pombredanne / pyat

Python scheduler interface

pyat

pyat is the Python analogue of the Unix at daemon, it runs tasks at specified times, optionally providing a means to pass around results and exceptions.

The interface is intended to be able to support a variety of usage scenarios including synchronous applications with a main loop, sporadically called functions, multithreadded/multiprocessing based code and asynchronous frameworks like Twisted or Tornado.

REQUIREMENTS

• six

TYPICAL USAGE

import pyat.sync
import time

scheduler = pyat.sync.SynchronousScheduler()

# ... etc ...

background_task = None

while True:
    # ... etc ...

    scheduler.poll()

    if foo == bar:
        # Do something in 10 seconds.
        background_task = scheduler.schedule(
            time.time() + 10, my_task, arg1, arg2, kwarg1=arg3)

    elif foo == baz:
        # Cancel task
        background_task.cancel()
        background_task = None

    elif (foo == quux) and (background_task is not None):
        # Check back on background task
        try:
            result = background_task.result
            # do something with result
            background_task = None
        except pyat.sync.NotExecutedYet:
            # A bit too early
            pass

STATUS

• Synchronous implementation pyat.sync works.