| """ |
| Copyright (c) 2003-2005 Gustavo Niemeyer <gustavo@niemeyer.net> |
| |
| This module offers extensions to the standard python 2.3+ |
| datetime module. |
| """ |
| __author__ = "Gustavo Niemeyer <gustavo@niemeyer.net>" |
| __license__ = "PSF License" |
| |
| import datetime |
| import _thread |
| import signal |
| import time |
| |
| class sched(object): |
| |
| def __init__(self, rrule, |
| tolerance=None, last=None, |
| execute=None, args=None, kwargs=None): |
| self._rrule = rrule |
| if tolerance: |
| self._tolerance = datetime.timedelta(seconds=tolerance) |
| else: |
| self._tolerance = None |
| self._last = last |
| self._execute = execute |
| self._args = args or () |
| self._kwargs = kwargs or {} |
| |
| def last(self): |
| return self._last |
| |
| def next(self, now=None): |
| if not now: |
| now = datetime.datetime.now() |
| return self._rrule.after(now) |
| |
| def check(self, now=None, readonly=False): |
| if not now: |
| now = datetime.datetime.now() |
| item = self._rrule.before(now, inc=True) |
| if (item is None or item == self._last or |
| (self._tolerance and item+self._tolerance < now)): |
| return None |
| if not readonly: |
| self._last = item |
| if self._execute: |
| self._execute(*self._args, **self._kwargs) |
| return item |
| |
| |
| class schedset(object): |
| def __init__(self): |
| self._scheds = [] |
| |
| def add(self, sched): |
| self._scheds.append(sched) |
| |
| def next(self, now=None): |
| if not now: |
| now = datetime.datetime.now() |
| res = None |
| for sched in self._scheds: |
| next = sched.next(now) |
| if next and (not res or next < res): |
| res = next |
| return res |
| |
| def check(self, now=None, readonly=False): |
| if not now: |
| now = datetime.datetime.now() |
| res = False |
| for sched in self._scheds: |
| if sched.check(now, readonly): |
| res = True |
| return res |
| |
| |
| class schedthread(object): |
| |
| def __init__(self, sched, lock=None): |
| self._sched = sched |
| self._lock = lock |
| self._running = False |
| |
| def running(self): |
| return self._running |
| |
| def run(self): |
| self._running = True |
| _thread.start_new_thread(self._loop, ()) |
| |
| def stop(self): |
| self._running = False |
| |
| def _loop(self): |
| while self._running: |
| if self._lock: |
| self._lock.acquire() |
| now = datetime.datetime.now() |
| self._sched.check(now) |
| if self._lock: |
| self._lock.release() |
| seconds = _seconds_left(self._sched.next(now)) |
| if seconds is None: |
| self._running = False |
| break |
| if self._running: |
| time.sleep(seconds) |
| |
| |
| class schedalarm(object): |
| |
| def __init__(self, sched, lock=None): |
| self._sched = sched |
| self._lock = lock |
| self._running = False |
| |
| def running(self): |
| return self._running |
| |
| def run(self): |
| self._running = True |
| signal.signal(signal.SIGALRM, self._handler) |
| self._handler(None, None) |
| |
| def stop(self): |
| self._running = False |
| |
| def _handler(self, sig, frame): |
| while self._running: |
| if self._lock: |
| self._lock.acquire() |
| now = datetime.datetime.now() |
| self._sched.check(now) |
| if self._lock: |
| self._lock.release() |
| if self._running: |
| seconds = _seconds_left(self._sched.next(now)) |
| if seconds: |
| signal.alarm(seconds) |
| break |
| elif seconds is None: |
| self._running = False |
| break |
| |
| |
| def _seconds_left(next): |
| if not next: |
| return None |
| now = datetime.datetime.now() |
| delta = next-now |
| seconds = delta.days*86400+delta.seconds |
| if seconds < 0: |
| seconds = 0 |
| return seconds |
| |