HADOOP-8218. RPC.closeProxy shouldn't throw error when closing a mock. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1306160 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -184,6 +184,9 @@ Release 0.23.3 - UNRELEASED
     HADOOP-8202. RPC stopProxy() does not close the proxy correctly.
     (Hari Mankude via suresh)
 
+    HADOOP-8218. RPC.closeProxy shouldn't throw error when closing a mock
+    (todd)
+
   BREAKDOWN OF HADOOP-7454 SUBTASKS
 
     HADOOP-7455. HA: Introduce HA Service Protocol Interface. (suresh)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ha/HealthMonitor.java

@@ -17,7 +17,6 @@
  */
 package org.apache.hadoop.ha;
 
-import java.io.Closeable;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.LinkedList;
@@ -195,9 +194,7 @@ class HealthMonitor {
       } catch (Throwable t) {
         LOG.warn("Transport-level exception trying to monitor health of " +
             targetToMonitor + ": " + t.getLocalizedMessage());
-        if (proxy instanceof Closeable) {
         RPC.stopProxy(proxy);
-        }
         proxy = null;
         enterState(State.SERVICE_NOT_RESPONDING);
         Thread.sleep(sleepAfterDisconnectMillis);

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/RPC.java

@@ -604,6 +604,9 @@ public class RPC {
       LOG.error("RPC.stopProxy called on non proxy.", e);
     }
     
+    // If you see this error on a mock object in a unit test you're
+    // developing, make sure to use MockitoUtil.mockProtocol() to
+    // create your mock.
     throw new HadoopIllegalArgumentException(
         "Cannot close proxy - is not Closeable or "
             + "does not provide closeable invocation handler "

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ha/DummyHAService.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.ha;
 
+import java.io.Closeable;
 import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.util.ArrayList;
@@ -56,7 +57,40 @@ class DummyHAService extends HAServiceTarget {
   }
   
   private HAServiceProtocol makeMock() {
-    return Mockito.spy(new HAServiceProtocol() {
+    return Mockito.spy(new MockHAProtocolImpl());
+  }
+
+  @Override
+  public InetSocketAddress getAddress() {
+    return address;
+  }
+
+  @Override
+  public HAServiceProtocol getProxy(Configuration conf, int timeout)
+      throws IOException {
+    return proxy;
+  }
+  
+  @Override
+  public NodeFencer getFencer() {
+    return fencer;
+  }
+
+  @Override
+  public void checkFencingConfigured() throws BadFencingConfigurationException {
+  }
+  
+  @Override
+  public String toString() {
+    return "DummyHAService #" + index;
+  }
+
+  public static HAServiceTarget getInstance(int serial) {
+    return instances.get(serial - 1);
+  }
+  
+  private class MockHAProtocolImpl implements
+      HAServiceProtocol, Closeable {
     @Override
     public void monitorHealth() throws HealthCheckFailedException,
         AccessControlException, IOException {
@@ -99,35 +133,9 @@ class DummyHAService extends HAServiceTarget {
         throw new IOException("Connection refused (fake)");
       }
     }
-    });
-  }
     
     @Override
-  public InetSocketAddress getAddress() {
+    public void close() throws IOException {
-    return address;
     }
-
-  @Override
-  public HAServiceProtocol getProxy(Configuration conf, int timeout)
-      throws IOException {
-    return proxy;
-  }
-  
-  @Override
-  public NodeFencer getFencer() {
-    return fencer;
-  }
-
-  @Override
-  public void checkFencingConfigured() throws BadFencingConfigurationException {
-  }
-  
-  @Override
-  public String toString() {
-    return "DummyHAService #" + index;
-  }
-
-  public static HAServiceTarget getInstance(int serial) {
-    return instances.get(serial - 1);
   }
 }

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ha/TestFailoverController.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.ha;
 
+import java.io.Closeable;
 import java.io.IOException;
 import java.net.InetSocketAddress;
 
@@ -33,7 +34,6 @@ import org.apache.hadoop.security.AccessControlException;
 import org.junit.Test;
 import org.mockito.Mockito;
 import org.mockito.internal.stubbing.answers.ThrowsException;
-import org.mockito.stubbing.Answer;
 
 import static org.junit.Assert.*;
 
@@ -228,7 +228,10 @@ public class TestFailoverController {
     // Getting a proxy to a dead server will throw IOException on call,
     // not on creation of the proxy.
     HAServiceProtocol errorThrowingProxy = Mockito.mock(HAServiceProtocol.class,
-        new ThrowsException(new IOException("Could not connect to host")));
+        Mockito.withSettings()
+          .defaultAnswer(new ThrowsException(
+              new IOException("Could not connect to host")))
+          .extraInterfaces(Closeable.class));
     Mockito.doReturn(errorThrowingProxy).when(svc1).getProxy();
     DummyHAService svc2 = new DummyHAService(HAServiceState.STANDBY, svc2Addr);
     svc1.fencer = svc2.fencer = setupFencer(AlwaysSucceedFencer.class.getName());

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/ipc/TestRPC.java

@@ -50,6 +50,7 @@ import org.apache.hadoop.security.token.SecretManager;
 import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.UserGroupInformation;
+import org.apache.hadoop.test.MockitoUtil;
 import org.junit.Test;
 import static org.junit.Assert.*;
 
@@ -58,8 +59,6 @@ import com.google.protobuf.DescriptorProtos.EnumDescriptorProto;
 
 import static org.apache.hadoop.test.MetricsAsserts.*;
 
-import static org.mockito.Mockito.*;
-
 /** Unit tests for RPC. */
 @SuppressWarnings("deprecation")
 public class TestRPC {
@@ -587,10 +586,18 @@ public class TestRPC {
    */
   @Test(expected=HadoopIllegalArgumentException.class)
   public void testStopNonRegisteredProxy() throws Exception {
-    RPC.stopProxy(mock(TestProtocol.class));
     RPC.stopProxy(null);
   }
 
+  /**
+   * Test that the mockProtocol helper returns mock proxies that can
+   * be stopped without error.
+   */
+  @Test
+  public void testStopMockObject() throws Exception {
+    RPC.stopProxy(MockitoUtil.mockProtocol(TestProtocol.class)); 
+  }
+  
   @Test
   public void testStopProxy() throws IOException {
     StoppedProtocol proxy = (StoppedProtocol) RPC.getProxy(StoppedProtocol.class,

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/test/MockitoUtil.java

@@ -0,0 +1,36 @@
+/**
+ * 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.test;
+
+import java.io.Closeable;
+
+import org.mockito.Mockito;
+
+public abstract class MockitoUtil {
+
+  /**
+   * Return a mock object for an IPC protocol. This special
+   * method is necessary, since the IPC proxies have to implement
+   * Closeable in addition to their protocol interface.
+   * @param clazz the protocol class
+   */
+  public static <T> T mockProtocol(Class<T> clazz) {
+    return Mockito.mock(clazz,
+        Mockito.withSettings().extraInterfaces(Closeable.class));
+  }
+}