[STORM-2356] Storm-HDFS: NPE on empty & stale lock file

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.0.0, 1.x
• Component/s: storm-hdfs
• Assignee: Unassigned
• Reporter: Tibor Kiss
• Created: 12/Feb/17 12:38
• Updated: 29/Apr/17 05:25

Description

In HDFSSpout a NPE can occur if a stale lock file is empty.

LogEntry.deserialize tries to split the line by colons.
If the line is null, the split will cause a NPE:
https://github.com/apache/storm/blob/master/external/storm-hdfs/src/main/java/org/apache/storm/hdfs/spout/FileLock.java#L179

Moreover the callee of getLastEntry is also mishandling empty log files.
The lastEntry.eventTime could also cause a NPE if the above scenario is passed and the log file is empty:
https://github.com/apache/storm/blob/master/external/storm-hdfs/src/main/java/org/apache/storm/hdfs/spout/FileLock.java#L149-L160