Source code for aiomisc.periodic

import asyncio
import logging
from typing import Any, Optional, Union

from .compat import EventLoopMixin
from .recurring import CallbackType, ExceptionsType, RecurringCallback

log = logging.getLogger(__name__)

[docs]class PeriodicCallback(EventLoopMixin): """ .. note:: When the periodic function executes longer then execution interval a next call would be skipped and warning would be logged. """ __slots__ = ("_recurring_callback", "_task") + EventLoopMixin.__slots__ _task: Optional[asyncio.Future] def __init__( self, coroutine_func: CallbackType, *args: Any, **kwargs: Any, ): self._recurring_callback: RecurringCallback = RecurringCallback( coroutine_func, *args, **kwargs, ) self._task: Optional[asyncio.Task] = None
[docs] def start( self, interval: Union[int, float], loop: Optional[asyncio.AbstractEventLoop] = None, *, delay: Union[int, float] = 0, shield: bool = False, suppress_exceptions: ExceptionsType = (), ) -> None: assert interval if self._task and not self._task.done(): raise asyncio.InvalidStateError delayed = False def strategy(_: Any) -> Union[int, float]: nonlocal delayed if not delayed: delayed = True return delay return interval self._task = self._recurring_callback.start( strategy=strategy, shield=shield, loop=loop, suppress_exceptions=suppress_exceptions, ) def clean_task(_: Any) -> None: self._task = None self._task.add_done_callback(clean_task)
[docs] def stop(self, return_exceptions: bool = False) -> asyncio.Future: if self._task is None: self._task = self.loop.create_future() self._task.set_exception(RuntimeError("Callback not started")) elif not self._task.done(): self._task.cancel() task, self._task = self._task, None return asyncio.gather(task, return_exceptions=return_exceptions)
def __repr__(self) -> str: return f"{self.__class__.__name__}({})"