From b6f20c36c2f221f64ff4197903303236644c7be5 Mon Sep 17 00:00:00 2001
From: Konstantin V Shvachko <shv@apache.org>
Date: Tue, 16 Oct 2018 16:35:02 -0700
Subject: [PATCH] HDFS-13925. Unit Test for transitioning between different
 states. Contributed by Sherwood Zheng.

---
 .../server/namenode/ha/TestObserverNode.java  | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestObserverNode.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestObserverNode.java
index 28fd330be4..b18c5b8e1a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestObserverNode.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestObserverNode.java
@@ -20,6 +20,7 @@
 import static org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter.getServiceState;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyBoolean;
 import static org.mockito.Matchers.anyLong;
@@ -30,11 +31,13 @@
 import java.net.URI;
 import java.util.ArrayList;
 import java.util.List;
+
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileUtil;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.ha.HAServiceProtocol.HAServiceState;
+import org.apache.hadoop.ha.ServiceFailedException;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.protocol.Block;
@@ -99,6 +102,26 @@ public static void shutDownCluster() throws IOException {
     }
   }
 
+  @Test
+  public void testNoActiveToObserver() throws Exception {
+    try {
+      dfsCluster.transitionToObserver(0);
+    } catch (ServiceFailedException e) {
+      return;
+    }
+    fail("active cannot be transitioned to observer");
+  }
+
+  @Test
+  public void testNoObserverToActive() throws Exception {
+    try {
+      dfsCluster.transitionToActive(2);
+    } catch (ServiceFailedException e) {
+      return;
+    }
+    fail("observer cannot be transitioned to active");
+  }
+
   @Test
   public void testSimpleRead() throws Exception {
     Path testPath2 = new Path(testPath, "test2");