The master.cfg configuration file has a dictionary key named
BuildmasterConfig['change_source'], which holds the active
IChangeSource object. The config file will typically create an
object from one of the classes described below and stuff it into this
key.
Each buildmaster typically has just a single ChangeSource, since it is
only watching a single source tree. But if, for some reason, you need
multiple sources, just set c['change_source'] to a list of
ChangeSources.
s = FreshCVSSourceNewcred(host="host", port=4519,
user="alice", passwd="secret",
prefix="Twisted")
c['change_source'] = [s]
Each source tree has a nominal top. Each Change has a list of
filenames, which are all relative to this top location. The
ChangeSource is responsible for doing whatever is necessary to
accomplish this. Most sources have a prefix argument: a partial
pathname which is stripped from the front of all filenames provided to
that ChangeSource. Files which are outside this sub-tree are
ignored by the changesource: it does not generate Changes for those
files.
ChangeSources will, in general, automatically provide the proper 'repository' attribute for any changes they produce. For systems which operate on URL-like specifiers, this is a repository URL. Other ChangeSources adapt the concept as necessary.
Many ChangeSources allow you to specify a project, as well. This attribute is useful when building from several distinct codebases in the same buildmaster: the project string can serve to differentiate the different codebases. Schedulers can filter on project, so you can configure different builders to run for each project.