Hive 0.11 升级踩坑记――HiveServer2的imperson问题

前阶段线上在做Hive升级（CDH4.2.0 Hive 0.10――> Apache Hive0.11 with our patches）和Shark上线踩了不少坑，先来说一个Hiveserver的问题.

beeline进入后随便执行一个查询就会报错：

USERxxx don’t have write privilegs under /tmp/hive-hdfs

不对啊，已经启用了impersonation怎么还会去hdfs下的scratchdir写入临时文件呢？查看下代码发现原来CDH4.2的Hive的impersonation和hive0.11在这处的判断行为是不同的：

Hive0.11 apache：只有在启用kerberos才使用hive-xxx作为scratchdir否则使用hiveserver的start user的scratchdir

if (
        cliService.getHiveConf().getVar(ConfVars.HIVE_SERVER2_AUTHENTICATION)
        .equals(HiveAuthFactory.AuthTypes.KERBEROS.toString())
        &&
        cliService.getHiveConf().
        getBoolVar(ConfVars.HIVE_SERVER2_ENABLE_DOAS)
        )
    {
      String delegationTokenStr = null;
      try {
        delegationTokenStr = cliService.getDelegationTokenFromMetaStore(userName);
      } catch (UnsupportedOperationException e) {
        // The delegation token is not applicable in the given deployment mode
      }
      sessionHandle = cliService.openSessionWithImpersonation(userName, req.getPassword(),
            req.getConfiguration(), delegationTokenStr);
    } else {
      sessionHandle = cliService.openSession(userName, req.getPassword(),
            req.getConfiguration());
    }

Cloudera4.2.0的Hive0.10是只要启用了impersonation就使用独自的scratchdir...

if (cliService.getHiveConf().
          getBoolVar(HiveConf.ConfVars.HIVE_SERVER2_KERBEROS_IMPERSONATION)) {
        String delegationTokenStr = null;
        try {
          delegationTokenStr = cliService.getDelegationTokenFromMetaStore(userName);
        } catch (UnsupportedOperationException e) {
          // The delegation token is not applicable in the given deployment mode
        }
        sessionHandle = cliService.openSessionWithImpersonation(userName, req.getPassword(),
              req.getConfiguration(), delegationTokenStr);
      } else {
        sessionHandle = cliService.openSession(userName, req.getPassword(),
              req.getConfiguration());
      }

并且这个作为一个Hiveserver的bug在0.13被修复：https://issues.apache.org/jira/browse/HIVE-5486

workaround也简单，就是把/tmp/hive-hdfs改成777就好了=。=坑爹啊