final String pattern,
260            @PluginConfiguration final Configuration config,
261            @PluginElement("Replace") final RegexReplacement replace,
262            @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
263            @PluginAttribute(value = "alwaysWriteExceptions", defaultBoolean = true) final boolean alwaysWriteExceptions,
264            @PluginAttribute(value = "noConsoleNoAnsi", defaultBoolean = false) final boolean noConsoleNoAnsi,
265            @PluginAttribute("header") final String header,
266            @PluginAttribute("footer") final String footer) {
267        return newBuilder()
268            .withPattern(pattern)
269            .withConfiguration(config)
270            .withRegexReplacement(replace)
271            .withCharset(charset)
272            .withAlwaysWriteExceptions(alwaysWriteExceptions)
273            .withNoConsoleNoAnsi(noConsoleNoAnsi)
274            .withHeader(header)
275            .withFooter(footer)
276            .build();
277    }
278
279    /**
280     * Creates a PatternLayout using the default options. These options include using UTF-8, the default conversion
281     * pattern, exceptions being written, and with ANSI escape codes.
282     *
283     * @return the PatternLayout.
284     * @see #DEFAULT_CONVERSION_PATTERN Default conversion pattern
285     */
286    public static PatternLayout createDefaultLayout() {
287        return newBuilder().build();
288    }
289
290    /**
291     * Creates a builder for a custom PatternLayout.
292     * @return a PatternLayout builder.
293     */
294    @PluginBuilderFactory
295    public static Builder newBuilder() {
296        return new Builder();
297    }
298
299    /**
300     * Custom PatternLayout builder. Use the {@link PatternLayout#newBuilder() builder factory method} to create this.
301     */
302    public static class Builder implements org.apache.logging.log4j.core.util.Builder<PatternLayout> {
303
304        // FIXME: it seems rather redundant to repeat default values (same goes for field names)
305        // perhaps introduce a @PluginBuilderAttribute that has no values of its own and uses reflection?
306
307        @PluginBuilderAttribute
308        private String pattern = PatternLayout.DEFAULT_CONVERSION_PATTERN;
309
310        @PluginConfiguration
311        private Configuration configuration = null;
312
313        @PluginElement("Replace")
314        private RegexReplacement regexReplacement = null;
315
316        // LOG4J2-783 use platform default by default
317        @PluginBuilderAttribute
318        private Charset charset = Charset.defaultCharset();
319
320        @PluginBuilderAttribute
321        private boolean alwaysWriteExceptions = true;
322
323        @PluginBuilderAttribute
324        private boolean noConsoleNoAnsi = false;
325
326        @PluginBuilderAttribute
327        private String header = null;
328
329        @PluginBuilderAttribute
330        private String footer = null;
331
332        private Builder() {
333        }
334
335        // TODO: move javadocs from PluginFactory to here
336
337        public Builder withPattern(final String pattern) {
338            this.pattern = pattern;
339            return this;
340        }
341
342
343        public Builder withConfiguration(final Configuration configuration) {
344            this.configuration = configuration;
345            return this;
346        }
347
348        public Builder withRegexReplacement(final RegexReplacement regexReplacement) {
349            this.regexReplacement = regexReplacement;
350            return this;
351        }
352
353        public Builder withCharset(final Charset charset) {
354            this.charset = charset;
355            return this;
356        }
357
358        public Builder withAlwaysWriteExceptions(final boolean alwaysWriteExceptions) {
359            this.alwaysWriteExceptions = alwaysWriteExceptions;
360            return this;
361        }
362
363        public Builder withNoConsoleNoAnsi(final boolean noConsoleNoAnsi) {
364            this.noConsoleNoAnsi = noConsoleNoAnsi;
365            return this;
366        }
367
368        public Builder withHeader(final String header) {
369            this.header = header;
370            return this;
371        }
372
373        public Builder withFooter(final String footer) {
374            this.footer = footer;
375            return this;
376        }
377
378        @Override
379        public PatternLayout build() {
380            // fall back to DefaultConfiguration
381            if (configuration == null) {
382                configuration = new DefaultConfiguration();
383            }
384            return new PatternLayout(configuration, regexReplacement, pattern, charset, alwaysWriteExceptions,
385                noConsoleNoAnsi, header, footer);
386        }
387    }
388}