54 lines
1.5 KiB
Python
54 lines
1.5 KiB
Python
# Copyright (c) 2022 Tulir Asokan
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#
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# This Source Code Form is subject to the terms of the Mozilla Public
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# License, v. 2.0. If a copy of the MPL was not distributed with this
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# file, You can obtain one at http://mozilla.org/MPL/2.0/.
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from __future__ import annotations
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import asyncio
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import logging
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class SimpleLock:
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_event: asyncio.Event
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log: logging.Logger | None
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message: str | None
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noop_mode: bool
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def __init__(
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self,
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message: str | None = None,
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log: logging.Logger | None = None,
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noop_mode: bool = False,
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) -> None:
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self.noop_mode = noop_mode
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if not noop_mode:
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self._event = asyncio.Event()
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self._event.set()
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self.log = log
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self.message = message
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def __enter__(self) -> None:
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if not self.noop_mode:
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self._event.clear()
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async def __aenter__(self) -> None:
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self.__enter__()
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def __exit__(self, exc_type, exc_val, exc_tb) -> None:
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if not self.noop_mode:
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self._event.set()
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def __aexit__(self, exc_type, exc_val, exc_tb) -> None:
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self.__exit__(exc_type, exc_val, exc_tb)
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@property
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def locked(self) -> bool:
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return not self.noop_mode and not self._event.is_set()
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async def wait(self, task: str | None = None) -> None:
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if self.locked:
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if self.log and self.message:
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self.log.debug(self.message, task)
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await self._event.wait()
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