Hello!
Over the last few weeks, Yusuke Matsubara, Shawn Walker, Aaron Halfaker and
Fabian Kaelin (who are all Summer of Research fellows)[0] have worked hard
on a customized stream-based InputFormatReader that allows parsing of both
bz2 compressed and uncompressed files of the full Wikipedia dump (dump file
with the complete edit histories) using Hadoop. Prior to WikiHadoop and the
accompanying InputFormatReader it was not possible to use Hadoop to analyze
the full Wikipedia dump files (see the detailed tutorial / background for an
explanation why that was not possible).
This means:
1) We can now harness Hadoop's distributed computing capabilities in
analyzing the full dump files.
2) You can send either one or two revisions to a single mapper so it's
possible to diff two revisions and see what content has been addded /
removed.
3) You can exclude namespaces by supplying a regular expression.
4) We are using Hadoop's Streaming interface which means people can use this
InputFormat Reader using different languages such as Java, Python, Ruby and
PHP.
The source code is available at:
https://github.com/whym/wikihadoop
A more detailed tutorial and installation guide is available at:
https://github.com/whym/wikihadoop/wiki
(Apologies for cross-posting to wikitech-l and wiki-research-l)
[0]
http://blog.wikimedia.org/2011/06/01/summerofresearchannouncement/
Best,
Diederik