HDFS-12054. FSNamesystem#addErasureCodingPolicies should call checkNameNodeSafeMode() to ensure Namenode is not in safemode. Contributed by lufei.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -7081,6 +7081,8 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       checkOperation(OperationCategory.WRITE);
       for (ErasureCodingPolicy policy : policies) {
         try {
+          checkOperation(OperationCategory.WRITE);
+          checkNameNodeSafeMode("Cannot add erasure coding policy");
           ErasureCodingPolicy newPolicy =
               FSDirErasureCodingOp.addErasureCodePolicy(this, policy);
           addECPolicyName = newPolicy.getName();

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

@@ -40,6 +40,7 @@ import org.apache.hadoop.fs.permission.AclEntry;
 import org.apache.hadoop.fs.permission.FsAction;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.MiniDFSCluster.DataNodeProperties;
+import org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy;
 import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockManagerTestUtil;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.StartupOption;
@@ -48,6 +49,7 @@ import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.hdfs.server.namenode.NameNodeAdapter;
 import org.apache.hadoop.hdfs.server.namenode.SafeModeException;
 import org.apache.hadoop.io.IOUtils;
+import org.apache.hadoop.io.erasurecode.ECSchema;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -466,6 +468,20 @@ public class TestSafeMode {
       // expected
     }
 
+    ECSchema toAddSchema = new ECSchema("testcodec", 3, 2);
+    ErasureCodingPolicy newPolicy =
+        new ErasureCodingPolicy(toAddSchema, 128 * 1024);
+    ErasureCodingPolicy[] policyArray =
+        new ErasureCodingPolicy[]{newPolicy};
+    try {
+      dfs.addErasureCodingPolicies(policyArray);
+      fail("AddErasureCodingPolicies should have failed.");
+    } catch (IOException ioe) {
+      GenericTestUtils.assertExceptionContains(
+          "Cannot add erasure coding policy", ioe);
+      // expected
+    }
+
     assertFalse("Could not leave SM",
         dfs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE));
   }