Add support for Fossil SCM distributed version control system

[dclark]

(just opening a ticket for myself to track progress on this)

• djbclark | desai: Is the abstracted VCS stuff in the current 1.0rc2? I may have a go at writting support for Fossil SCM sometime soonish (context: ​http://code.autonomo.us )
• desai | yeah, it is
• desai | there is a discrete plugin type that handles them now
• desai | see src/lib/Server/Plugins/{SVN,Git}.py for examples

Also wiki:Plugins/Git? , wiki:Plugins/Svn?

[dclark]

This looks *really* easy on the bcfg2 side. Waiting for answer to query regarding "fossil info" / getting version information on checked-out files from the fossil-users list:

• ​http://thread.gmane.org/gmane.comp.version-control.fossil-scm.user/953

[dclark]

Mailing list thread now has a bunch of responses. I think the most efficient way of doing this, while covering all cases, is going to be:

1. At start, run "fossil extra", which will give a list of files not checked in, like:

   doc/notinrepo.txt
   notinrepo2.txt
   

And put into python data structure.

2. At start, run "fossil changes", which will give a list of checked in but changed files, like:

   EDITED   card/casper-rw/MEMBERCARD-README.sh
   EDITED   doc/fsf-membercard.leo
   

And put into python data structure.

3. On each file, run "fossil test-sha1sum fqfn", which will give sha1sum of any file, no matter repo status, like:

   $ fossil test-sha1sum rms-copyright_versus_community_in_the_age_of_computer_networks.spx
   0c9d3cd1e59871f52c7eb4fff0ea573943423771  rms-copyright_versus_community_in_the_age_of_computer_networks.spx
   

4. If file name is not in either of the data structures, just return the sha1sum value.

5. If file name is in extra, return sha1sum with prefix "EXTRA-"

6. If file name is in changes, return sha1sum with prefix of first piece of text, such as "EDITED-"

[dclark]

Turns out this was even easier than I was thinking - Bcfg2 just gets the version for the entire checkout, not per-file versions; I guess it's the sys admin's job to make sure edits/additions are never made to the repository being used :-)

Initial version committed in r5457 - testing tomorrow night...

[dclark]

Need to doc to page linked to from ​https://trac.mcs.anl.gov/projects/bcfg2/wiki/Plugins after testing.

[dclark]

I think this is working and doc'ed in version control in r5462 and later. Also updated wiki.