[HADOOP-8229] DistCp doesn't handle non-existent paths correctly

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 0.20.2, 1.0.0
• Assignee: Unassigned
• Reporter: Jakob Homan
• Created: 29/Mar/12 22:09
• Updated: 31/Jul/14 22:23
• Resolved: 31/Jul/14 22:23

Description

Assume /user/jhoman/blork doesn't exist:

[tardis]$ hadoop distcp 'hftp://nn:50070/user/jhoman/blork' /tmp/plork
12/03/29 22:04:33 INFO tools.DistCp: srcPaths=[hftp://nn:50070/user/jhoman/blork]
12/03/29 22:04:33 INFO tools.DistCp: destPath=/tmp/plork
[Fatal Error] :1:173: XML document structures must start and end within the same entity.
With failures, global counters are inaccurate; consider running with -i
Copy failed: java.io.IOException: invalid xml directory content
	at org.apache.hadoop.hdfs.HftpFileSystem$LsParser.fetchList(HftpFileSystem.java:427)
	at org.apache.hadoop.hdfs.HftpFileSystem$LsParser.getFileStatus(HftpFileSystem.java:432)
	at org.apache.hadoop.hdfs.HftpFileSystem.getFileStatus(HftpFileSystem.java:461)
	at org.apache.hadoop.fs.FileSystem.exists(FileSystem.java:768)
	at org.apache.hadoop.tools.DistCp.checkSrcPath(DistCp.java:636)
	at org.apache.hadoop.tools.DistCp.copy(DistCp.java:656)
	at org.apache.hadoop.tools.DistCp.run(DistCp.java:881)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
	at org.apache.hadoop.tools.DistCp.main(DistCp.java:908)
Caused by: org.xml.sax.SAXParseException: XML document structures must start and end within the same entity.
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1231)
	at org.apache.hadoop.hdfs.HftpFileSystem$LsParser.fetchList(HftpFileSystem.java:421)
	... 9 more

This is because the ListPathsServlet hits an NPE when it calls nnproxy.getFileInfo(path); on the non-existent path and just bails, leaving the resulting XML unformed.