Ctest created HDFS-15128:
----------------------------

             Summary: Unit test failing to clean testing data and caused Maven 
to crash
                 Key: HDFS-15128
                 URL: https://issues.apache.org/jira/browse/HDFS-15128
             Project: Hadoop HDFS
          Issue Type: Bug
          Components: hdfs, test
    Affects Versions: 3.2.1
            Reporter: Ctest


*Description:*

Actively-used test helper function `testVolumeConfig` in 
`org.apache.hadoop.hdfs.server.datanode.TestDataNodeVolumeFailureToleration` 
chmod a directory with invalid perm 000 for testing purposes but later failed 
to chmod back this directory with a valid perm if the assertion inside this 
function failed. Any subsequent `mvn test` command would fail to run if this 
test had failed before. It is because Maven failed to build itself as it did 
not have permission to clean the temporarily-generated directory that has perm 
000. See below for the code snippet that is buggy.

 

 
{code:java}
try {
      for (int i = 0; i < volumesFailed; i++) {
        prepareDirToFail(dirs[i]); // this will chmod dirs[i] to perm 000
      }
      restartDatanodes(volumesTolerated, manageDfsDirs);
    } catch (DiskErrorException e) {
     ...
    } finally {
...
    }
 
      assertEquals(expectedBPServiceState, bpServiceState);
 
      for (File dir : dirs) {
        FileUtil.chmod(dir.toString(), "755");
      }
    }
{code}
 

 

The failure of the statement `assertEquals(expectedBPServiceState, 
bpServiceState)` caused function to terminate without executing 
`FileUtil.chmod(dir.toString(), "755")` for each temporary directory with 
invalid perm 000 the test has created. 

 

*Consequence:*

Any subsequent `mvn test` command would fail to run if this test had failed 
before. It is because Maven failed to build itself since it does not have 
permission to clean this temporarily-generated directory. For details of the 
failure, see below:

 
{noformat}
[INFO] --- maven-antrun-plugin:1.7:run (create-log-dir) @ hadoop-hdfs ---
[INFO] Executing tasks
 
main:
[delete] Deleting directory 
/home/ctest/app/Ctest-Hadoop/hadoop-hdfs-project/hadoop-hdfs/target/test/data
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  8.349 s
[INFO] Finished at: 2019-12-27T03:53:04-06:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute 
goalorg.apache.maven.plugins:maven-antrun-plugin:1.7:run (create-log-dir) on 
project hadoop-hdfs: An Ant BuildException has occured: Unable to delete 
directory 
/home/ctest/app/Ctest-Hadoop/hadoop-hdfs-project/hadoop-hdfs/target/test/data/dfs/data/data1/current
[ERROR] around Ant part ...<delete 
dir="/home/ctest/app/Ctest-Hadoop/hadoop-hdfs-project/hadoop-hdfs/target/test/data"/>...
 @ 4:105 in 
/home/ctest/app/Ctest-Hadoop/hadoop-hdfs-project/hadoop-hdfs/target/antrun/build-main.xml
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e 
switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please 
read the following articles:
[ERROR] [Help 1] 
http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException{noformat}
 

 

 

*Root Cause:*

The test helper function 
`org.apache.hadoop.hdfs.server.datanode.TestDataNodeVolumeFailureToleration#testVolumeConfig`
 purposely set the directory 
`/home/ctest/app/Ctest-Hadoop/hadoop-hdfs-project/hadoop-hdfs/target/test/data/dfs/data/data1/current`
 to have perm 000. And at the end of this function, it changed the perm of this 
directory to 755. However, there is an assertion in this function before the 
perm was able to changed to 755. Once this assertion fails, the function 
terminates before the directory’s perm can be changed to 755. Hence, this 
directory was later unable to be removed by Maven for when executing `mvn 
test`. 

 

*Fix:*

In 
`org.apache.hadoop.hdfs.server.datanode.TestDataNodeVolumeFailureToleration#testVolumeConfig`,
 move the assertion `assertEquals(expectedBPServiceState, bpServiceState)`  to 
the last line of this function. This fix will fix the bug and will not change 
the test outcome. 

 

*Content for the patch:*
{code:java}
diff --git 
a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
 
b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
index a9e4096df4b..a492fa5fd44 100644
--- 
a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
+++ 
b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
@@ -256,11 +256,11 @@ private void testVolumeConfig(int volumesTolerated, int 
volumesFailed,
             cluster.getDataNodes().get(0)
                     
.isBPServiceAlive(cluster.getNamesystem().getBlockPoolId());
       }
-      assertEquals(expectedBPServiceState, bpServiceState);
 
       for (File dir : dirs) {
         FileUtil.chmod(dir.toString(), "755");
       }
+      assertEquals(expectedBPServiceState, bpServiceState);
     }
   }
{code}



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-dev-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-dev-h...@hadoop.apache.org

Reply via email to