YARN-1706. Created an utility method to dump timeline records to JSON strings. Contributed by Zhijie Shen.

svn merge --ignore-ancestry -c 1566982 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1566983 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -144,6 +144,9 @@ Release 2.4.0 - UNRELEASED
     on the configuration-provider mechanism during startup too. (Xuan Gong via
     vinodkv)
 
+    YARN-1706. Created an utility method to dump timeline records to JSON
+    strings. (zjshen)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/TimelineUtils.java

@@ -0,0 +1,86 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.yarn.util;
+
+import java.io.IOException;
+
+import org.apache.hadoop.classification.InterfaceAudience.Public;
+import org.apache.hadoop.classification.InterfaceStability.Evolving;
+import org.codehaus.jackson.JsonGenerationException;
+import org.codehaus.jackson.map.AnnotationIntrospector;
+import org.codehaus.jackson.map.JsonMappingException;
+import org.codehaus.jackson.map.ObjectMapper;
+import org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion;
+import org.codehaus.jackson.xc.JaxbAnnotationIntrospector;
+
+/**
+ * The helper class for the timeline module.
+ * 
+ */
+@Public
+@Evolving
+public class TimelineUtils {
+
+  private static ObjectMapper mapper;
+
+  static {
+    mapper = new ObjectMapper();
+    AnnotationIntrospector introspector = new JaxbAnnotationIntrospector();
+    mapper.setAnnotationIntrospector(introspector);
+    mapper.getSerializationConfig()
+        .setSerializationInclusion(Inclusion.NON_NULL);
+  }
+
+  /**
+   * Serialize a POJO object into a JSON string not in a pretty format
+   * 
+   * @param o
+   *          an object to serialize
+   * @return a JSON string
+   * @throws IOException
+   * @throws JsonMappingException
+   * @throws JsonGenerationException
+   */
+  public static String dumpTimelineRecordtoJSON(Object o)
+      throws JsonGenerationException, JsonMappingException, IOException {
+    return dumpTimelineRecordtoJSON(o, false);
+  }
+
+  /**
+   * Serialize a POJO object into a JSON string
+   * 
+   * @param o
+   *          an object to serialize
+   * @param pretty
+   *          whether in a pretty format or not
+   * @return a JSON string
+   * @throws IOException
+   * @throws JsonMappingException
+   * @throws JsonGenerationException
+   */
+  public static String dumpTimelineRecordtoJSON(Object o, boolean pretty)
+      throws JsonGenerationException, JsonMappingException, IOException {
+    if (pretty) {
+      return mapper.defaultPrettyPrintingWriter().writeValueAsString(o);
+    } else {
+      return mapper.writeValueAsString(o);
+    }
+  }
+
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/api/records/apptimeline/TestApplicationTimelineRecords.java

@@ -19,18 +19,23 @@
 package org.apache.hadoop.yarn.api.records.apptimeline;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 import junit.framework.Assert;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.yarn.api.records.apptimeline.ATSPutErrors.ATSPutError;
+import org.apache.hadoop.yarn.util.TimelineUtils;
 import org.junit.Test;
 
 public class TestApplicationTimelineRecords {
 
+  private static final Log LOG =
+      LogFactory.getLog(TestApplicationTimelineRecords.class);
+
   @Test
-  public void testATSEntities() {
+  public void testATSEntities() throws Exception {
     ATSEntities entities = new ATSEntities();
     for (int j = 0; j < 2; ++j) {
       ATSEntity entity = new ATSEntity();
@@ -53,6 +58,9 @@ public class TestApplicationTimelineRecords {
       entity.addOtherInfo("okey2", "oval2");
       entities.addEntity(entity);
     }
+    LOG.info("Entities in JSON:");
+    LOG.info(TimelineUtils.dumpTimelineRecordtoJSON(entities, true));
+
     Assert.assertEquals(2, entities.getEntities().size());
     ATSEntity entity1 = entities.getEntities().get(0);
     Assert.assertEquals("entity id 0", entity1.getEntityId());
@@ -71,7 +79,7 @@ public class TestApplicationTimelineRecords {
   }
 
   @Test
-  public void testATSEvents() {
+  public void testATSEvents() throws Exception {
     ATSEvents events = new ATSEvents();
     for (int j = 0; j < 2; ++j) {
       ATSEvents.ATSEventsOfOneEntity partEvents =
@@ -88,6 +96,9 @@ public class TestApplicationTimelineRecords {
       }
       events.addEvent(partEvents);
     }
+    LOG.info("Events in JSON:");
+    LOG.info(TimelineUtils.dumpTimelineRecordtoJSON(events, true));
+
     Assert.assertEquals(2, events.getAllEvents().size());
     ATSEvents.ATSEventsOfOneEntity partEvents1 = events.getAllEvents().get(0);
     Assert.assertEquals("entity id 0", partEvents1.getEntityId());
@@ -112,7 +123,7 @@ public class TestApplicationTimelineRecords {
   }
 
   @Test
-  public void testATSPutErrors() {
+  public void testATSPutErrors() throws Exception {
     ATSPutErrors atsPutErrors = new ATSPutErrors();
     ATSPutError error1 = new ATSPutError();
     error1.setEntityId("entity id 1");
@@ -127,6 +138,8 @@ public class TestApplicationTimelineRecords {
     error2.setErrorCode(ATSPutError.IO_EXCEPTION);
     errors.add(error2);
     atsPutErrors.addErrors(errors);
+    LOG.info("Errors in JSON:");
+    LOG.info(TimelineUtils.dumpTimelineRecordtoJSON(atsPutErrors, true));
 
     Assert.assertEquals(3, atsPutErrors.getErrors().size());
     ATSPutError e = atsPutErrors.getErrors().get(0);