YARN-5922. Remove direct references of HBaseTimelineWriter/Reader in core ATS classes. Contributed by Haibo Chen.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-api/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java

@@ -2019,9 +2019,18 @@ public static boolean isAclEnabled(Configuration conf) {
   public static final String TIMELINE_SERVICE_WRITER_CLASS =
       TIMELINE_SERVICE_PREFIX + "writer.class";
 
+  public static final String DEFAULT_TIMELINE_SERVICE_WRITER_CLASS =
+      "org.apache.hadoop.yarn.server.timelineservice"
+          + ".storage.HBaseTimelineWriterImpl";
+
   public static final String TIMELINE_SERVICE_READER_CLASS =
       TIMELINE_SERVICE_PREFIX + "reader.class";
 
+  public static final String DEFAULT_TIMELINE_SERVICE_READER_CLASS =
+      "org.apache.hadoop.yarn.server.timelineservice" +
+          ".storage.HBaseTimelineReaderImpl";
+
+
   /** The setting that controls how often the timeline collector flushes the
    * timeline writer.
    */

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/collector/TimelineCollectorManager.java

@@ -36,7 +36,6 @@
 import org.apache.hadoop.yarn.api.records.ApplicationId;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
-import org.apache.hadoop.yarn.server.timelineservice.storage.HBaseTimelineWriterImpl;
 import org.apache.hadoop.yarn.server.timelineservice.storage.TimelineWriter;
 
 import com.google.common.annotations.VisibleForTesting;
@@ -59,10 +58,7 @@ public class TimelineCollectorManager extends AbstractService {
 
   @Override
   public void serviceInit(Configuration conf) throws Exception {
-    writer = ReflectionUtils.newInstance(conf.getClass(
+    writer = createTimelineWriter(conf);
-        YarnConfiguration.TIMELINE_SERVICE_WRITER_CLASS,
-        HBaseTimelineWriterImpl.class,
-        TimelineWriter.class), conf);
     writer.init(conf);
     // create a single dedicated thread for flushing the writer on a periodic
     // basis
@@ -75,6 +71,26 @@ public void serviceInit(Configuration conf) throws Exception {
     super.serviceInit(conf);
   }
 
+  private TimelineWriter createTimelineWriter(final Configuration conf) {
+    String timelineWriterClassName = conf.get(
+        YarnConfiguration.TIMELINE_SERVICE_WRITER_CLASS,
+            YarnConfiguration.DEFAULT_TIMELINE_SERVICE_WRITER_CLASS);
+    LOG.info("Using TimelineWriter: " + timelineWriterClassName);
+    try {
+      Class<?> timelineWriterClazz = Class.forName(timelineWriterClassName);
+      if (TimelineWriter.class.isAssignableFrom(timelineWriterClazz)) {
+        return (TimelineWriter) ReflectionUtils.newInstance(
+            timelineWriterClazz, conf);
+      } else {
+        throw new YarnRuntimeException("Class: " + timelineWriterClassName
+            + " not instance of " + TimelineWriter.class.getCanonicalName());
+      }
+    } catch (ClassNotFoundException e) {
+      throw new YarnRuntimeException("Could not instantiate TimelineWriter: "
+          + timelineWriterClassName, e);
+    }
+  }
+
   @Override
   protected void serviceStart() throws Exception {
     super.serviceStart();

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/reader/TimelineReaderServer.java

@@ -41,7 +41,6 @@
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
 import org.apache.hadoop.yarn.exceptions.YarnException;
 import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
-import org.apache.hadoop.yarn.server.timelineservice.storage.HBaseTimelineReaderImpl;
 import org.apache.hadoop.yarn.server.timelineservice.storage.TimelineReader;
 import org.apache.hadoop.yarn.webapp.GenericExceptionHandler;
 import org.apache.hadoop.yarn.webapp.YarnJacksonJaxbJsonProvider;
@@ -72,21 +71,34 @@ protected void serviceInit(Configuration conf) throws Exception {
     }
 
     TimelineReader timelineReaderStore = createTimelineReaderStore(conf);
+    timelineReaderStore.init(conf);
     addService(timelineReaderStore);
     timelineReaderManager = createTimelineReaderManager(timelineReaderStore);
     addService(timelineReaderManager);
     super.serviceInit(conf);
   }
 
-  private TimelineReader createTimelineReaderStore(Configuration conf) {
+  private TimelineReader createTimelineReaderStore(final Configuration conf) {
-    TimelineReader readerStore = ReflectionUtils.newInstance(conf.getClass(
+    String timelineReaderClassName = conf.get(
         YarnConfiguration.TIMELINE_SERVICE_READER_CLASS,
-        HBaseTimelineReaderImpl.class, TimelineReader.class), conf);
+        YarnConfiguration.DEFAULT_TIMELINE_SERVICE_READER_CLASS);
-    LOG.info("Using store " + readerStore.getClass().getName());
+    LOG.info("Using store: " + timelineReaderClassName);
-    readerStore.init(conf);
+    try {
-    return readerStore;
+      Class<?> timelineReaderClazz = Class.forName(timelineReaderClassName);
+      if (TimelineReader.class.isAssignableFrom(timelineReaderClazz)) {
+        return (TimelineReader) ReflectionUtils.newInstance(
+            timelineReaderClazz, conf);
+      } else {
+        throw new YarnRuntimeException("Class: " + timelineReaderClassName
+            + " not instance of " + TimelineReader.class.getCanonicalName());
+      }
+    } catch (ClassNotFoundException e) {
+      throw new YarnRuntimeException("Could not instantiate TimelineReader: "
+          + timelineReaderClassName, e);
+    }
   }
 
+
   private TimelineReaderManager createTimelineReaderManager(
       TimelineReader timelineReaderStore) {
     return new TimelineReaderManager(timelineReaderStore);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/collector/TestTimelineCollectorManager.java

@@ -0,0 +1,74 @@
+/**
+ * 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.server.timelineservice.collector;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
+import org.apache.hadoop.yarn.server.timelineservice.storage.FileSystemTimelineWriterImpl;
+import org.apache.hadoop.yarn.server.timelineservice.storage.TimelineWriter;
+import org.junit.Test;
+
+/**
+ * Unit tests for TimelineCollectorManager.
+ */
+public class TestTimelineCollectorManager{
+
+  @Test(timeout = 60000, expected = YarnRuntimeException.class)
+  public void testTimelineCollectorManagerWithInvalidTimelineWriter() {
+    Configuration conf = new YarnConfiguration();
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_WRITER_CLASS,
+        Object.class.getName());
+    runTimelineCollectorManagerWithConfig(conf);
+  }
+
+  @Test(timeout = 60000, expected = YarnRuntimeException.class)
+  public void testTimelineCollectorManagerWithNonexistentTimelineWriter() {
+    String nonexistentTimelineWriterClass = "org.apache.org.yarn.server." +
+        "timelineservice.storage.XXXXXXXX";
+    Configuration conf = new YarnConfiguration();
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_WRITER_CLASS,
+        nonexistentTimelineWriterClass);
+    runTimelineCollectorManagerWithConfig(conf);
+  }
+
+  @Test(timeout = 60000)
+  public void testTimelineCollectorManagerWithFileSystemWriter() {
+    Configuration conf = new YarnConfiguration();
+    conf.setClass(YarnConfiguration.TIMELINE_SERVICE_WRITER_CLASS,
+        FileSystemTimelineWriterImpl.class, TimelineWriter.class);
+    runTimelineCollectorManagerWithConfig(conf);
+  }
+
+  /**
+   * Run a TimelineCollectorManager with a given configuration.
+   * @param conf configuration to run TimelineCollectorManager with
+   */
+  private static void runTimelineCollectorManagerWithConfig(
+      final Configuration conf) {
+    TimelineCollectorManager collectorManager =
+        new TimelineCollectorManager("testTimelineCollectorManager");
+    try {
+      collectorManager.init(conf);
+      collectorManager.start();
+    } finally {
+      collectorManager.stop();
+    }
+  }
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/reader/TestTimelineReaderServer.java

@@ -23,6 +23,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.service.Service.STATE;
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.exceptions.YarnRuntimeException;
 import org.apache.hadoop.yarn.server.timelineservice.storage.FileSystemTimelineReaderImpl;
 import org.apache.hadoop.yarn.server.timelineservice.storage.TimelineReader;
 import org.junit.Test;
@@ -54,4 +55,46 @@ public void testStartStopServer() throws Exception {
       server.stop();
     }
   }
+
+  @Test(timeout = 60000, expected = YarnRuntimeException.class)
+  public void testTimelineReaderServerWithInvalidTimelineReader() {
+    Configuration conf = new YarnConfiguration();
+    conf.setBoolean(YarnConfiguration.TIMELINE_SERVICE_ENABLED, true);
+    conf.setFloat(YarnConfiguration.TIMELINE_SERVICE_VERSION, 2.0f);
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_WEBAPP_ADDRESS,
+        "localhost:0");
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_READER_CLASS,
+        Object.class.getName());
+    runTimelineReaderServerWithConfig(conf);
+  }
+
+  @Test(timeout = 60000, expected = YarnRuntimeException.class)
+  public void testTimelineReaderServerWithNonexistentTimelineReader() {
+    String nonexistentTimelineReaderClass = "org.apache.org.yarn.server." +
+        "timelineservice.storage.XXXXXXXX";
+    Configuration conf = new YarnConfiguration();
+    conf.setBoolean(YarnConfiguration.TIMELINE_SERVICE_ENABLED, true);
+    conf.setFloat(YarnConfiguration.TIMELINE_SERVICE_VERSION, 2.0f);
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_WEBAPP_ADDRESS,
+        "localhost:0");
+    conf.set(YarnConfiguration.TIMELINE_SERVICE_READER_CLASS,
+        nonexistentTimelineReaderClass);
+    runTimelineReaderServerWithConfig(conf);
+  }
+
+  /**
+   * Run a TimelineReaderServer with a given configuration.
+   * @param conf configuration to run TimelineReaderServer with
+   */
+  private static void runTimelineReaderServerWithConfig(
+      final Configuration conf) {
+    TimelineReaderServer server = new TimelineReaderServer();
+    try {
+      server.init(conf);
+      server.start();
+    } finally {
+      server.stop();
+    }
+  }
+
 }