svn merge -c 1593475 merging from trunk to branch-2 to fix:HDFS-6313. WebHdfs may use the wrong NN when configured for multiple HA NNs. Contributed by Kihwal Lee.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1593476 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -249,6 +249,9 @@ Release 2.4.1 - UNRELEASED
     HDFS-6329. WebHdfs does not work if HA is enabled on NN but logical URI is
     not configured. (kihwal)
 
+    HDFS-6313. WebHdfs may use the wrong NN when configured for multiple HA NNs
+    (kihwal)
+
 Release 2.4.0 - 2014-04-07 
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -101,6 +101,7 @@ import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.util.Progressable;
 import org.mortbay.util.ajax.JSON;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Charsets;
 import com.google.common.collect.Lists;
 
@@ -1112,12 +1113,12 @@ public class WebHdfsFileSystem extends FileSystem
       Map<String, Map<String, InetSocketAddress>> addresses = DFSUtil
           .getHaNnWebHdfsAddresses(conf, scheme);
 
-      for (Map<String, InetSocketAddress> addrs : addresses.values()) {
+      // Extract the entry corresponding to the logical name.
+      Map<String, InetSocketAddress> addrs = addresses.get(uri.getHost());
       for (InetSocketAddress addr : addrs.values()) {
         ret.add(addr);
       }
     }
-    }
 
     InetSocketAddress[] r = new InetSocketAddress[ret.size()];
     return ret.toArray(r);
@@ -1128,4 +1129,9 @@ public class WebHdfsFileSystem extends FileSystem
     return tokenServiceName == null ? super.getCanonicalServiceName()
         : tokenServiceName.toString();
   }
+
+  @VisibleForTesting
+  InetSocketAddress[] getResolvedNNAddr() {
+    return nnAddrs;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/DFSTestUtil.java

@@ -148,16 +148,40 @@ public class DFSTestUtil {
    */
   public static Configuration newHAConfiguration(final String logicalName) {
     Configuration conf = new Configuration();
+    addHAConfiguration(conf, logicalName);
+    return conf;
+  }
+
+  /**
+   * Add a new HA configuration.
+   */
+  public static void addHAConfiguration(Configuration conf,
+      final String logicalName) {
+    String nsIds = conf.get(DFSConfigKeys.DFS_NAMESERVICES);
+    if (nsIds == null) {
       conf.set(DFSConfigKeys.DFS_NAMESERVICES, logicalName);
+    } else { // append the nsid
+      conf.set(DFSConfigKeys.DFS_NAMESERVICES, nsIds + "," + logicalName);
+    }
     conf.set(DFSUtil.addKeySuffixes(DFSConfigKeys.DFS_HA_NAMENODES_KEY_PREFIX,
             logicalName), "nn1,nn2");
     conf.set(DFSConfigKeys.DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX + "" +
             "." + logicalName,
             ConfiguredFailoverProxyProvider.class.getName());
     conf.setInt(DFSConfigKeys.DFS_REPLICATION_KEY, 1);
-    return conf;
   }
 
+  public static void setFakeHttpAddresses(Configuration conf,
+      final String logicalName) {
+    conf.set(DFSUtil.addKeySuffixes(
+        DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY,
+        logicalName, "nn1"), "127.0.0.1:12345");
+    conf.set(DFSUtil.addKeySuffixes(
+        DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY,
+        logicalName, "nn2"), "127.0.0.1:12346");
+  }
+
+
   /** class MyFile contains enough information to recreate the contents of
    * a single file.
    */

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/web/TestWebHDFSForHA.java

@@ -156,4 +156,30 @@ public class TestWebHDFSForHA {
       }
     }
   }
+
+  @Test
+  public void testMultipleNamespacesConfigured() throws Exception {
+    Configuration conf = DFSTestUtil.newHAConfiguration(LOGICAL_NAME);
+    MiniDFSCluster cluster = null;
+    WebHdfsFileSystem fs = null;
+
+    try {
+      cluster = new MiniDFSCluster.Builder(conf).nnTopology(topo)
+              .numDataNodes(1).build();
+
+      HATestUtil.setFailoverConfigurations(cluster, conf, LOGICAL_NAME);
+
+      cluster.waitActive();
+      DFSTestUtil.addHAConfiguration(conf, LOGICAL_NAME + "remote");
+      DFSTestUtil.setFakeHttpAddresses(conf, LOGICAL_NAME + "remote");
+
+      fs = (WebHdfsFileSystem)FileSystem.get(WEBHDFS_URI, conf);
+      Assert.assertEquals(2, fs.getResolvedNNAddr().length);
+    } finally {
+      IOUtils.cleanup(null, fs);
+      if (cluster != null) {
+        cluster.shutdown();
+      }
+    }
+  }
 }