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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.flume.appender;
18  
19  import org.apache.flume.event.SimpleEvent;
20  import org.apache.logging.log4j.Level;
21  import org.apache.logging.log4j.LoggingException;
22  import org.apache.logging.log4j.Marker;
23  import org.apache.logging.log4j.ThreadContext;
24  import org.apache.logging.log4j.core.LogEvent;
25  import org.apache.logging.log4j.core.helpers.UUIDUtil;
26  import org.apache.logging.log4j.message.MapMessage;
27  import org.apache.logging.log4j.message.Message;
28  import org.apache.logging.log4j.message.StructuredDataId;
29  import org.apache.logging.log4j.message.StructuredDataMessage;
30  
31  import java.io.ByteArrayOutputStream;
32  import java.io.IOException;
33  import java.util.ArrayList;
34  import java.util.HashMap;
35  import java.util.List;
36  import java.util.Map;
37  import java.util.zip.GZIPOutputStream;
38  
39  /**
40   * Class that is both a Flume and Log4j Event.
41   */
42  public class FlumeEvent extends SimpleEvent implements LogEvent {
43  
44      /**
45       * Generated serial version ID.
46       */
47      private static final long serialVersionUID = -8988674608627854140L;
48  
49      private static final String DEFAULT_MDC_PREFIX = "mdc:";
50  
51      private static final String DEFAULT_EVENT_PREFIX = "";
52  
53      private static final String EVENT_TYPE = "eventType";
54  
55      private static final String EVENT_ID = "eventId";
56  
57      private static final String GUID = "guId";
58  
59      private static final String TIMESTAMP = "timeStamp";;
60  
61      private final LogEvent event;
62  
63      private final Map<String, String> ctx = new HashMap<String, String>();
64  
65      private final boolean compress;
66  
67      /**
68       * Construct the FlumeEvent.
69       * @param event The Log4j LogEvent.
70       * @param includes A comma separated list of MDC elements to include.
71       * @param excludes A comma separated list of MDC elements to exclude.
72       * @param required A comma separated list of MDC elements that are required to be defined.
73       * @param mdcPrefix The value to prefix to MDC keys.
74       * @param eventPrefix The value to prefix to event keys.
75       * @param compress If true the event body should be compressed.
76       */
77      public FlumeEvent(final LogEvent event, final String includes, final String excludes, final String required,
78                        String mdcPrefix, String eventPrefix, final boolean compress) {
79          this.event = event;
80          this.compress = compress;
81          final Map<String, String> headers = getHeaders();
82          headers.put(TIMESTAMP, Long.toString(event.getMillis()));
83          if (mdcPrefix == null) {
84              mdcPrefix = DEFAULT_MDC_PREFIX;
85          }
86          if (eventPrefix == null) {
87              eventPrefix = DEFAULT_EVENT_PREFIX;
88          }
89          final Map<String, String> mdc = event.getContextMap();
90          if (includes != null) {
91              final String[] array = includes.split(",");
92              if (array.length > 0) {
93                  for (String str : array) {
94                      str = str.trim();
95                      if (mdc.containsKey(str)) {
96                          ctx.put(str, mdc.get(str));
97                      }
98                  }
99              }
100         } else if (excludes != null) {
101             final String[] array = excludes.split(",");
102             if (array.length > 0) {
103                 final List<String> list = new ArrayList<String>(array.length);
104                 for (final String value : array) {
105                     list.add(value.trim());
106                 }
107                 for (final Map.Entry<String, String> entry : mdc.entrySet()) {
108                     if (!list.contains(entry.getKey())) {
109                         ctx.put(entry.getKey(), entry.getValue());
110                     }
111                 }
112             }
113         } else {
114             ctx.putAll(mdc);
115         }
116 
117         if (required != null) {
118             final String[] array = required.split(",");
119             if (array.length > 0) {
120                 for (String str : array) {
121                     str = str.trim();
122                     if (!mdc.containsKey(str)) {
123                         throw new LoggingException("Required key " + str + " is missing from the MDC");
124                     }
125                 }
126             }
127         }
128         final Message message = event.getMessage();
129         if (message instanceof MapMessage) {
130             if (message instanceof StructuredDataMessage) {
131                 addStructuredData(eventPrefix, headers, (StructuredDataMessage) message);
132             }
133             addMapData(eventPrefix, headers, (MapMessage) message);
134         }
135 
136         addContextData(mdcPrefix, headers, ctx);
137 
138         addGuid(headers);
139     }
140 
141     protected void addStructuredData(final String prefix, final Map<String, String> fields,
142                                      final StructuredDataMessage msg) {
143         fields.put(prefix + EVENT_TYPE, msg.getType());
144         final StructuredDataId id = msg.getId();
145         fields.put(prefix + EVENT_ID, id.getName());
146     }
147 
148     protected void addMapData(final String prefix, final Map<String, String> fields, final MapMessage msg) {
149         final Map<String, String> data = msg.getData();
150         for (final Map.Entry<String, String> entry : data.entrySet()) {
151             fields.put(prefix + entry.getKey(), entry.getValue());
152         }
153     }
154 
155     protected void addContextData(final String prefix, final Map<String, String> fields,
156                                   final Map<String, String> context) {
157         for (final Map.Entry<String, String> entry : context.entrySet()) {
158             if (entry.getKey() != null && entry.getValue() != null) {
159                 fields.put(prefix + entry.getKey(), entry.getValue());
160             }
161         }
162     }
163 
164     protected void addGuid(final Map<String, String> fields) {
165         fields.put(GUID, UUIDUtil.getTimeBasedUUID().toString());
166     }
167 
168     /**
169      * Set the body in the event.
170      * @param body The body to add to the event.
171      */
172     @Override
173     public void setBody(final byte[] body) {
174         if (body == null || body.length == 0) {
175             super.setBody(new byte[0]);
176             return;
177         }
178         if (compress) {
179             final ByteArrayOutputStream baos = new ByteArrayOutputStream();
180             try {
181                 final GZIPOutputStream os = new GZIPOutputStream(baos);
182                 os.write(body);
183                 os.close();
184             } catch (final IOException ioe) {
185                 throw new LoggingException("Unable to compress message", ioe);
186             }
187             super.setBody(baos.toByteArray());
188         } else {
189             super.setBody(body);
190         }
191     }
192 
193     /**
194      * Get the Frequently Qualified Class Name.
195      * @return the FQCN String.
196      */
197     public String getFQCN() {
198         return event.getFQCN();
199     }
200 
201     /**
202      * Returns the logging Level.
203      * @return the Level.
204      */
205     public Level getLevel() {
206         return event.getLevel();
207     }
208 
209     /**
210      * Returns the logger name.
211      * @return the logger name.
212      */
213     public String getLoggerName() {
214         return event.getLoggerName();
215     }
216 
217     /**
218      * Returns the StackTraceElement for the caller of the logging API.
219      * @return the StackTraceElement of the caller.
220      */
221     public StackTraceElement getSource() {
222         return event.getSource();
223     }
224 
225     /**
226      * Returns the Message.
227      * @return the Message.
228      */
229     public Message getMessage() {
230         return event.getMessage();
231     }
232 
233     /**
234      * Returns the Marker.
235      * @return the Marker.
236      */
237     public Marker getMarker() {
238         return event.getMarker();
239     }
240 
241     /**
242      * Returns the name of the Thread.
243      * @return the name of the Thread.
244      */
245     public String getThreadName() {
246         return event.getThreadName();
247     }
248 
249     /**
250      * Returns the event timestamp.
251      * @return the event timestamp.
252      */
253     public long getMillis() {
254         return event.getMillis();
255     }
256 
257     /**
258      * Returns the Throwable associated with the event, if any.
259      * @return the Throwable.
260      */
261     public Throwable getThrown() {
262         return event.getThrown();
263     }
264 
265     /**
266      * Returns a copy of the context Map.
267      * @return a copy of the context Map.
268      */
269     public Map<String, String> getContextMap() {
270         return ctx;
271     }
272 
273     /**
274      * Returns a copy of the context stack.
275      * @return a copy of the context stack.
276      */
277     public ThreadContext.ContextStack getContextStack() {
278         return event.getContextStack();
279     }
280 }