====================== Mailman runner control ====================== Mailman has a number of *runner subprocesses* which perform long-running tasks such as listening on an LMTP port, processing REST API requests, or processing messages in a queue directory. In normal operation, the ``mailman`` command is used to start, stop and manage the runners. This is just a wrapper around the real master watcher, which handles runner starting, stopping, exiting, and log file reopening. >>> from mailman.testing.helpers import TestableMaster Start the master in a sub-thread. >>> master = TestableMaster() >>> master.start() There should be a process id for every runner that claims to be startable. >>> from lazr.config import as_boolean >>> startable_runners = [conf for conf in config.runner_configs ... if as_boolean(conf.start)] >>> len(list(master.runner_pids)) == len(startable_runners) True Now verify that all the runners are running. :: >>> import os # This should produce no output. >>> for pid in master.runner_pids: ... os.kill(pid, 0) Stop the master process, which should also kill (and not restart) the child runner processes. >>> master.stop() None of the children are running now. >>> import errno >>> for pid in master.runner_pids: ... try: ... os.kill(pid, 0) ... print('Process did not exit:', pid) ... except OSError as error: ... if error.errno == errno.ESRCH: ... # The child process exited. ... pass ... else: ... raise