[Buildbot-devel] Some questions/problems running latest build bot source on Windows

[Brian Warner]

> After doing some more digging, it seems that this is a twisted problem with
> spawnProcess not being implemented in the default reactor on Windows, not a
> buildbot problem.

> I don't know enough about twisted to know whether reactor.spawnProcess() is
> something that is trivial to work around in buildbot, or whether I just need
> to wait for the next twisted release.

Yeah, spawnProcess() is an absolute necessity for the buildslaves. I believe
the existing w32 slaves are using the 'win32' reactor, which does implement
it, so it should be a simple matter of running the slaves under twistd with
the '-r win32' argument (which I think the 'buildbot' script currently does).

You can also run the unit tests under a different reactor by using the same
argument. Give that a try and see if the ShellCommand failures go away.

Alternately, you can grab the latest Twisted from the SVN repository and run
the buildbot against that. I've done this from time to time and I think
everything should work.. there are a handful of DeprecationWarnings, but
that's nust noise. I've been waiting until twisted-2.0 is released before
addressing them, because some of the fixes would make Buildbot incompatible
with Twisted-1.3.0 (and being incompatible with the only official release
would be a drag).


It isn't clear to me why Twisted doesn't default to win32reactor when it
notices that it's running under windows, given that the default reactor seems
less capable. It's possible that there are other problems with the
win32reactor that make it unsuitable.. not sure.

cheers,
 -Brian