113 lines
3.9 KiB
Python
113 lines
3.9 KiB
Python
"""轻量级纯内存异步 Worker Pool"""
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import asyncio
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from typing import Callable, Coroutine, List, TypeVar
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from app.core.log import logger
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T = TypeVar("T")
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Handler = Callable[[T], Coroutine[None, None, None]]
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class AsyncWorkerPool:
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"""纯内存异步工作池
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职责单一：接收任务列表 -> 分发给 N 个 Worker 协程 -> 调用 handler 处理
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不包含任何持久化逻辑，也不维护复杂的状态机。
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"""
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def __init__(
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self,
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worker_count: int,
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handler: Handler,
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queue_maxsize: int = 10000,
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name: str = "WorkerPool",
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):
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self.worker_count = worker_count
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self.handler = handler
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self.name = name
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self._queue: asyncio.Queue = asyncio.Queue(maxsize=queue_maxsize)
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self._workers: List[asyncio.Task] = []
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self._running = False
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self._shutdown_event = asyncio.Event()
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async def __aenter__(self):
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await self.start()
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return self
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async def __aexit__(self, exc_type, exc_val, exc_tb):
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await self.stop()
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async def start(self) -> None:
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if self._running:
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return
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self._running = True
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self._shutdown_event.clear()
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self._workers = [
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asyncio.create_task(self._worker_loop(i), name=f"{self.name}-worker-{i}")
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for i in range(self.worker_count)
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]
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logger.info(f"{self.name} started with {self.worker_count} workers")
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async def stop(self) -> None:
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if not self._running:
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return
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self._running = False
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self._shutdown_event.set()
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# 发送足够数量的 sentinel，确保所有 Worker 都能收到
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for _ in range(len(self._workers) + self._queue.qsize()):
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try:
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self._queue.put_nowait(None)
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except asyncio.QueueFull:
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break
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if self._workers:
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await asyncio.gather(*self._workers, return_exceptions=True)
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self._workers.clear()
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logger.info(f"{self.name} stopped")
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async def submit(self, items: List[T]) -> None:
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"""提交一批任务到队列（阻塞直到有空位，天然背压）"""
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for item in items:
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await self._queue.put(item)
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async def drain(self) -> None:
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"""等待队列中所有任务被消费完毕"""
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await self._queue.join()
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async def resize(self, new_worker_count: int) -> None:
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"""动态调整 Worker 数量，不丢失队列中的任务"""
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if new_worker_count == self.worker_count:
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return
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logger.info(f"{self.name} resizing from {self.worker_count} to {new_worker_count}")
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if new_worker_count > self.worker_count:
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for i in range(self.worker_count, new_worker_count):
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self._workers.append(
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asyncio.create_task(self._worker_loop(i), name=f"{self.name}-worker-{i}")
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)
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elif new_worker_count < self.worker_count:
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for _ in range(self.worker_count - new_worker_count):
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await self._queue.put(None)
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await asyncio.sleep(0)
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still_running = []
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for w in self._workers:
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if w.done():
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try:
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await w
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except asyncio.CancelledError:
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pass
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else:
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still_running.append(w)
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self._workers = still_running
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self.worker_count = new_worker_count
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async def _worker_loop(self, worker_id: int) -> None:
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while True:
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item = await self._queue.get()
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try:
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if item is None or not self._running:
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break
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await self.handler(item)
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except Exception as e:
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logger.error(f"{self.name} worker {worker_id} handler error: {e}", exc_info=True)
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finally:
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self._queue.task_done()
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