View source for ReleaseEngineering/Upgrading Buildbot

= Structure =

Mozilla's copy of Buildbot is at http://hg.mozilla.org/build/buildbot.  There are two branches in this repository - ''upstream'' and ''default''.  The former is basically a copy of the Buildbot source from git, while the latter is the locally patched version.

If you have a look at the revision graph, you'll see that ''upstream'' gets updated with each new buildbot release, then merged into ''default''.

= Upgrading Process =

Get a copy of upstream Buildbot from a tag, as a tarball.  The easiest way is to go to the '[https://github.com/buildbot/buildbot/downloads downloads]' page on github and download the appropriate tarball.  You can also make a clone and use ''git archive''.

In a checkout of ''build/buildbot'',
* switch to the ''upstream'' branch,
* ''rm -rf'' everything,
* untar the tarball, and 
* use ''hg addremove'' to process any added or removed files.  

Commit with a message like "Imported Buildbot-0.8.2 source", then tag with e.g., ''BUILDBOT_0_8_2''.

Switch to the ''default'' branch and use ''hg merge'' to merge the changes.  Resolve any conflicts (bearing in mind that they may be significant, rather than merely textual).

:'''IMPORTANT''': edit ''master/buildbot/VERSION'' and ''slave/buildslave/VERSION'' to reflect the new version -- Buildbot's usual tactic of using ''git describe'' to determine the version doesn't work with hg.

Commit your updates to ''default''.  That's it - now it's time to test!

== Staging a New Master ==
On a staging machine, 
* clone your hg repo into ''/tmp'' or somewhere convenient
* create a new virtualenv in /tools:
  /tools/python-2.6.5/bin/virtualenv /tools/buildbot-0.8.2
* activate it
  source /tools/buildbot-0.8.2/bin/activate
* install the buildbot (master) package
  cd master/
  python setup.py install

At the momemnt, you'll also need to install some prereqs for buildbotconfig using ''easy_install'' (see {{bug|608296}}):
 * pycrypto
 * pyasn1
 * argparse

Back in your staging directory, edit the Makefile to point it at the new version:
  BUILDBOT=/tools/buildbot-0.8.2/bin/buildbot

that's it - ''make restart'' and check the /about URI to make sure it upgraded (and that you remembered to change VERSION).  You will probably need to run ''buildbot upgrade-master'' to upgrade the database first, but the buildmaster will tell you that.