57 lines
1.9 KiB
Python
57 lines
1.9 KiB
Python
"""
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MaiSaka - 异步输入读取器
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将阻塞的标准输入读取放到后台线程中，供 asyncio 循环安全消费。
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"""
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import asyncio
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import sys
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import threading
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from typing import Optional
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class InputReader:
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"""后台读取标准输入，并通过 asyncio.Queue 向主循环投递结果。"""
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def __init__(self) -> None:
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self._loop: Optional[asyncio.AbstractEventLoop] = None
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self._queue: asyncio.Queue[Optional[str]] = asyncio.Queue()
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self._thread: Optional[threading.Thread] = None
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self._stop_event = threading.Event()
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def start(self, loop: asyncio.AbstractEventLoop) -> None:
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"""启动后台输入线程。重复调用时忽略。"""
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if self._thread and self._thread.is_alive():
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return
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self._loop = loop
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self._stop_event.clear()
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self._thread = threading.Thread(target=self._read_loop, name="maisaka-input-reader", daemon=True)
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self._thread.start()
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def _read_loop(self) -> None:
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"""在后台线程中阻塞读取 stdin。"""
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while not self._stop_event.is_set():
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line = sys.stdin.readline()
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if self._loop is None:
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return
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if line == "":
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self._loop.call_soon_threadsafe(self._queue.put_nowait, None)
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return
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self._loop.call_soon_threadsafe(self._queue.put_nowait, line.rstrip("\r\n"))
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async def get_line(self, timeout: Optional[int] = None) -> Optional[str]:
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"""异步获取一行输入；设置 timeout 时支持超时返回。"""
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if timeout is None:
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return await self._queue.get()
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try:
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return await asyncio.wait_for(self._queue.get(), timeout=timeout)
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except asyncio.TimeoutError:
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return None
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def close(self) -> None:
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"""请求后台线程停止。"""
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self._stop_event.set()
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