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.io.IOException;
020import java.io.InterruptedIOException;
021import java.io.LineNumberReader;
022import java.io.PrintWriter;
023import java.io.StringReader;
024import java.io.StringWriter;
025import java.lang.management.ManagementFactory;
026import java.nio.charset.Charset;
027import java.nio.charset.StandardCharsets;
028import java.util.ArrayList;
029
030import org.apache.logging.log4j.Level;
031import org.apache.logging.log4j.core.Layout;
032import org.apache.logging.log4j.core.LogEvent;
033import org.apache.logging.log4j.core.config.LoggerConfig;
034import org.apache.logging.log4j.core.config.Node;
035import org.apache.logging.log4j.core.config.plugins.Plugin;
036import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
037import org.apache.logging.log4j.core.config.plugins.PluginBuilderAttribute;
038import org.apache.logging.log4j.core.config.plugins.PluginBuilderFactory;
039import org.apache.logging.log4j.core.config.plugins.PluginFactory;
040import org.apache.logging.log4j.core.util.Transform;
041import org.apache.logging.log4j.util.Strings;
042
043/**
044 * Outputs events as rows in an HTML table on an HTML page.
045 * <p>
046 * Appenders using this layout should have their encoding set to UTF-8 or UTF-16, otherwise events containing non ASCII
047 * characters could result in corrupted log files.
048 * </p>
049 */
050@Plugin(name = "HtmlLayout", category = Node.CATEGORY, elementType = Layout.ELEMENT_TYPE, printObject = true)
051public final class HtmlLayout extends AbstractStringLayout {
052
053    /**
054     * Default font family: {@value}.
055     */
056    public static final String DEFAULT_FONT_FAMILY = "arial,sans-serif";
057
058    private static final String TRACE_PREFIX = "<br />&nbsp;&nbsp;&nbsp;&nbsp;";
059    private static final String REGEXP = Strings.LINE_SEPARATOR.equals("\n") ? "\n" : Strings.LINE_SEPARATOR + "|\n";
060    private static final String DEFAULT_TITLE = "Log4j Log Messages";
061    private static final String DEFAULT_CONTENT_TYPE = "text/html";
062
063    private final long jvmStartTime = ManagementFactory.getRuntimeMXBean().getStartTime();
064
065    // Print no location info by default
066    private final boolean locationInfo;
067    private final String title;
068    private final String contentType;
069    private final String font;
070    private final String fontSize;
071    private final String headerSize;
072
073    /**Possible font sizes */
074    public static enum FontSize {
075        SMALLER("smaller"), XXSMALL("xx-small"), XSMALL("x-small"), SMALL("small"), MEDIUM("medium"), LARGE("large"),
076        XLARGE("x-large"), XXLARGE("xx-large"),  LARGER("larger");
077
078        private final String size;
079
080        private FontSize(final String size) {
081            this.size = size;
082        }
083
084        public String getFontSize() {
085            return size;
086        }
087
088        public static FontSize getFontSize(final String size) {
089            for (final FontSize fontSize : values()) {
090                if (fontSize.size.equals(size)) {
091                    return fontSize;
092                }
093            }
094            return SMALL;
095        }
096
097        public FontSize larger() {
098            return this.ordinal() < XXLARGE.ordinal() ? FontSize.values()[this.ordinal() + 1] : this;
099        }
100    }
101
102    private HtmlLayout(final boolean locationInfo, final String title, final String contentType, final Charset charset,
103            final String font, final String fontSize, final String headerSize) {
104        super(charset);
105        this.locationInfo = locationInfo;
106        this.title = title;
107        this.contentType = addCharsetToContentType(contentType);
108        this.font = font;
109        this.fontSize = fontSize;
110        this.headerSize = headerSize;
111    }
112
113    /**
114     * For testing purposes.
115     */
116    public String getTitle() {
117        return title;
118    }
119
120    /**
121     * For testing purposes.
122     */
123    public boolean isLocationInfo() {
124        return locationInfo;
125    }
126
127    private String addCharsetToContentType(final String contentType) {
128        if (contentType == null) {
129            return DEFAULT_CONTENT_TYPE + "; charset=" + getCharset();
130        }
131        return contentType.contains("charset") ? contentType : contentType + "; charset=" + getCharset();
132    }
133
134    /**
135     * Formats as a String.
136     *
137     * @param event The Logging Event.
138     * @return A String containing the LogEvent as HTML.
139     */
140    @Override
141    public String toSerializable(final LogEvent event) {
142        final StringBuilder sbuf = getStringBuilder();
143
144        sbuf.append(Strings.LINE_SEPARATOR).append("<tr>").append(Strings.LINE_SEPARATOR);
145
146        sbuf.append("<td>");
147        sbuf.append(event.getTimeMillis() - jvmStartTime);
148        sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
149
150        final String escapedThread = Transform.escapeHtmlTags(event.getThreadName());
151        sbuf.append("<td title=\"").append(escapedThread).append(" thread\">");
152        sbuf.append(escapedThread);
153        sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
154
155        sbuf.append("<td title=\"Level\">");
156        if (event.getLevel().equals(Level.DEBUG)) {
157            sbuf.append("<font color=\"#339933\">");
158            sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
159            sbuf.append("</font>");
160        } else if (event.getLevel().isMoreSpecificThan(Level.WARN)) {
161            sbuf.append("<font color=\"#993300\"><strong>");
162            sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
163            sbuf.append("</strong></font>");
164        } else {
165            sbuf.append(Transform.escapeHtmlTags(String.valueOf(event.getLevel())));
166        }
167        sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
168
169        String escapedLogger = Transform.escapeHtmlTags(event.getLoggerName());
170        if (Strings.isEmpty(escapedLogger)) {
171            escapedLogger = LoggerConfig.ROOT;
172        }
173        sbuf.append("<td title=\"").append(escapedLogger).append(" logger\">");
174        sbuf.append(escapedLogger);
175        sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
176
177        if (locationInfo) {
178            final StackTraceElement element = event.getSource();
179            sbuf.append("<td>");
180            sbuf.append(Transform.escapeHtmlTags(element.getFileName()));
181            sbuf.append(':');
182            sbuf.append(element.getLineNumber());
183            sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
184        }
185
186        sbuf.append("<td title=\"Message\">");
187        sbuf.append(Transform.escapeHtmlTags(event.getMessage().getFormattedMessage()).replaceAll(REGEXP, "<br />"));
188        sbuf.append("</td>").append(Strings.LINE_SEPARATOR);
189        sbuf.append("</tr>").append(Strings.LINE_SEPARATOR);
190
191        if (event.getContextStack() != null && !event.getContextStack().isEmpty()) {
192            sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
193            sbuf.append(";\" colspan=\"6\" ");
194            sbuf.append("title=\"Nested Diagnostic Context\">");
195            sbuf.append("NDC: ").append(Transform.escapeHtmlTags(event.getContextStack().toString()));
196            sbuf.append("</td></tr>").append(Strings.LINE_SEPARATOR);
197        }
198
199        if (event.getContextData() != null && !event.getContextData().isEmpty()) {
200            sbuf.append("<tr><td bgcolor=\"#EEEEEE\" style=\"font-size : ").append(fontSize);
201            sbuf.append(";\" colspan=\"6\" ");
202            sbuf.append("title=\"Mapped Diagnostic Context\">");
203            sbuf.append("MDC: ").append(Transform.escapeHtmlTags(event.getContextData().toMap().toString()));
204            sbuf.append("</td></tr>").append(Strings.LINE_SEPARATOR);
205        }
206
207        final Throwable throwable = event.getThrown();
208        if (throwable != null) {
209            sbuf.append("<tr><td bgcolor=\"#993300\" style=\"color:White; font-size : ").append(fontSize);
210            sbuf.append(";\" colspan=\"6\">");
211            appendThrowableAsHtml(throwable, sbuf);
212            sbuf.append("</td></tr>").append(Strings.LINE_SEPARATOR);
213        }
214
215        return sbuf.toString();
216    }
217
218    @Override
219    /**
220     * @return The content type.
221     */
222    public String getContentType() {
223        return contentType;
224    }
225
226    private void appendThrowableAsHtml(final Throwable throwable, final StringBuilder sbuf) {
227        final StringWriter sw = new StringWriter();
228        final PrintWriter pw = new PrintWriter(sw);
229        try {
230            throwable.printStackTrace(pw);
231        } catch (final RuntimeException ex) {
232            // Ignore the exception.
233        }
234        pw.flush();
235        final LineNumberReader reader = new LineNumberReader(new StringReader(sw.toString()));
236        final ArrayList<String> lines = new ArrayList<>();
237        try {
238          String line = reader.readLine();
239          while (line != null) {
240            lines.add(line);
241            line = reader.readLine();
242          }
243        } catch (final IOException ex) {
244            if (ex instanceof InterruptedIOException) {
245                Thread.currentThread().interrupt();
246            }
247            lines.add(ex.toString());
248        }
249        boolean first = true;
250        for (final String line : lines) {
251            if (!first) {
252                sbuf.append(TRACE_PREFIX);
253            } else {
254                first = false;
255            }
256            sbuf.append(Transform.escapeHtmlTags(line));
257            sbuf.append(Strings.LINE_SEPARATOR);
258        }
259    }
260
261    private StringBuilder appendLs(final StringBuilder sbuilder, final String s) {
262        sbuilder.append(s).append(Strings.LINE_SEPARATOR);
263        return sbuilder;
264    }
265
266    private StringBuilder append(final StringBuilder sbuilder, final String s) {
267        sbuilder.append(s);
268        return sbuilder;
269    }
270
271    /**
272     * Returns appropriate HTML headers.
273     * @return The header as a byte array.
274     */
275    @Override
276    public byte[] getHeader() {
277        final StringBuilder sbuf = new StringBuilder();
278        append(sbuf, "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\" ");
279        appendLs(sbuf, "\"http://www.w3.org/TR/html4/loose.dtd\">");
280        appendLs(sbuf, "<html>");
281        appendLs(sbuf, "<head>");
282        append(sbuf, "<meta charset=\"");
283        append(sbuf, getCharset().toString());
284        appendLs(sbuf, "\"/>");
285        append(sbuf, "<title>").append(title);
286        appendLs(sbuf, "</title>");
287        appendLs(sbuf, "<style type=\"text/css\">");
288        appendLs(sbuf, "<!--");
289        append(sbuf, "body, table {font-family:").append(font).append("; font-size: ");
290        appendLs(sbuf, headerSize).append(";}");
291        appendLs(sbuf, "th {background: #336699; color: #FFFFFF; text-align: left;}");
292        appendLs(sbuf, "-->");
293        appendLs(sbuf, "</style>");
294        appendLs(sbuf, "</head>");
295        appendLs(sbuf, "<body bgcolor=\"#FFFFFF\" topmargin=\"6\" leftmargin=\"6\">");
296        appendLs(sbuf, "<hr size=\"1\" noshade=\"noshade\">");
297        appendLs(sbuf, "Log session start time " + new java.util.Date() + "<br>");
298        appendLs(sbuf, "<br>");
299        appendLs(sbuf,
300                "<table cellspacing=\"0\" cellpadding=\"4\" border=\"1\" bordercolor=\"#224466\" width=\"100%\">");
301        appendLs(sbuf, "<tr>");
302        appendLs(sbuf, "<th>Time</th>");
303        appendLs(sbuf, "<th>Thread</th>");
304        appendLs(sbuf, "<th>Level</th>");
305        appendLs(sbuf, "<th>Logger</th>");
306        if (locationInfo) {
307            appendLs(sbuf, "<th>File:Line</th>");
308        }
309        appendLs(sbuf, "<th>Message</th>");
310        appendLs(sbuf, "</tr>");
311        return sbuf.toString().getBytes(getCharset());
312    }
313
314    /**
315     * Returns the appropriate HTML footers.
316     * @return the footer as a byte array.
317     */
318    @Override
319    public byte[] getFooter() {
320        final StringBuilder sbuf = new StringBuilder();
321        appendLs(sbuf, "</table>");
322        appendLs(sbuf, "<br>");
323        appendLs(sbuf, "</body></html>");
324        return getBytes(sbuf.toString());
325    }
326
327    /**
328     * Creates an HTML Layout.
329     * @param locationInfo If "true", location information will be included. The default is false.
330     * @param title The title to include in the file header. If none is specified the default title will be used.
331     * @param contentType The content type. Defaults to "text/html".
332     * @param charset The character set to use. If not specified, the default will be used.
333     * @param fontSize The font size of the text.
334     * @param font The font to use for the text.
335     * @return An HTML Layout.
336     */
337    @PluginFactory
338    public static HtmlLayout createLayout(
339            @PluginAttribute(value = "locationInfo") final boolean locationInfo,
340            @PluginAttribute(value = "title", defaultString = DEFAULT_TITLE) final String title,
341            @PluginAttribute("contentType") String contentType,
342            @PluginAttribute(value = "charset", defaultString = "UTF-8") final Charset charset,
343            @PluginAttribute("fontSize") String fontSize,
344            @PluginAttribute(value = "fontName", defaultString = DEFAULT_FONT_FAMILY) final String font) {
345        final FontSize fs = FontSize.getFontSize(fontSize);
346        fontSize = fs.getFontSize();
347        final String headerSize = fs.larger().getFontSize();
348        if (contentType == null) {
349            contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
350        }
351        return new HtmlLayout(locationInfo, title, contentType, charset, font, fontSize, headerSize);
352    }
353
354    /**
355     * Creates an HTML Layout using the default settings.
356     *
357     * @return an HTML Layout.
358     */
359    public static HtmlLayout createDefaultLayout() {
360        return newBuilder().build();
361    }
362
363    @PluginBuilderFactory
364    public static Builder newBuilder() {
365        return new Builder();
366    }
367
368    public static class Builder implements org.apache.logging.log4j.core.util.Builder<HtmlLayout> {
369
370        @PluginBuilderAttribute
371        private boolean locationInfo = false;
372
373        @PluginBuilderAttribute
374        private String title = DEFAULT_TITLE;
375
376        @PluginBuilderAttribute
377        private String contentType = null; // defer default value in order to use specified charset
378
379        @PluginBuilderAttribute
380        private Charset charset = StandardCharsets.UTF_8;
381
382        @PluginBuilderAttribute
383        private FontSize fontSize = FontSize.SMALL;
384
385        @PluginBuilderAttribute
386        private String fontName = DEFAULT_FONT_FAMILY;
387
388        private Builder() {
389        }
390
391        public Builder withLocationInfo(final boolean locationInfo) {
392            this.locationInfo = locationInfo;
393            return this;
394        }
395
396        public Builder withTitle(final String title) {
397            this.title = title;
398            return this;
399        }
400
401        public Builder withContentType(final String contentType) {
402            this.contentType = contentType;
403            return this;
404        }
405
406        public Builder withCharset(final Charset charset) {
407            this.charset = charset;
408            return this;
409        }
410
411        public Builder withFontSize(final FontSize fontSize) {
412            this.fontSize = fontSize;
413            return this;
414        }
415
416        public Builder withFontName(final String fontName) {
417            this.fontName = fontName;
418            return this;
419        }
420
421        @Override
422        public HtmlLayout build() {
423            // TODO: extract charset from content-type
424            if (contentType == null) {
425                contentType = DEFAULT_CONTENT_TYPE + "; charset=" + charset;
426            }
427            return new HtmlLayout(locationInfo, title, contentType, charset, fontName, fontSize.getFontSize(),
428                fontSize.larger().getFontSize());
429        }
430    }
431}