[HDFS-14661] RBF: updateMountTableEntry shouldn't update mountTableEntry if targetPath not exist

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.1.2
• Fix Version/s: 3.3.0
• Component/s: rbf
• Hadoop Flags: Reviewed
• Assignee: ZanderXu
• Reporter: ZanderXu
• Created: 22/Jul/19 13:46
• Updated: 01/Aug/19 03:50
• Resolved: 01/Aug/19 03:38

Description

The updateMountTableEntry shouldn't update the mountEntry if the targetPath not exist.

@Override
public UpdateMountTableEntryResponse updateMountTableEntry(
    UpdateMountTableEntryRequest request) throws IOException {
  UpdateMountTableEntryResponse response =
      getMountTableStore().updateMountTableEntry(request);

  MountTable mountTable = request.getEntry();
  if (mountTable != null && router.isQuotaEnabled()) {
    synchronizeQuota(mountTable.getSourcePath(),
        mountTable.getQuota().getQuota(),
        mountTable.getQuota().getSpaceQuota());
  }
  return response;
}

/**
 * Synchronize the quota value across mount table and subclusters.
 * @param path Source path in given mount table.
 * @param nsQuota Name quota definition in given mount table.
 * @param ssQuota Space quota definition in given mount table.
 * @throws IOException
 */
private void synchronizeQuota(String path, long nsQuota, long ssQuota)
    throws IOException {
  if (router.isQuotaEnabled() &&
      (nsQuota != HdfsConstants.QUOTA_DONT_SET
      || ssQuota != HdfsConstants.QUOTA_DONT_SET)) {
    HdfsFileStatus ret = this.router.getRpcServer().getFileInfo(path);
    if (ret != null) {
      this.router.getRpcServer().getQuotaModule().setQuota(path, nsQuota,
          ssQuota, null);
    }
  }
}

As above, updateMountTableEntry update one mountEntry:

1. update mountEntry in zookeeper
2. synchronizeQuota(maybe throw some exception like "Directory does not exist")

 

if  synchronizeQuota throw some exception, will return some exception to dfsRouterAdmin, but the new mountEntry has been updated to zk.  

It's clearly not what we would expect.