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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.Charsets;
38  import org.apache.logging.log4j.core.util.Constants;
39  import org.apache.logging.log4j.core.util.Transform;
40  
41  /**
42   * Outputs events as rows in an HTML table on an HTML page.
43   * <p>
44   * Appenders using this layout should have their encoding set to UTF-8 or UTF-16, otherwise events containing non ASCII
45   * characters could result in corrupted log files.
46   * </p>
47   */
48  @Plugin(name = "HtmlLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
49  public final class HtmlLayout extends AbstractStringLayout {
50  
51      private static final long serialVersionUID = 1L;
52  
53      private static final int BUF_SIZE = 256;
54  
55      private static final String TRACE_PREFIX = "<br />&nbsp;&nbsp;&nbsp;&nbsp;";
56  
57      private static final String REGEXP = Constants.LINE_SEPARATOR.equals("\n") ? "\n" : Constants.LINE_SEPARATOR + "|\n";
58  
59      private static final String DEFAULT_TITLE = "Log4j Log Messages";
60  
61      private static final String DEFAULT_CONTENT_TYPE = "text/html";
62  
63      public static final String DEFAULT_FONT_FAMILY = "arial,sans-serif";
64  
65      private final long jvmStartTime = ManagementFactory.getRuntimeMXBean().getStartTime();
66  
67      // Print no location info by default
68      private final boolean locationInfo;
69  
70      private final String title;
71  
72      private final String contentType;
73  
74      /**Possible font sizes */
75      public static enum FontSize {
76          SMALLER("smaller"), XXSMALL("xx-small"), XSMALL("x-small"), SMALL("small"), MEDIUM("medium"), LARGE("large"),
77          XLARGE("x-large"), XXLARGE("xx-large"),  LARGER("larger");
78  
79          private final String size;
80  
81          private FontSize(final String size) {
82              this.size = size;
83          }
84  
85          public String getFontSize() {
86              return size;
87          }
88  
89          public static FontSize getFontSize(final String size) {
90              for (final FontSize fontSize : values()) {
91                  if (fontSize.size.equals(size)) {
92                      return fontSize;
93                  }
94              }
95              return SMALL;
96          }
97  
98          public FontSize larger() {
99              return this.ordinal() < XXLARGE.ordinal() ? FontSize.values()[this.ordinal() + 1] : this;
100         }
101     }
102 
103     private final String font;
104     private final String fontSize;
105     private final String headerSize;
106 
107     private HtmlLayout(final boolean locationInfo, final String title, final String contentType, final Charset charset,
108             final String font, final String fontSize, final String headerSize) {
109         super(charset);
110         this.locationInfo = locationInfo;
111         this.title = title;
112         this.contentType = addCharsetToContentType(contentType);
113         this.font = font;
114         this.fontSize = fontSize;
115         this.headerSize = headerSize;
116     }
117 
118     private String addCharsetToContentType(final String contentType) {
119         if (contentType == null) {
120             return DEFAULT_CONTENT_TYPE + "; charset=" + getCharset();
121         }
122         return contentType.contains("charset") ? contentType : contentType + "; charset=" + getCharset();
123     }
124 
125     /**
126      * Format as a String.
127      *
128      * @param event The Logging Event.
129      * @return A String containing the LogEvent as HTML.
130      */
131     @Override
132     public String toSerializable(final LogEvent event) {
133         final StringBuilder sbuf = new StringBuilder(BUF_SIZE);
134 
135         sbuf.append(Constants.LINE_SEPARATOR).append("<tr>").append(Constants.LINE_SEPARATOR);
136 
137         sbuf.append("<td>");
138         sbuf.append(event.getTimeMillis() - jvmStartTime);
139         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
140 
141         final String escapedThread = Transform.escapeHtmlTags(event.getThreadName());
142         sbuf.append("<td title=\"").append(escapedThread).append(" thread\">");
143         sbuf.append(escapedThread);
144         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
145 
146         sbuf.append("<td title=\"Level\">");
147         if (event.getLevel().equals(Level.DEBUG)) {
148             sbuf.append("<font color=\"#339933\">");
149             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
150             sbuf.append("</font>");
151         } else if (event.getLevel().isMoreSpecificThan(Level.WARN)) {
152             sbuf.append("<font color=\"#993300\"><strong>");
153             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
154             sbuf.append("</strong></font>");
155         } else {
156             sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
157         }
158         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
159 
160         String escapedLogger = Transform.escapeHtmlTags(event.getLoggerName());
161         if (escapedLogger.isEmpty()) {
162             escapedLogger = "root";
163         }
164         sbuf.append("<td title=\"").append(escapedLogger).append(" logger\">");
165         sbuf.append(escapedLogger);
166         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
167 
168         if (locationInfo) {
169             final StackTraceElement element = event.getSource();
170             sbuf.append("<td>");
171             sbuf.append(Transform.escapeHtmlTags(element.getFileName()));
172             sbuf.append(':');
173             sbuf.append(element.getLineNumber());
174             sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
175         }
176 
177         sbuf.append("<td title=\"Message\">");
178         sbuf.append(Transform.escapeHtmlTags(event.getMessage().getFormattedMessage()).replaceAll(REGEXP, "<br />"));
179         sbuf.append("</td>").append(Constants.LINE_SEPARATOR);
180         sbuf.append("</tr>").append(Constants.LINE_SEPARATOR);
181 
182         if (event.getContextStack() != null && !event.getContextStack().isEmpty()) {
183             sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
184             sbuf.append(";\" colspan=\"6\" ");
185             sbuf.append("title=\"Nested Diagnostic Context\">");
186             sbuf.append("NDC: ").append(Transform.escapeHtmlTags(event.getContextStack().toString()));
187             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
188         }
189 
190         if (event.getContextMap() != null && !event.getContextMap().isEmpty()) {
191             sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
192             sbuf.append(";\" colspan=\"6\" ");
193             sbuf.append("title=\"Mapped Diagnostic Context\">");
194             sbuf.append("MDC: ").append(Transform.escapeHtmlTags(event.getContextMap().toString()));
195             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
196         }
197 
198         final Throwable throwable = event.getThrown();
199         if (throwable != null) {
200             sbuf.append("<tr><td bgcolor=\"#993300\" style=\"color:White; font-size : ").append(fontSize);
201             sbuf.append(";\" colspan=\"6\">");
202             appendThrowableAsHtml(throwable, sbuf);
203             sbuf.append("</td></tr>").append(Constants.LINE_SEPARATOR);
204         }
205 
206         return sbuf.toString();
207     }
208 
209     @Override
210     /**
211      * @return The content type.
212      */
213     public String getContentType() {
214         return contentType;
215     }
216 
217     private void appendThrowableAsHtml(final Throwable throwable, final StringBuilder sbuf) {
218         final StringWriter sw = new StringWriter();
219         final PrintWriter pw = new PrintWriter(sw);
220         try {
221             throwable.printStackTrace(pw);
222         } catch (final RuntimeException ex) {
223             // Ignore the exception.
224         }
225         pw.flush();
226         final LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
227         final ArrayList<String> lines = new ArrayList<String>();
228         try {
229           String line = reader.readLine();
230           while (line != null) {
231             lines.add(line);
232             line = reader.readLine();
233           }
234         } catch (final IOException ex) {
235             if (ex instanceof InterruptedIOException) {
236                 Thread.currentThread().interrupt();
237             }
238             lines.add(ex.toString());
239         }
240         boolean first = true;
241         for (final String line : lines) {
242             if (!first) {
243                 sbuf.append(TRACE_PREFIX);
244             } else {
245                 first = false;
246             }
247             sbuf.append(Transform.escapeHtmlTags(line));
248             sbuf.append(Constants.LINE_SEPARATOR);
249         }
250     }
251 
252     /**
253      * Returns appropriate HTML headers.
254      * @return The header as a byte array.
255      */
256     @Override
257     public byte[] getHeader() {
258         final StringBuilder sbuf = new StringBuilder();
259         sbuf.append("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\" ");
260         sbuf.append("\"http://www.w3.org/TR/html4/loose.dtd\">");
261         sbuf.append(Constants.LINE_SEPARATOR);
262         sbuf.append("<html>").append(Constants.LINE_SEPARATOR);
263         sbuf.append("<head>").append(Constants.LINE_SEPARATOR);
264         sbuf.append("<meta charset=\"").append(getCharset()).append("\"/>").append(Constants.LINE_SEPARATOR);
265         sbuf.append("<title>").append(title).append("</title>").append(Constants.LINE_SEPARATOR);
266         sbuf.append("<style type=\"text/css\">").append(Constants.LINE_SEPARATOR);
267         sbuf.append("<!--").append(Constants.LINE_SEPARATOR);
268         sbuf.append("body, table {font-family:").append(font).append("; font-size: ");
269         sbuf.append(headerSize).append(";}").append(Constants.LINE_SEPARATOR);
270         sbuf.append("th {background: #336699; color: #FFFFFF; text-align: left;}").append(Constants.LINE_SEPARATOR);
271         sbuf.append("-->").append(Constants.LINE_SEPARATOR);
272         sbuf.append("</style>").append(Constants.LINE_SEPARATOR);
273         sbuf.append("</head>").append(Constants.LINE_SEPARATOR);
274         sbuf.append("<body bgcolor=\"#FFFFFF\" topmargin=\"6\" leftmargin=\"6\">").append(Constants.LINE_SEPARATOR);
275         sbuf.append("<hr size=\"1\" noshade>").append(Constants.LINE_SEPARATOR);
276         sbuf.append("Log session start time " + new java.util.Date() + "<br>").append(Constants.LINE_SEPARATOR);
277         sbuf.append("<br>").append(Constants.LINE_SEPARATOR);
278         sbuf.append(
279             "<table cellspacing=\"0\" cellpadding=\"4\" border=\"1\" bordercolor=\"#224466\" width=\"100%\">");
280         sbuf.append(Constants.LINE_SEPARATOR);
281         sbuf.append("<tr>").append(Constants.LINE_SEPARATOR);
282         sbuf.append("<th>Time</th>").append(Constants.LINE_SEPARATOR);
283         sbuf.append("<th>Thread</th>").append(Constants.LINE_SEPARATOR);
284         sbuf.append("<th>Level</th>").append(Constants.LINE_SEPARATOR);
285         sbuf.append("<th>Logger</th>").append(Constants.LINE_SEPARATOR);
286         if (locationInfo) {
287             sbuf.append("<th>File:Line</th>").append(Constants.LINE_SEPARATOR);
288         }
289         sbuf.append("<th>Message</th>").append(Constants.LINE_SEPARATOR);
290         sbuf.append("</tr>").append(Constants.LINE_SEPARATOR);
291         return sbuf.toString().getBytes(getCharset());
292     }
293 
294     /**
295      * Returns the appropriate HTML footers.
296      * @return the footer as a byet array.
297      */
298     @Override
299     public byte[] getFooter() {
300         final StringBuilder sbuf = new StringBuilder();
301         sbuf.append("</table>").append(Constants.LINE_SEPARATOR);
302         sbuf.append("<br>").append(Constants.LINE_SEPARATOR);
303         sbuf.append("</body></html>");
304         return sbuf.toString().getBytes(getCharset());
305     }
306 
307     /**
308      * Create an HTML Layout.
309      * @param locationInfo If "true", location information will be included. The default is false.
310      * @param title The title to include in the file header. If none is specified the default title will be used.
311      * @param contentType The content type. Defaults to "text/html".
312      * @param charset The character set to use. If not specified, the default will be used.
313      * @param fontSize The font size of the text.
314      * @param font The font to use for the text.
315      * @return An HTML Layout.
316      */
317     @PluginFactory
318     public static HtmlLayout createLayout(
319             @PluginAttribute(value = "locationInfo", defaultBoolean = false) final boolean locationInfo,
320             @PluginAttribute(value = "title", defaultString = DEFAULT_TITLE) final String title,
321             @PluginAttribute("contentType") String contentType,
322             @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
323             @PluginAttribute("fontSize") String fontSize,
324             @PluginAttribute(value = "fontName", defaultString = DEFAULT_FONT_FAMILY) final String font) {
325         final FontSize fs = FontSize.getFontSize(fontSize);
326         fontSize = fs.getFontSize();
327         final String headerSize = fs.larger().getFontSize();
328         if (contentType == null) {
329             contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
330         }
331         return new HtmlLayout(locationInfo, title, contentType, charset, font, fontSize, headerSize);
332     }
333 
334     /**
335      * Creates an HTML Layout using the default settings.
336      *
337      * @return an HTML Layout.
338      */
339     public static HtmlLayout createDefaultLayout() {
340         return newBuilder().build();
341     }
342 
343     @PluginBuilderFactory
344     public static Builder newBuilder() {
345         return new Builder();
346     }
347 
348     public static class Builder implements org.apache.logging.log4j.core.util.Builder<HtmlLayout> {
349 
350         @PluginBuilderAttribute
351         private boolean locationInfo = false;
352 
353         @PluginBuilderAttribute
354         private String title = DEFAULT_TITLE;
355 
356         @PluginBuilderAttribute
357         private String contentType = null; // defer default value in order to use specified charset
358 
359         @PluginBuilderAttribute
360         private Charset charset = Charsets.UTF_8;
361 
362         @PluginBuilderAttribute
363         private FontSize fontSize = FontSize.SMALL;
364 
365         @PluginBuilderAttribute
366         private String fontName = DEFAULT_FONT_FAMILY;
367 
368         private Builder() {
369         }
370 
371         public Builder withLocationInfo(final boolean locationInfo) {
372             this.locationInfo = locationInfo;
373             return this;
374         }
375 
376         public Builder withTitle(final String title) {
377             this.title = title;
378             return this;
379         }
380 
381         public Builder withContentType(final String contentType) {
382             this.contentType = contentType;
383             return this;
384         }
385 
386         public Builder withCharset(final Charset charset) {
387             this.charset = charset;
388             return this;
389         }
390 
391         public Builder withFontSize(final FontSize fontSize) {
392             this.fontSize = fontSize;
393             return this;
394         }
395 
396         public Builder withFontName(final String fontName) {
397             this.fontName = fontName;
398             return this;
399         }
400 
401         @Override
402         public HtmlLayout build() {
403             // TODO: extract charset from content-type
404             if (contentType == null) {
405                 contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
406             }
407             return new HtmlLayout(locationInfo, title, contentType, charset, fontName, fontSize.getFontSize(),
408                 fontSize.larger().getFontSize());
409         }
410     }
411 }