HADOOP-7469 Add a standard handler for socket connection problems

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1177645 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -27,6 +27,9 @@ Trunk (unreleased changes)
 
     HADOOP-7693. Enhance AvroRpcEngine to support the new #addProtocol
     interface introduced in HADOOP-7524.  (cutting)
+    
+    HADOOP-7469  Add a standard handler for socket connection problems which
+                 improves diagnostics (Uma Maheswara Rao G  and stevel via stevel)
 
   BUGS
 

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

@@ -23,8 +23,6 @@ import java.net.Socket;
 import java.net.InetSocketAddress;
 import java.net.SocketTimeoutException;
 import java.net.UnknownHostException;
-import java.net.ConnectException;
-
 import java.io.IOException;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
@@ -235,8 +233,11 @@ public class Client {
       this.remoteId = remoteId;
       this.server = remoteId.getAddress();
       if (server.isUnresolved()) {
-        throw new UnknownHostException("unknown host: " + 
-                                       remoteId.getAddress().getHostName());
+        throw NetUtils.wrapException(remoteId.getAddress().getHostName(),
+            remoteId.getAddress().getPort(),
+            null,
+            0,
+            new UnknownHostException());
       }
       this.rpcTimeout = remoteId.getRpcTimeout();
       this.maxIdleTime = remoteId.getMaxIdleTime();
@@ -1084,7 +1085,12 @@ public class Client {
           call.error.fillInStackTrace();
           throw call.error;
         } else { // local exception
-          throw wrapException(remoteId.getAddress(), call.error);
+          InetSocketAddress address = remoteId.getAddress();
+          throw NetUtils.wrapException(address.getHostName(),
+                  address.getPort(),
+                  NetUtils.getHostname(),
+                  0,
+                  call.error);
         }
       } else {
         return call.value;
@@ -1093,37 +1099,6 @@ public class Client {
   }
 
   /**
-   * Take an IOException and the address we were trying to connect to
-   * and return an IOException with the input exception as the cause.
-   * The new exception provides the stack trace of the place where 
-   * the exception is thrown and some extra diagnostics information.
-   * If the exception is ConnectException or SocketTimeoutException, 
-   * return a new one of the same type; Otherwise return an IOException.
-   * 
-   * @param addr target address
-   * @param exception the relevant exception
-   * @return an exception to throw
-   */
-  private IOException wrapException(InetSocketAddress addr,
-                                         IOException exception) {
-    if (exception instanceof ConnectException) {
-      //connection refused; include the host:port in the error
-      return (ConnectException)new ConnectException(
-           "Call to " + addr + " failed on connection exception: " + exception)
-                    .initCause(exception);
-    } else if (exception instanceof SocketTimeoutException) {
-      return (SocketTimeoutException)new SocketTimeoutException(
-           "Call to " + addr + " failed on socket timeout exception: "
-                      + exception).initCause(exception);
-    } else {
-      return (IOException)new IOException(
-           "Call to " + addr + " failed on local exception: " + exception)
-                                 .initCause(exception);
-
-    }
-  }
-
-  /** 
    * @deprecated Use {@link #call(Writable[], InetSocketAddress[], 
    * Class, UserGroupInformation, Configuration)} instead 
    */

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

@@ -51,8 +51,6 @@ import java.util.Random;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.LinkedBlockingQueue;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 
 import javax.security.sasl.Sasl;
 import javax.security.sasl.SaslException;
@@ -70,6 +68,7 @@ import org.apache.hadoop.io.WritableUtils;
 import org.apache.hadoop.ipc.RPC.VersionMismatch;
 import org.apache.hadoop.ipc.metrics.RpcDetailedMetrics;
 import org.apache.hadoop.ipc.metrics.RpcMetrics;
+import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.SaslRpcServer;
 import org.apache.hadoop.security.SaslRpcServer.AuthMethod;
@@ -227,20 +226,11 @@ public abstract class Server {
                           int backlog) throws IOException {
     try {
       socket.bind(address, backlog);
-    } catch (BindException e) {
-      BindException bindException = new BindException("Problem binding to " + address
-                                                      + " : " + e.getMessage());
-      bindException.initCause(e);
-      throw bindException;
     } catch (SocketException e) {
-      // If they try to bind to a different host's address, give a better
-      // error message.
-      if ("Unresolved address".equals(e.getMessage())) {
-        throw new UnknownHostException("Invalid hostname for server: " + 
-                                       address.getHostName());
-      } else {
-        throw e;
-      }
+      throw NetUtils.wrapException(null,
+          0,
+          address.getHostName(),
+          address.getPort(), e);
     }
   }
   

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/net/NetUtils.java

@@ -20,12 +20,15 @@ package org.apache.hadoop.net;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.net.BindException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.NetworkInterface;
+import java.net.NoRouteToHostException;
 import java.net.Socket;
 import java.net.SocketAddress;
 import java.net.SocketException;
+import java.net.SocketTimeoutException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.UnknownHostException;
@@ -54,6 +57,13 @@ public class NetUtils {
   
   private static Map<String, String> hostToResolved = 
                                      new HashMap<String, String>();
+  /** text to point users elsewhere: {@value} */
+  private static final String FOR_MORE_DETAILS_SEE
+      = " For more details see:  ";
+  /** text included in wrapped exceptions if the host is null: {@value} */
+  public static final String UNKNOWN_HOST = "(unknown)";
+  /** Base URL of the Hadoop Wiki: {@value} */
+  public static final String HADOOP_WIKI = "http://wiki.apache.org/hadoop/";
 
   /**
    * Get the socket factory for the given class according to its
@@ -537,4 +547,119 @@ public class NetUtils {
     }
     return local;
   }
+
+  /**
+   * Take an IOException , the local host port and remote host port details and
+   * return an IOException with the input exception as the cause and also
+   * include the host details. The new exception provides the stack trace of the
+   * place where the exception is thrown and some extra diagnostics information.
+   * If the exception is BindException or ConnectException or
+   * UnknownHostException or SocketTimeoutException, return a new one of the
+   * same type; Otherwise return an IOException.
+   *
+   * @param destHost target host (nullable)
+   * @param destPort target port
+   * @param localHost local host (nullable)
+   * @param localPort local port
+   * @param exception the caught exception.
+   * @return an exception to throw
+   */
+  public static IOException wrapException(final String destHost,
+                                          final int destPort,
+                                          final String localHost,
+                                          final int localPort,
+                                          final IOException exception) {
+    if (exception instanceof BindException) {
+      return new BindException(
+          "Problem binding to ["
+              + localHost
+              + ":"
+              + localPort
+              + "] "
+              + exception
+              + ";"
+              + see("BindException"));
+    } else if (exception instanceof ConnectException) {
+      // connection refused; include the host:port in the error
+      return (ConnectException) new ConnectException(
+          "Call From "
+              + localHost
+              + " to "
+              + destHost
+              + ":"
+              + destPort
+              + " failed on connection exception: "
+              + exception
+              + ";"
+              + see("ConnectionRefused"))
+          .initCause(exception);
+    } else if (exception instanceof UnknownHostException) {
+      return (UnknownHostException) new UnknownHostException(
+          "Invalid host name: "
+              + getHostDetailsAsString(destHost, destPort, localHost)
+              + exception
+              + ";"
+              + see("UnknownHost"))
+          .initCause(exception);
+    } else if (exception instanceof SocketTimeoutException) {
+      return (SocketTimeoutException) new SocketTimeoutException(
+          "Call From "
+              + localHost + " to " + destHost + ":" + destPort
+              + " failed on socket timeout exception: " + exception
+              + ";"
+              + see("SocketTimeout"))
+          .initCause(exception);
+    } else if (exception instanceof NoRouteToHostException) {
+      return (NoRouteToHostException) new NoRouteToHostException(
+          "No Route to Host from  "
+              + localHost + " to " + destHost + ":" + destPort
+              + " failed on socket timeout exception: " + exception
+              + ";"
+              + see("NoRouteToHost"))
+          .initCause(exception);
+    }
+    else {
+      return (IOException) new IOException("Failed on local exception: "
+                                               + exception
+                                               + "; Host Details : "
+                                               + getHostDetailsAsString(destHost, destPort, localHost))
+          .initCause(exception);
+
+    }
+  }
+
+  private static String see(final String entry) {
+    return FOR_MORE_DETAILS_SEE + HADOOP_WIKI + entry;
+  }
+
+  /**
+   * Get the host details as a string
+   * @param destHost destinatioon host (nullable)
+   * @param destPort destination port
+   * @param localHost local host (nullable)
+   * @return a string describing the destination host:port and the local host
+   */
+  private static String getHostDetailsAsString(final String destHost,
+                                               final int destPort,
+                                               final String localHost) {
+    StringBuilder hostDetails = new StringBuilder(27);
+    hostDetails.append("local host is: ")
+        .append(quoteHost(localHost))
+        .append("; ");
+    hostDetails.append("destination host is: \"").append(quoteHost(destHost))
+        .append(":")
+        .append(destPort).append("; ");
+    return hostDetails.toString();
+  }
+
+  /**
+   * Quote a hostname if it is not null
+   * @param hostname the hostname; nullable
+   * @return a quoted hostname or {@link #UNKNOWN_HOST} if the hostname is null
+   */
+  private static String quoteHost(final String hostname) {
+    return (hostname != null) ?
+        ("\"" + hostname + "\"")
+        : UNKNOWN_HOST;
+  }
 }

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

@@ -23,7 +23,6 @@ import org.apache.commons.logging.*;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.Writable;
 import org.apache.hadoop.io.LongWritable;
-import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.hadoop.net.NetUtils;
 
@@ -270,7 +269,7 @@ public class TestIPC {
       fail("Expected an exception to have been thrown");
     } catch (IOException e) {
       String message = e.getMessage();
-      String addressText = address.toString();
+      String addressText = address.getHostName() + ":" + address.getPort();
       assertTrue("Did not find "+addressText+" in "+message,
               message.contains(addressText));
       Throwable cause=e.getCause();

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/net/TestNetUtils.java

@@ -17,10 +17,15 @@
  */
 package org.apache.hadoop.net;
 
+import junit.framework.AssertionFailedError;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.junit.Test;
 
 import static org.junit.Assert.*;
 
+import java.io.IOException;
+import java.net.BindException;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.net.Socket;
@@ -34,6 +39,12 @@ import org.apache.hadoop.conf.Configuration;
 
 public class TestNetUtils {
 
+  private static final Log LOG = LogFactory.getLog(TestNetUtils.class);
+  private static final int DEST_PORT = 4040;
+  private static final String DEST_PORT_NAME = Integer.toString(DEST_PORT);
+  private static final int LOCAL_PORT = 8080;
+  private static final String LOCAL_PORT_NAME = Integer.toString(LOCAL_PORT);
+
   /**
    * Test that we can't accidentally connect back to the connecting socket due
    * to a quirk in the TCP spec.
@@ -120,4 +131,100 @@ public class TestNetUtils {
     }
     assertFalse(NetUtils.isLocalAddress(InetAddress.getByName("8.8.8.8")));
   }
+
+  @Test
+  public void testWrapConnectException() throws Throwable {
+    IOException e = new ConnectException("failed");
+    IOException wrapped = verifyExceptionClass(e, ConnectException.class);
+    assertInException(wrapped, "failed");
+    assertWikified(wrapped);
+    assertInException(wrapped, "localhost");
+    assertRemoteDetailsIncluded(wrapped);
+    assertInException(wrapped, "/ConnectionRefused");
+  }
+
+  @Test
+  public void testWrapBindException() throws Throwable {
+    IOException e = new BindException("failed");
+    IOException wrapped = verifyExceptionClass(e, BindException.class);
+    assertInException(wrapped, "failed");
+    assertLocalDetailsIncluded(wrapped);
+    assertNotInException(wrapped, DEST_PORT_NAME);
+    assertInException(wrapped, "/BindException");
+  }
+
+  @Test
+  public void testWrapUnknownHostException() throws Throwable {
+    IOException e = new UnknownHostException("failed");
+    IOException wrapped = verifyExceptionClass(e, UnknownHostException.class);
+    assertInException(wrapped, "failed");
+    assertWikified(wrapped);
+    assertInException(wrapped, "localhost");
+    assertRemoteDetailsIncluded(wrapped);
+    assertInException(wrapped, "/UnknownHost");
+  }
+
+  private void assertRemoteDetailsIncluded(IOException wrapped)
+      throws Throwable {
+    assertInException(wrapped, "desthost");
+    assertInException(wrapped, DEST_PORT_NAME);
+  }
+
+  private void assertLocalDetailsIncluded(IOException wrapped)
+      throws Throwable {
+    assertInException(wrapped, "localhost");
+    assertInException(wrapped, LOCAL_PORT_NAME);
+  }
+
+  private void assertWikified(Exception e) throws Throwable {
+    assertInException(e, NetUtils.HADOOP_WIKI);
+  }
+
+  private void assertInException(Exception e, String text) throws Throwable {
+    String message = extractExceptionMessage(e);
+    if (!(message.contains(text))) {
+      throw new AssertionFailedError("Wrong text in message "
+                                         + "\"" + message + "\""
+                                         + " expected \"" + text + "\"")
+          .initCause(e);
+    }
+  }
+
+  private String extractExceptionMessage(Exception e) throws Throwable {
+    assertNotNull("Null Exception", e);
+    String message = e.getMessage();
+    if (message == null) {
+      throw new AssertionFailedError("Empty text in exception " + e)
+          .initCause(e);
+    }
+    return message;
+  }
+
+  private void assertNotInException(Exception e, String text)
+      throws Throwable{
+    String message = extractExceptionMessage(e);
+    if (message.contains(text)) {
+      throw new AssertionFailedError("Wrong text in message "
+                                         + "\"" + message + "\""
+                                         + " did not expect \"" + text + "\"")
+          .initCause(e);
+    }
+  }
+
+  private IOException verifyExceptionClass(IOException e,
+                                           Class expectedClass)
+      throws Throwable {
+    assertNotNull("Null Exception", e);
+    IOException wrapped =
+        NetUtils.wrapException("desthost", DEST_PORT,
+                               "localhost", LOCAL_PORT,
+                               e);
+    LOG.info(wrapped.toString(), wrapped);
+    if(!(wrapped.getClass().equals(expectedClass))) {
+      throw new AssertionFailedError("Wrong exception class; expected "
+                                         + expectedClass
+                                         + " got " + wrapped.getClass() + ": " + wrapped).initCause(wrapped);
+    }
+    return wrapped;
+  }
 }