airflow/utils/event_scheduler.py

#
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# to you under the Apache License, Version 2.0 (the
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# with the License.  You may obtain a copy of the License at
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#   http://www.apache.org/licenses/LICENSE-2.0
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from __future__ import annotations

from sched import scheduler
from typing import Callable


class EventScheduler(scheduler):
    """General purpose event scheduler."""

    def call_regular_interval(
        self,
        delay: float,
        action: Callable,
        arguments=(),
        kwargs={},
    ):
        """Helper to call a function at (roughly) a given interval."""

        def repeat(*args, **kwargs):
            action(*args, **kwargs)
            # This is not perfect. If we want a timer every 60s, but action
            # takes 10s to run, this will run it every 70s.
            # Good enough for now
            self.enter(delay, 1, repeat, args, kwargs)

        self.enter(delay, 1, repeat, arguments, kwargs)