Package org.apache.storm.utils

Class HadoopLoginUtil

java.lang.Object

org.apache.storm.utils.HadoopLoginUtil

public class HadoopLoginUtil
extends Object

UserGroupInformation#loginUserFromKeytab(String, String) changes the static fields of UserGroupInformation, especially the current logged-in user, and UserGroupInformation itself is not thread-safe. So it could introduce bugs if it is called multiple times in a JVM process. HadoopLoginUtil.loginHadoop guarantees at-most-once login in a JVM process. This should only be used on the daemon side.

Constructor Summary

Constructors

Constructor	Description
HadoopLoginUtil()

Method Summary

Modifier and Type	Method	Description
static Subject	loginHadoop(Map<String,Object> conf)	Login if a HDFS keytab/principal have been supplied; otherwise, assume it's already logged in or running on insecure HDFS.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

HadoopLoginUtil

public HadoopLoginUtil()

Method Details

loginHadoop

public static Subject loginHadoop(Map<String,Object> conf)

Login if a HDFS keytab/principal have been supplied; otherwise, assume it's already logged in or running on insecure HDFS. This also guarantees that login only happens at most once.

Parameters:

conf - the daemon conf

Returns:

the logged in subject or null