BIGTOP-622. Add test for HDFS Balancer (Sujay Rau via rvs)

git-svn-id: https://svn.apache.org/repos/asf/incubator/bigtop/trunk@1353342 13f79535-47bb-0310-9956-ffa450edef68

bigtop-tests/test-artifacts/hadoop/src/main/groovy/org/apache/bigtop/itest/hdfstests/TestHDFSBalancer.groovy

@@ -0,0 +1,84 @@
+/*
+ * 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.bigtop.itest.hdfstests;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.apache.bigtop.itest.JarContent;
+import org.apache.bigtop.itest.shell.Shell;
+
+public class TestHDFSBalancer {
+
+  private static Shell shHDFS = new Shell("/bin/bash", "hdfs");
+  // set with -Dthreshold
+  private static String thresh = "10";
+
+  @BeforeClass
+  public static void setUp() {
+    // unpack resource
+    JarContent.unpackJarContainer(TestHDFSBalancer.class, "." , null);
+    if (System.getProperty("threshold") != null) {
+      thresh = System.getProperty("threshold");
+    }  
+  }
+
+  @AfterClass
+  public static void tearDown() {
+  }
+
+  @Test
+  public void testBalancer() { 
+    System.out.println("Running Balancer:");
+    System.out.println("Threshold is set to " + thresh +". Toggle by adding -Dthreshold=#");
+
+    // must run balancer as hdfs user   
+    shHDFS.exec("hdfs balancer -threshold $thresh");
+
+    boolean success = false;
+    // success_string message signifies balancing worked correctly
+    String success_string1 = "The cluster is balanced. Exiting..."
+    String success_string2 = "No block can be moved"
+    String success_string3 = "No block has been moved for 3 iterations"
+    List out_msgs = shHDFS.getOut();
+    Iterator out_iter = out_msgs.iterator();
+    while (out_iter.hasNext()) {
+      String next_val = out_iter.next();
+      if (next_val.equals(success_string1) || next_val.contains(success_string2) || next_val.contains(success_string3)) {
+        success = true;
+       }
+    }
+
+    String failure_string1 = "namenodes = []"
+    List err_msgs = shHDFS.getErr();
+    Iterator err = err_msgs.iterator();
+
+    while (err.hasNext()) {
+      String err_next = err.next()
+      assertTrue("Balancer could not find namenode", !err_next.contains(failure_string1));
+    }
+
+    // could not just check if shHDFS.getRet() = 0 because balancer prints out INFO messages that the shell thinks are error messages 
+    assertTrue("Balancer failed", success == true);
+  }
+
+}
+