interrupt.py

"""
Interruptible worker pattern
"""

import threading

class Worker(object):
    def __init__(self):
        self._running = False
        self._wakeup = threading.Condition()

    def start(self):
        with self._wakeup:
            if self._running:
                raise RuntimeError

            self._running = True
            self._thread = threading.Thread(target=self._run)
            self._thread.start()

    def stop(self):
        with self._wakeup:
            if not self._running:
                raise RuntimeError

            self._running = False
            self._wakeup.notify_all()

        self._thread.join()

    def _run(self):
        while self._running:
            # Do our task
            self.do_actual_work()

            # Sleep for five seconds before trying to do more work
            with self._wakeup:
                self._wakeup.wait(5.0)