4.6.5 PBChangeSource

The last kind of ChangeSource actually listens on a TCP port for clients to connect and push change notices into the Buildmaster. This is used by the built-in buildbot sendchange notification tool, as well as the VC-specific contrib/svn_buildbot.py, contrib/arch_buildbot.py, contrib/hg_buildbot.py tools, and the buildbot.changes.hgbuildbot hook. These tools are run by the repository (in a commit hook script), and connect to the buildmaster directly each time a file is comitted. This is also useful for creating new kinds of change sources that work on a push model instead of some kind of subscription scheme, for example a script which is run out of an email .forward file.

This ChangeSource can be configured to listen on its own TCP port, or it can share the port that the buildmaster is already using for the buildslaves to connect. (This is possible because the PBChangeSource uses the same protocol as the buildslaves, and they can be distinguished by the username attribute used when the initial connection is established). It might be useful to have it listen on a different port if, for example, you wanted to establish different firewall rules for that port. You could allow only the SVN repository machine access to the PBChangeSource port, while allowing only the buildslave machines access to the slave port. Or you could just expose one port and run everything over it. Note: this feature is not yet implemented, the PBChangeSource will always share the slave port and will always have a user name of change, and a passwd of changepw. These limitations will be removed in the future..

The PBChangeSource is created with the following arguments. All are optional.

‘port’

which port to listen on. If None (which is the default), it shares the port used for buildslave connections. Not Implemented, always set to None.

‘user and passwd’

The user/passwd account information that the client program must use to connect. Defaults to change and changepw. Not Implemented, user is currently always set to change, passwd is always set to changepw.

‘prefix’

The prefix to be found and stripped from filenames delivered over the connection. Any filenames which do not start with this prefix will be removed. If all the filenames in a given Change are removed, the that whole Change will be dropped. This string should probably end with a directory separator.

This is useful for changes coming from version control systems that represent branches as parent directories within the repository (like SVN and Perforce). Use a prefix of 'trunk/' or 'project/branches/foobranch/' to only follow one branch and to get correct tree-relative filenames. Without a prefix, the PBChangeSource will probably deliver Changes with filenames like trunk/foo.c instead of just foo.c. Of course this also depends upon the tool sending the Changes in (like buildbot sendchange) and what filenames it is delivering: that tool may be filtering and stripping prefixes at the sending end.

The following hooks are useful for sending changes to a PBChangeSource:

• Mercurial Hook
• Bzr Hook