[CHUKWA-641] PatternSyntaxException Crash from Unvalidated Regular Expression Usage

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.5.0
• Assignee: Eric Spishak
• Reporter: Eric Spishak
• Created: 09/May/12 00:45
• Updated: 10/May/12 04:52
• Resolved: 10/May/12 04:25

Description

Chukwa sometimes crashes with an unhelpful stack trace. In particular, a PatternSyntaxException is thrown when an invalid regular expression is passed to the dumpChunk command. This exception isn't useful to users to diagnose the error. I think it would be better to report a detailed error message. The attached patch makes this change.

Steps to reproduce:

1. Run 'bin/chukwa dumpChunk "tags.=(" file'
2. dumpChunk command fails to start
3. See exception:

Exception in thread "main" java.util.regex.PatternSyntaxException:
Unclosed group near index 1
(
 ^
       at java.util.regex.Pattern.error(Pattern.java:1713)
       at java.util.regex.Pattern.accept(Pattern.java:1571)
       at java.util.regex.Pattern.group0(Pattern.java:2533)
       at java.util.regex.Pattern.sequence(Pattern.java:1806)
       at java.util.regex.Pattern.expr(Pattern.java:1752)
       at java.util.regex.Pattern.compile(Pattern.java:1460)
       at java.util.regex.Pattern.<init>(Pattern.java:1133)
       at java.util.regex.Pattern.compile(Pattern.java:847)
       at org.apache.hadoop.chukwa.util.Filter.<init>(Filter.java:94)
       at org.apache.hadoop.chukwa.util.DumpChunks.dump(DumpChunks.java:88)
       at org.apache.hadoop.chukwa.util.DumpChunks.main(DumpChunks.java:53)

After applying the supplied patch the output is:

Error parsing "tags" regular expression: Unclosed group near index 1
(
 ^