HADOOP-8711. IPC Server supports adding exceptions for which the message is printed and the stack trace is not printed to avoid chatter. Contributed by Brandon Li.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1375790 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -91,6 +91,10 @@ Trunk (unreleased changes)
     HADOOP-8624. ProtobufRpcEngine should log all RPCs if TRACE logging is
     enabled (todd)
 
+    HADOOP-8711. IPC Server supports adding exceptions for which
+    the message is printed and the stack trace is not printed to avoid chatter.
+    (Brandon Li via Suresh)
+
   BUG FIXES
 
     HADOOP-8177. MBeans shouldn't try to register when it fails to create MBeanName.

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

@@ -46,11 +46,13 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Random;
+import java.util.Set;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.LinkedBlockingQueue;
@@ -108,6 +110,42 @@
 public abstract class Server {
   private final boolean authorize;
   private boolean isSecurityEnabled;
+  private ExceptionsHandler exceptionsHandler = new ExceptionsHandler();
+  
+  public void addTerseExceptions(Class<?>... exceptionClass) {
+    exceptionsHandler.addTerseExceptions(exceptionClass);
+  }
+
+  /**
+   * ExceptionsHandler manages Exception groups for special handling
+   * e.g., terse exception group for concise logging messages
+   */
+  static class ExceptionsHandler {
+    private volatile Set<String> terseExceptions = new HashSet<String>();
+
+    /**
+     * Add exception class so server won't log its stack trace.
+     * Modifying the terseException through this method is thread safe.
+     *
+     * @param exceptionClass exception classes 
+     */
+    void addTerseExceptions(Class<?>... exceptionClass) {
+
+      // Make a copy of terseException for performing modification
+      final HashSet<String> newSet = new HashSet<String>(terseExceptions);
+
+      // Add all class names into the HashSet
+      for (Class<?> name : exceptionClass) {
+        newSet.add(name.toString());
+      }
+      // Replace terseException set
+      terseExceptions = Collections.unmodifiableSet(newSet);
+    }
+
+    boolean isTerse(Class<?> t) {
+      return terseExceptions.contains(t.toString());
+    }
+  }
   
   /**
    * The first four bytes of Hadoop RPC connections
@@ -1704,8 +1742,8 @@ public Writable run() throws Exception {
               // on the server side, as opposed to just a normal exceptional
               // result.
               LOG.warn(logMsg, e);
-            } else if (e instanceof StandbyException) {
-              // Don't log the whole stack trace of these exceptions.
+            } else if (exceptionsHandler.isTerse(e.getClass())) {
+             // Don't log the whole stack trace of these exceptions.
               // Way too noisy!
               LOG.info(logMsg);
             } else {
@@ -1844,6 +1882,8 @@ protected Server(String bindAddress, int port,
     if (isSecurityEnabled) {
       SaslRpcServer.init(conf);
     }
+    
+    this.exceptionsHandler.addTerseExceptions(StandbyException.class);
   }
 
   private void closeConnection(Connection connection) {

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

@@ -20,6 +20,7 @@
 
 import static org.junit.Assert.*;
 
+import java.io.IOException;
 import java.net.BindException;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
@@ -115,4 +116,16 @@ public void testBindError() throws Exception {
       socket.close();
     }
   }
+  
+  @Test
+  public void testExceptionsHandler() throws IOException {
+    Server.ExceptionsHandler handler = new Server.ExceptionsHandler();
+    handler.addTerseExceptions(IOException.class);
+    handler.addTerseExceptions(RpcServerException.class, IpcException.class);
+
+    assertTrue(handler.isTerse(IOException.class));
+    assertTrue(handler.isTerse(RpcServerException.class));
+    assertTrue(handler.isTerse(IpcException.class));
+    assertFalse(handler.isTerse(RpcClientException.class));
+  }
 }