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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  package org.apache.logging.log4j.core.layout;
18  
19  import java.io.IOException;
20  import java.io.InterruptedIOException;
21  import java.io.LineNumberReader;
22  import java.io.PrintWriter;
23  import java.io.StringReader;
24  import java.io.StringWriter;
25  import java.lang.management.ManagementFactory;
26  import java.nio.charset.Charset;
27  import java.util.ArrayList;
28  import org.apache.logging.log4j.Level;
29  import org.apache.logging.log4j.core.Layout;
30  import org.apache.logging.log4j.core.LogEvent;
31  import org.apache.logging.log4j.core.config.Node;
32  import org.apache.logging.log4j.core.config.plugins.Plugin;
33  import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
34  import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
35  import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
36  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
37  import org.apache.logging.log4j.core.util.Constants;
38  import org.apache.logging.log4j.core.util.Transform;
39  
40  /**
41   * Outputs events as rows in an HTML table on an HTML page.
42   * <p>
43   * Appenders using this layout should have their encoding set to UTF-8 or UTF-16, otherwise events containing non ASCII
44   * characters could result in corrupted log files.
45   * </p>
46   */
47  @Plugin(name = "HtmlLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
48  public final class HtmlLayout extends AbstractStringLayout {
49  
50      private static final long serialVersionUID = 1L;
51  
52      private static final int BUF_SIZE = 256;
53  
54      private static final String TRACE_PREFIX = "<br />&nbsp;&nbsp;&nbsp;&nbsp;";
55  
56      private static final String REGEXP = Constants.LINE_SEPARATOR.equals("\n") ? "\n" : Constants.LINE_SEPARATOR + "|\n";
57  
58      private static final String DEFAULT_TITLE = "Log4j Log Messages";
59  
60      private static final String DEFAULT_CONTENT_TYPE = "text/html";
61  
62      public static final String DEFAULT_FONT_FAMILY = "arial,sans-serif";
63  
64      private final long jvmStartTime = ManagementFactory.getRuntimeMXBean().getStartTime();
65  
66      // Print no location info by default
67      private final boolean locationInfo;
68  
69      private final String title;
70  
71      private final String contentType;
72  
73      /**Possible font sizes */
74      public static enum FontSize {
75          SMALLER("smaller"), XXSMALL("xx-small"), XSMALL("x-small"), SMALL("small"), MEDIUM("medium"), LARGE("large"),
76          XLARGE("x-large"), XXLARGE("xx-large"),  LARGER("larger");
77  
78          private final String size;
79  
80          private FontSize(final String size) {
81              this.size = size;
82          }
83  
84          public String getFontSize() {
85              return size;
86          }
87  
88          public static FontSize getFontSize(final String size) {
89              for (final FontSize fontSize : values()) {
90                  if (fontSize.size.equals(size)) {
91                      return fontSize;
92                  }
93              }
94              return SMALL;
95          }
96  
97          public FontSize larger() {
98              return this.ordinal() < XXLARGE.ordinal() ? FontSize.values()[this.ordinal() + 1] : this;
99          }
100     }
101 
102     private final String font;
103     private final String fontSize;
104     private final String headerSize;
105 
106     private HtmlLayout(final boolean locationInfo, final String title, final String contentType, final Charset charset,
107             final String font, final String fontSize, final String headerSize) {
108         super(charset);
109         this.locationInfo = locationInfo;
110         this.title = title;
111         this.contentType = addCharsetToContentType(contentType);
112         this.font = font;
113         this.fontSize = fontSize;
114         this.headerSize = headerSize;
115     }
116 
117     private String addCharsetToContentType(final String contentType) {
118         if (contentType == null) {
119             return DEFAULT_CONTENT_TYPE + "; charset=" + getCharset();
120         }
121         return contentType.contains("charset") ? contentType : contentType + "; charset=" + getCharset();
122     }
123 
124     /**
125      * Format as a String.
126      *
127      * @param event The Logging Event.
128      * @return A String containing the LogEvent as HTML.
129      */
130     @Override
131     public String toSerializable(final LogEvent event) {
132         final StringBuilder sbuf = new StringBuilder(BUF_SIZE);
133 
134         sbuf.append(Constants.LINE_SEPARATOR).append("<tr>").append(Constants.LINE_SEPARATOR);
135 
136         sbuf.append("<td>");
137         sbuf.append(event.getTimeMillis() - jvmStartTime);
138         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
139 
140         final String escapedThread = Transform.escapeHtmlTags(event.getThreadName());
141         sbuf.append("<td title=\"").append(escapedThread).append(" thread\">");
142         sbuf.append(escapedThread);
143         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
144 
145         sbuf.append("<td title=\"Level\">");
146         if (event.getLevel().equals(Level.DEBUG)) {
147             sbuf.append("<font color=\"#339933\">");
148             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
149             sbuf.append("</font>");
150         } else if (event.getLevel().isMoreSpecificThan(Level.WARN)) {
151             sbuf.append("<font color=\"#993300\"><strong>");
152             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
153             sbuf.append("</strong></font>");
154         } else {
155             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
156         }
157         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
158 
159         String escapedLogger = Transform.escapeHtmlTags(event.getLoggerName());
160         if (escapedLogger.isEmpty()) {
161             escapedLogger = "root";
162         }
163         sbuf.append("<td title=\"").append(escapedLogger).append(" logger\">");
164         sbuf.append(escapedLogger);
165         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
166 
167         if (locationInfo) {
168             final StackTraceElement element = event.getSource();
169             sbuf.append("<td>");
170             sbuf.append(Transform.escapeHtmlTags(element.getFileName()));
171             sbuf.append(':');
172             sbuf.append(element.getLineNumber());
173             sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
174         }
175 
176         sbuf.append("<td title=\"Message\">");
177         sbuf.append(Transform.escapeHtmlTags(event.getMessage().getFormattedMessage()).replaceAll(REGEXP, "<br />"));
178         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
179         sbuf.append("</tr>").append(Constants.LINE_SEPARATOR);
180 
181         if (event.getContextStack() != null && !event.getContextStack().isEmpty()) {
182             sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
183             sbuf.append(";\" colspan=\"6\" ");
184             sbuf.append("title=\"Nested Diagnostic Context\">");
185             sbuf.append("NDC: ").append(Transform.escapeHtmlTags(event.getContextStack().toString()));
186             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
187         }
188 
189         if (event.getContextMap() != null && !event.getContextMap().isEmpty()) {
190             sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
191             sbuf.append(";\" colspan=\"6\" ");
192             sbuf.append("title=\"Mapped Diagnostic Context\">");
193             sbuf.append("MDC: ").append(Transform.escapeHtmlTags(event.getContextMap().toString()));
194             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
195         }
196 
197         final Throwable throwable = event.getThrown();
198         if (throwable != null) {
199             sbuf.append("<tr><td bgcolor=\"#993300\" style=\"color:White; font-size : ").append(fontSize);
200             sbuf.append(";\" colspan=\"6\">");
201             appendThrowableAsHtml(throwable, sbuf);
202             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
203         }
204 
205         return sbuf.toString();
206     }
207 
208     @Override
209     /**
210      * @return The content type.
211      */
212     public String getContentType() {
213         return contentType;
214     }
215 
216     private void appendThrowableAsHtml(final Throwable throwable, final StringBuilder sbuf) {
217         final StringWriter sw = new StringWriter();
218         final PrintWriter pw = new PrintWriter(sw);
219         try {
220             throwable.printStackTrace(pw);
221         } catch (final RuntimeException ex) {
222             // Ignore the exception.
223         }
224         pw.flush();
225         final LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
226         final ArrayList<String> lines = new ArrayList<String>();
227         try {
228           String line = reader.readLine();
229           while (line != null) {
230             lines.add(line);
231             line = reader.readLine();
232           }
233         } catch (final IOException ex) {
234             if (ex instanceof InterruptedIOException) {
235                 Thread.currentThread().interrupt();
236             }
237             lines.add(ex.toString());
238         }
239         boolean first = true;
240         for (final String line : lines) {
241             if (!first) {
242                 sbuf.append(TRACE_PREFIX);
243             } else {
244                 first = false;
245             }
246             sbuf.append(Transform.escapeHtmlTags(line));
247             sbuf.append(Constants.LINE_SEPARATOR);
248         }
249     }
250 
251     /**
252      * Returns appropriate HTML headers.
253      * @return The header as a byte array.
254      */
255     @Override
256     public byte[] getHeader() {
257         final StringBuilder sbuf = new StringBuilder();
258         sbuf.append("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\" ");
259         sbuf.append("\"http://www.w3.org/TR/html4/loose.dtd\">");
260         sbuf.append(Constants.LINE_SEPARATOR);
261         sbuf.append("<html>").append(Constants.LINE_SEPARATOR);
262         sbuf.append("<head>").append(Constants.LINE_SEPARATOR);
263         sbuf.append("<meta charset=\"").append(getCharset()).append("\"/>").append(Constants.LINE_SEPARATOR);
264         sbuf.append("<title>").append(title).append("</title>").append(Constants.LINE_SEPARATOR);
265         sbuf.append("<style type=\"text/css\">").append(Constants.LINE_SEPARATOR);
266         sbuf.append("<!--").append(Constants.LINE_SEPARATOR);
267         sbuf.append("body, table {font-family:").append(font).append("; font-size: ");
268         sbuf.append(headerSize).append(";}").append(Constants.LINE_SEPARATOR);
269         sbuf.append("th {background: #336699; color: #FFFFFF; text-align: left;}").append(Constants.LINE_SEPARATOR);
270         sbuf.append("-->").append(Constants.LINE_SEPARATOR);
271         sbuf.append("</style>").append(Constants.LINE_SEPARATOR);
272         sbuf.append("</head>").append(Constants.LINE_SEPARATOR);
273         sbuf.append("<body bgcolor=\"#FFFFFF\" topmargin=\"6\" leftmargin=\"6\">").append(Constants.LINE_SEPARATOR);
274         sbuf.append("<hr size=\"1\" noshade=\"noshade\">").append(Constants.LINE_SEPARATOR);
275         sbuf.append("Log session start time " + new java.util.Date() + "<br>").append(Constants.LINE_SEPARATOR);
276         sbuf.append("<br>").append(Constants.LINE_SEPARATOR);
277         sbuf.append(
278             "<table cellspacing=\"0\" cellpadding=\"4\" border=\"1\" bordercolor=\"#224466\" width=\"100%\">");
279         sbuf.append(Constants.LINE_SEPARATOR);
280         sbuf.append("<tr>").append(Constants.LINE_SEPARATOR);
281         sbuf.append("<th>Time</th>").append(Constants.LINE_SEPARATOR);
282         sbuf.append("<th>Thread</th>").append(Constants.LINE_SEPARATOR);
283         sbuf.append("<th>Level</th>").append(Constants.LINE_SEPARATOR);
284         sbuf.append("<th>Logger</th>").append(Constants.LINE_SEPARATOR);
285         if (locationInfo) {
286             sbuf.append("<th>File:Line</th>").append(Constants.LINE_SEPARATOR);
287         }
288         sbuf.append("<th>Message</th>").append(Constants.LINE_SEPARATOR);
289         sbuf.append("</tr>").append(Constants.LINE_SEPARATOR);
290         return sbuf.toString().getBytes(getCharset());
291     }
292 
293     /**
294      * Returns the appropriate HTML footers.
295      * @return the footer as a byet array.
296      */
297     @Override
298     public byte[] getFooter() {
299         final StringBuilder sbuf = new StringBuilder();
300         sbuf.append("</table>").append(Constants.LINE_SEPARATOR);
301         sbuf.append("<br>").append(Constants.LINE_SEPARATOR);
302         sbuf.append("</body></html>");
303         return getBytes(sbuf.toString());
304     }
305 
306     /**
307      * Create an HTML Layout.
308      * @param locationInfo If "true", location information will be included. The default is false.
309      * @param title The title to include in the file header. If none is specified the default title will be used.
310      * @param contentType The content type. Defaults to "text/html".
311      * @param charset The character set to use. If not specified, the default will be used.
312      * @param fontSize The font size of the text.
313      * @param font The font to use for the text.
314      * @return An HTML Layout.
315      */
316     @PluginFactory
317     public static HtmlLayout createLayout(
318             @PluginAttribute(value = "locationInfo", defaultBoolean = false) final boolean locationInfo,
319             @PluginAttribute(value = "title", defaultString = DEFAULT_TITLE) final String title,
320             @PluginAttribute("contentType") String contentType,
321             @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
322             @PluginAttribute("fontSize") String fontSize,
323             @PluginAttribute(value = "fontName", defaultString = DEFAULT_FONT_FAMILY) final String font) {
324         final FontSize fs = FontSize.getFontSize(fontSize);
325         fontSize = fs.getFontSize();
326         final String headerSize = fs.larger().getFontSize();
327         if (contentType == null) {
328             contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
329         }
330         return new HtmlLayout(locationInfo, title, contentType, charset, font, fontSize, headerSize);
331     }
332 
333     /**
334      * Creates an HTML Layout using the default settings.
335      *
336      * @return an HTML Layout.
337      */
338     public static HtmlLayout createDefaultLayout() {
339         return newBuilder().build();
340     }
341 
342     @PluginBuilderFactory
343     public static Builder newBuilder() {
344         return new Builder();
345     }
346 
347     public static class Builder implements org.apache.logging.log4j.core.util.Builder<HtmlLayout> {
348 
349         @PluginBuilderAttribute
350         private boolean locationInfo = false;
351 
352         @PluginBuilderAttribute
353         private String title = DEFAULT_TITLE;
354 
355         @PluginBuilderAttribute
356         private String contentType = null; // defer default value in order to use specified charset
357 
358         @PluginBuilderAttribute
359         private Charset charset = Constants.UTF_8;
360 
361         @PluginBuilderAttribute
362         private FontSize fontSize = FontSize.SMALL;
363 
364         @PluginBuilderAttribute
365         private String fontName = DEFAULT_FONT_FAMILY;
366 
367         private Builder() {
368         }
369 
370         public Builder withLocationInfo(final boolean locationInfo) {
371             this.locationInfo = locationInfo;
372             return this;
373         }
374 
375         public Builder withTitle(final String title) {
376             this.title = title;
377             return this;
378         }
379 
380         public Builder withContentType(final String contentType) {
381             this.contentType = contentType;
382             return this;
383         }
384 
385         public Builder withCharset(final Charset charset) {
386             this.charset = charset;
387             return this;
388         }
389 
390         public Builder withFontSize(final FontSize fontSize) {
391             this.fontSize = fontSize;
392             return this;
393         }
394 
395         public Builder withFontName(final String fontName) {
396             this.fontName = fontName;
397             return this;
398         }
399 
400         @Override
401         public HtmlLayout build() {
402             // TODO: extract charset from content-type
403             if (contentType == null) {
404                 contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
405             }
406             return new HtmlLayout(locationInfo, title, contentType, charset, fontName, fontSize.getFontSize(),
407                 fontSize.larger().getFontSize());
408         }
409     }
410 }