Source code for aiomisc.cron

import asyncio
import logging
from datetime import datetime, timezone
from functools import partial
from typing import Any, Awaitable, Callable, Optional, Tuple, Type, Union

from croniter import croniter

from .compat import EventLoopMixin
from .recurring import RecurringCallback

log = logging.getLogger(__name__)

[docs]class CronCallback(EventLoopMixin): """ .. note:: When the cron function executes longer then execution interval a next call will be skipping and warning will be logged. """ __slots__ = ("_recurring_cb", "_task") + EventLoopMixin.__slots__ def __init__( self, coroutine_func: Callable[..., Union[Any, Awaitable[Any]]], *args: Any, **kwargs: Any, ): self._recurring_cb = RecurringCallback( coroutine_func, *args, **kwargs, ) self._task: Optional[asyncio.Task] = None
[docs] @staticmethod def get_next(cron: croniter, _: RecurringCallback) -> float: timestamp = next_date = cron.get_next(float, timestamp) return next_date - timestamp
[docs] def start( self, spec: str, loop: Optional[asyncio.AbstractEventLoop] = None, *, shield: bool = False, suppress_exceptions: Tuple[Type[Exception], ...] = (), ) -> None: if self._task and not self._task.done(): raise asyncio.InvalidStateError self._loop = loop # noinspection PyAttributeOutsideInit strategy = partial(self.get_next, croniter(spec)) self._task = self._recurring_cb.start( strategy=strategy, loop=loop, shield=shield, suppress_exceptions=suppress_exceptions, )
[docs] def stop(self) -> asyncio.Future: if self._task is None: task = self.loop.create_future() task.set_exception(RuntimeError("Callback not started")) return task elif not self._task.done(): self._task.cancel() return self._task
def __repr__(self) -> str: return f"<{self.__class__.__name__}({})>"