diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java index dcce2aa5795..3a2f9825d82 100644 --- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java +++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Cluster.java @@ -24,8 +24,10 @@ import java.net.InetSocketAddress; import java.security.PrivilegedExceptionAction; import java.util.ArrayList; import java.util.List; +import java.util.ServiceConfigurationError; import java.util.ServiceLoader; +import com.google.common.annotations.VisibleForTesting; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.classification.InterfaceAudience; @@ -53,7 +55,7 @@ public class Cluster { @InterfaceStability.Evolving public static enum JobTrackerStatus {INITIALIZING, RUNNING}; - + private ClientProtocolProvider clientProtocolProvider; private ClientProtocol client; private UserGroupInformation ugi; @@ -64,7 +66,8 @@ public class Cluster { private Path jobHistoryDir = null; private static final Log LOG = LogFactory.getLog(Cluster.class); - private static ServiceLoader frameworkLoader = + @VisibleForTesting + static Iterable frameworkLoader = ServiceLoader.load(ClientProtocolProvider.class); private volatile List providerList = null; @@ -74,8 +77,15 @@ public class Cluster { if (providerList == null) { List localProviderList = new ArrayList(); - for (ClientProtocolProvider provider : frameworkLoader) { - localProviderList.add(provider); + try { + for (ClientProtocolProvider provider : frameworkLoader) { + localProviderList.add(provider); + } + } catch(ServiceConfigurationError e) { + LOG.info("Failed to instantiate ClientProtocolProvider, please " + + "check the /META-INF/services/org.apache." + + "hadoop.mapreduce.protocol.ClientProtocolProvider " + + "files on the classpath", e); } providerList = localProviderList; } diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapreduce/TestCluster.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapreduce/TestCluster.java new file mode 100644 index 00000000000..3aa0ff130b0 --- /dev/null +++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/test/java/org/apache/hadoop/mapreduce/TestCluster.java @@ -0,0 +1,81 @@ +/** + * 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.mapreduce; + +import org.apache.hadoop.conf.Configuration; + +import static org.mockito.Mockito.mock; +import static org.mockito.Mockito.when; +import static org.mockito.Mockito.verify; +import static org.mockito.Mockito.times; +import static org.junit.Assert.assertNotNull; + +import org.apache.hadoop.mapreduce.protocol.ClientProtocol; +import org.apache.hadoop.mapreduce.protocol.ClientProtocolProvider; +import org.junit.Test; + +import java.io.IOException; +import java.net.InetSocketAddress; +import java.util.Iterator; +import java.util.ServiceConfigurationError; + +/** + * Testing the Cluster initialization. + */ +public class TestCluster { + @Test + @SuppressWarnings("unchecked") + public void testProtocolProviderCreation() throws Exception { + Iterator iterator = mock(Iterator.class); + when(iterator.hasNext()).thenReturn(true, true, true, true); + when(iterator.next()).thenReturn(getClientProtocolProvider()) + .thenThrow(new ServiceConfigurationError("Test error")) + .thenReturn(getClientProtocolProvider()); + + Iterable frameworkLoader = mock(Iterable.class); + when(frameworkLoader.iterator()).thenReturn(iterator); + + Cluster.frameworkLoader = frameworkLoader; + Cluster testCluster = new Cluster(new Configuration()); + + // Check that we get the acceptable client, even after + // failure in instantiation. + assertNotNull("ClientProtocol is expected", testCluster.getClient()); + // Check if we do not try to load the providers after a failure. + verify(iterator, times(2)).next(); + } + + public ClientProtocolProvider getClientProtocolProvider() { + return new ClientProtocolProvider() { + @Override + public ClientProtocol create(Configuration conf) throws IOException { + return mock(ClientProtocol.class); + } + + @Override + public ClientProtocol create(InetSocketAddress addr, Configuration + conf) throws IOException { + return mock(ClientProtocol.class); + } + + @Override + public void close(ClientProtocol clientProtocol) throws IOException { + } + }; + } +}