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.util.HashMap;
021    import java.util.List;
022    import java.util.Map;
023    
024    import org.apache.logging.log4j.core.LogEvent;
025    import org.apache.logging.log4j.core.config.Configuration;
026    import org.apache.logging.log4j.core.config.DefaultConfiguration;
027    import org.apache.logging.log4j.core.config.plugins.Plugin;
028    import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
029    import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
030    import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
031    import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
032    import org.apache.logging.log4j.core.config.plugins.PluginElement;
033    import org.apache.logging.log4j.core.config.plugins.PluginFactory;
034    import org.apache.logging.log4j.core.pattern.LogEventPatternConverter;
035    import org.apache.logging.log4j.core.pattern.PatternFormatter;
036    import org.apache.logging.log4j.core.pattern.PatternParser;
037    import org.apache.logging.log4j.core.pattern.RegexReplacement;
038    import org.apache.logging.log4j.core.util.Charsets;
039    import org.apache.logging.log4j.core.util.OptionConverter;
040    
041    /**
042     * <p>A flexible layout configurable with pattern string. The goal of this class
043     * is to {@link org.apache.logging.log4j.core.Layout#toByteArray format} a {@link LogEvent} and return the results.
044     * The format of the result depends on the <em>conversion pattern</em>.
045     * <p>
046     * <p/>
047     * <p>The conversion pattern is closely related to the conversion
048     * pattern of the printf function in C. A conversion pattern is
049     * composed of literal text and format control expressions called
050     * <em>conversion specifiers</em>.
051     *
052     * See the Log4j Manual for details on the supported pattern converters.
053     */
054    @Plugin(name = "PatternLayout", category = "Core", elementType = "layout", printObject = true)
055    public final class PatternLayout extends AbstractStringLayout {
056        /**
057         * Default pattern string for log output. Currently set to the
058         * string <b>"%m%n"</b> which just prints the application supplied
059         * message.
060         */
061        public static final String DEFAULT_CONVERSION_PATTERN = "%m%n";
062    
063        /**
064         * A conversion pattern equivalent to the TTCCCLayout.
065         * Current value is <b>%r [%t] %p %c %x - %m%n</b>.
066         */
067        public static final String TTCC_CONVERSION_PATTERN =
068            "%r [%t] %p %c %x - %m%n";
069    
070        /**
071         * A simple pattern.
072         * Current value is <b>%d [%t] %p %c - %m%n</b>.
073         */
074        public static final String SIMPLE_CONVERSION_PATTERN =
075            "%d [%t] %p %c - %m%n";
076    
077        /** Key to identify pattern converters. */
078        public static final String KEY = "Converter";
079    
080        /**
081         * Initial converter for pattern.
082         */
083        private List<PatternFormatter> formatters;
084    
085        /**
086         * Conversion pattern.
087         */
088        private final String conversionPattern;
089    
090    
091        /**
092         * The current Configuration.
093         */
094        private final Configuration config;
095    
096        private final RegexReplacement replace;
097    
098        private final boolean alwaysWriteExceptions;
099    
100        private final boolean noConsoleNoAnsi;
101    
102        /**
103         * Constructs a EnhancedPatternLayout using the supplied conversion pattern.
104         *
105         * @param config The Configuration.
106         * @param replace The regular expression to match.
107         * @param pattern conversion pattern.
108         * @param charset The character set.
109         * @param alwaysWriteExceptions Whether or not exceptions should always be handled in this pattern (if {@code true},
110         *                         exceptions will be written even if the pattern does not specify so).
111         * @param noConsoleNoAnsi
112         *            If {@code "true"} (default) and {@link System#console()} is null, do not output ANSI escape codes
113         * @param header
114         */
115        private PatternLayout(final Configuration config, final RegexReplacement replace, final String pattern,
116                              final Charset charset, final boolean alwaysWriteExceptions, boolean noConsoleNoAnsi,
117                              String header, String footer) {
118            super(charset);
119            this.replace = replace;
120            this.conversionPattern = pattern;
121            this.config = config;
122            this.alwaysWriteExceptions = alwaysWriteExceptions;
123            this.noConsoleNoAnsi = noConsoleNoAnsi;
124            final PatternParser parser = createPatternParser(config);
125            this.formatters = parser.parse(pattern == null ? DEFAULT_CONVERSION_PATTERN : pattern, this.alwaysWriteExceptions, this.noConsoleNoAnsi);
126            if (charset != null) {
127                if (header != null) {
128                    setHeader(header.getBytes(charset));
129                }
130                if (footer != null) {
131                    setFooter(footer.getBytes(charset));
132                }
133            } else {
134                if (header != null) {
135                    setHeader(header.getBytes());
136                }
137                if (footer != null) {
138                    setFooter(footer.getBytes());
139                }
140            }
141        }
142    
143        private byte[] strSubstitutorReplace(final byte... b) {
144            if (b != null && config != null) {
145                final Charset cs = getCharset();
146                return config.getStrSubstitutor().replace(new String(b, cs)).getBytes(cs);
147            }
148            return b;
149        }
150    
151        @Override
152        public byte[] getHeader() {
153            return strSubstitutorReplace(super.getHeader());
154        }
155    
156        @Override
157        public byte[] getFooter() {
158            return strSubstitutorReplace(super.getFooter());
159        }
160    
161        /**
162         * Set the <b>ConversionPattern</b> option. This is the string which
163         * controls formatting and consists of a mix of literal content and
164         * conversion specifiers.
165         *
166         * @param conversionPattern conversion pattern.
167         */
168        public void setConversionPattern(final String conversionPattern) {
169            final String pattern = OptionConverter.convertSpecialChars(conversionPattern);
170            if (pattern == null) {
171                return;
172            }
173            final PatternParser parser = createPatternParser(this.config);
174            formatters = parser.parse(pattern, this.alwaysWriteExceptions, this.noConsoleNoAnsi);
175        }
176    
177        /**
178         * Gets the conversion pattern.
179         *
180         * @return the conversion pattern.
181         */
182        public String getConversionPattern() {
183            return conversionPattern;
184        }
185    
186        /**
187         * PatternLayout's content format is specified by:<p/>
188         * Key: "structured" Value: "false"<p/>
189         * Key: "formatType" Value: "conversion" (format uses the keywords supported by OptionConverter)<p/>
190         * Key: "format" Value: provided "conversionPattern" param
191         * @return Map of content format keys supporting PatternLayout
192         */
193        @Override
194        public Map<String, String> getContentFormat()
195        {
196            final Map<String, String> result = new HashMap<String, String>();
197            result.put("structured", "false");
198            result.put("formatType", "conversion");
199            result.put("format", conversionPattern);
200            return result;
201        }
202    
203        /**
204         * Formats a logging event to a writer.
205         *
206         *
207         * @param event logging event to be formatted.
208         * @return The event formatted as a String.
209         */
210        @Override
211        public String toSerializable(final LogEvent event) {
212            final StringBuilder buf = new StringBuilder();
213            for (final PatternFormatter formatter : formatters) {
214                formatter.format(event, buf);
215            }
216            String str = buf.toString();
217            if (replace != null) {
218                str = replace.format(str);
219            }
220            return str;
221        }
222    
223        /**
224         * Create a PatternParser.
225         * @param config The Configuration.
226         * @return The PatternParser.
227         */
228        public static PatternParser createPatternParser(final Configuration config) {
229            if (config == null) {
230                return new PatternParser(config, KEY, LogEventPatternConverter.class);
231            }
232            PatternParser parser = config.getComponent(KEY);
233            if (parser == null) {
234                parser = new PatternParser(config, KEY, LogEventPatternConverter.class);
235                config.addComponent(KEY, parser);
236                parser = (PatternParser) config.getComponent(KEY);
237            }
238            return parser;
239        }
240    
241        @Override
242        public String toString() {
243            return conversionPattern;
244        }
245    
246        /**
247         * Create a pattern layout.
248         *
249         * @param pattern
250         *        The pattern. If not specified, defaults to DEFAULT_CONVERSION_PATTERN.
251         * @param config
252         *        The Configuration. Some Converters require access to the Interpolator.
253         * @param replace
254         *        A Regex replacement String.
255         * @param charset
256         *        The character set.
257         * @param alwaysWriteExceptions
258         *        If {@code "true"} (default) exceptions are always written even if the pattern contains no exception tokens.
259         * @param noConsoleNoAnsi
260         *        If {@code "true"} (default is false) and {@link System#console()} is null, do not output ANSI escape codes
261         * @param header
262         *        The footer to place at the end of the document, once.
263         * @param footer
264         *        The footer to place at the top of the document, once.
265         * @return The PatternLayout.
266         */
267        @PluginFactory
268        public static PatternLayout createLayout(
269                @PluginAttribute(value = "pattern", defaultString = DEFAULT_CONVERSION_PATTERN) final String pattern,
270                @PluginConfiguration final Configuration config,
271                @PluginElement("Replace") final RegexReplacement replace,
272                @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
273                @PluginAttribute(value = "alwaysWriteExceptions", defaultBoolean = true) final boolean alwaysWriteExceptions,
274                @PluginAttribute(value = "noConsoleNoAnsi", defaultBoolean = false) final boolean noConsoleNoAnsi,
275                @PluginAttribute("header") final String header,
276                @PluginAttribute("footer") final String footer) {
277            return newBuilder()
278                .withPattern(pattern)
279                .withConfiguration(config)
280                .withRegexReplacement(replace)
281                .withCharset(charset)
282                .withAlwaysWriteExceptions(alwaysWriteExceptions)
283                .withNoConsoleNoAnsi(noConsoleNoAnsi)
284                .withHeader(header)
285                .withFooter(footer)
286                .build();
287        }
288    
289        /**
290         * Creates a PatternLayout using the default options. These options include using UTF-8, the default conversion
291         * pattern, exceptions being written, and with ANSI escape codes.
292         *
293         * @return the PatternLayout.
294         * @see #DEFAULT_CONVERSION_PATTERN Default conversion pattern
295         */
296        public static PatternLayout createDefaultLayout() {
297            return newBuilder().build();
298        }
299    
300        /**
301         * Creates a builder for a custom PatternLayout.
302         * @return a PatternLayout builder.
303         */
304        @PluginBuilderFactory
305        public static Builder newBuilder() {
306            return new Builder();
307        }
308    
309        /**
310         * Custom PatternLayout builder. Use the {@link PatternLayout#newBuilder() builder factory method} to create this.
311         */
312        public static class Builder implements org.apache.logging.log4j.core.util.Builder<PatternLayout> {
313    
314            // FIXME: it seems rather redundant to repeat default values (same goes for field names)
315            // perhaps introduce a @PluginBuilderAttribute that has no values of its own and uses reflection?
316    
317            @PluginBuilderAttribute
318            private String pattern = PatternLayout.DEFAULT_CONVERSION_PATTERN;
319    
320            @PluginConfiguration
321            private Configuration configuration = null;
322    
323            @PluginElement("Replace")
324            private RegexReplacement regexReplacement = null;
325    
326            @PluginBuilderAttribute
327            private Charset charset = Charsets.UTF_8;
328    
329            @PluginBuilderAttribute
330            private boolean alwaysWriteExceptions = true;
331    
332            @PluginBuilderAttribute
333            private boolean noConsoleNoAnsi = false;
334    
335            @PluginBuilderAttribute
336            private String header = null;
337    
338            @PluginBuilderAttribute
339            private String footer = null;
340    
341            private Builder() {
342            }
343    
344            // TODO: move javadocs from PluginFactory to here
345    
346            public Builder withPattern(final String pattern) {
347                this.pattern = pattern;
348                return this;
349            }
350    
351    
352            public Builder withConfiguration(final Configuration configuration) {
353                this.configuration = configuration;
354                return this;
355            }
356    
357            public Builder withRegexReplacement(final RegexReplacement regexReplacement) {
358                this.regexReplacement = regexReplacement;
359                return this;
360            }
361    
362            public Builder withCharset(final Charset charset) {
363                this.charset = charset;
364                return this;
365            }
366    
367            public Builder withAlwaysWriteExceptions(final boolean alwaysWriteExceptions) {
368                this.alwaysWriteExceptions = alwaysWriteExceptions;
369                return this;
370            }
371    
372            public Builder withNoConsoleNoAnsi(final boolean noConsoleNoAnsi) {
373                this.noConsoleNoAnsi = noConsoleNoAnsi;
374                return this;
375            }
376    
377            public Builder withHeader(final String header) {
378                this.header = header;
379                return this;
380            }
381    
382            public Builder withFooter(final String footer) {
383                this.footer = footer;
384                return this;
385            }
386    
387            @Override
388            public PatternLayout build() {
389                // fall back to DefaultConfiguration
390                if (configuration == null) {
391                    configuration = new DefaultConfiguration();
392                }
393                return new PatternLayout(configuration, regexReplacement, pattern, charset, alwaysWriteExceptions,
394                    noConsoleNoAnsi, header, footer);
395            }
396        }
397    }