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Diffstat (limited to '.venv/lib/python3.12/site-packages/anyio/to_process.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/anyio/to_process.py | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/anyio/to_process.py b/.venv/lib/python3.12/site-packages/anyio/to_process.py new file mode 100644 index 00000000..495de2ae --- /dev/null +++ b/.venv/lib/python3.12/site-packages/anyio/to_process.py @@ -0,0 +1,258 @@ +from __future__ import annotations + +import os +import pickle +import subprocess +import sys +from collections import deque +from collections.abc import Callable +from importlib.util import module_from_spec, spec_from_file_location +from typing import TypeVar, cast + +from ._core._eventloop import current_time, get_async_backend, get_cancelled_exc_class +from ._core._exceptions import BrokenWorkerProcess +from ._core._subprocesses import open_process +from ._core._synchronization import CapacityLimiter +from ._core._tasks import CancelScope, fail_after +from .abc import ByteReceiveStream, ByteSendStream, Process +from .lowlevel import RunVar, checkpoint_if_cancelled +from .streams.buffered import BufferedByteReceiveStream + +if sys.version_info >= (3, 11): + from typing import TypeVarTuple, Unpack +else: + from typing_extensions import TypeVarTuple, Unpack + +WORKER_MAX_IDLE_TIME = 300 # 5 minutes + +T_Retval = TypeVar("T_Retval") +PosArgsT = TypeVarTuple("PosArgsT") + +_process_pool_workers: RunVar[set[Process]] = RunVar("_process_pool_workers") +_process_pool_idle_workers: RunVar[deque[tuple[Process, float]]] = RunVar( + "_process_pool_idle_workers" +) +_default_process_limiter: RunVar[CapacityLimiter] = RunVar("_default_process_limiter") + + +async def run_sync( # type: ignore[return] + func: Callable[[Unpack[PosArgsT]], T_Retval], + *args: Unpack[PosArgsT], + cancellable: bool = False, + limiter: CapacityLimiter | None = None, +) -> T_Retval: + """ + Call the given function with the given arguments in a worker process. + + If the ``cancellable`` option is enabled and the task waiting for its completion is + cancelled, the worker process running it will be abruptly terminated using SIGKILL + (or ``terminateProcess()`` on Windows). + + :param func: a callable + :param args: positional arguments for the callable + :param cancellable: ``True`` to allow cancellation of the operation while it's + running + :param limiter: capacity limiter to use to limit the total amount of processes + running (if omitted, the default limiter is used) + :return: an awaitable that yields the return value of the function. + + """ + + async def send_raw_command(pickled_cmd: bytes) -> object: + try: + await stdin.send(pickled_cmd) + response = await buffered.receive_until(b"\n", 50) + status, length = response.split(b" ") + if status not in (b"RETURN", b"EXCEPTION"): + raise RuntimeError( + f"Worker process returned unexpected response: {response!r}" + ) + + pickled_response = await buffered.receive_exactly(int(length)) + except BaseException as exc: + workers.discard(process) + try: + process.kill() + with CancelScope(shield=True): + await process.aclose() + except ProcessLookupError: + pass + + if isinstance(exc, get_cancelled_exc_class()): + raise + else: + raise BrokenWorkerProcess from exc + + retval = pickle.loads(pickled_response) + if status == b"EXCEPTION": + assert isinstance(retval, BaseException) + raise retval + else: + return retval + + # First pickle the request before trying to reserve a worker process + await checkpoint_if_cancelled() + request = pickle.dumps(("run", func, args), protocol=pickle.HIGHEST_PROTOCOL) + + # If this is the first run in this event loop thread, set up the necessary variables + try: + workers = _process_pool_workers.get() + idle_workers = _process_pool_idle_workers.get() + except LookupError: + workers = set() + idle_workers = deque() + _process_pool_workers.set(workers) + _process_pool_idle_workers.set(idle_workers) + get_async_backend().setup_process_pool_exit_at_shutdown(workers) + + async with limiter or current_default_process_limiter(): + # Pop processes from the pool (starting from the most recently used) until we + # find one that hasn't exited yet + process: Process + while idle_workers: + process, idle_since = idle_workers.pop() + if process.returncode is None: + stdin = cast(ByteSendStream, process.stdin) + buffered = BufferedByteReceiveStream( + cast(ByteReceiveStream, process.stdout) + ) + + # Prune any other workers that have been idle for WORKER_MAX_IDLE_TIME + # seconds or longer + now = current_time() + killed_processes: list[Process] = [] + while idle_workers: + if now - idle_workers[0][1] < WORKER_MAX_IDLE_TIME: + break + + process_to_kill, idle_since = idle_workers.popleft() + process_to_kill.kill() + workers.remove(process_to_kill) + killed_processes.append(process_to_kill) + + with CancelScope(shield=True): + for killed_process in killed_processes: + await killed_process.aclose() + + break + + workers.remove(process) + else: + command = [sys.executable, "-u", "-m", __name__] + process = await open_process( + command, stdin=subprocess.PIPE, stdout=subprocess.PIPE + ) + try: + stdin = cast(ByteSendStream, process.stdin) + buffered = BufferedByteReceiveStream( + cast(ByteReceiveStream, process.stdout) + ) + with fail_after(20): + message = await buffered.receive(6) + + if message != b"READY\n": + raise BrokenWorkerProcess( + f"Worker process returned unexpected response: {message!r}" + ) + + main_module_path = getattr(sys.modules["__main__"], "__file__", None) + pickled = pickle.dumps( + ("init", sys.path, main_module_path), + protocol=pickle.HIGHEST_PROTOCOL, + ) + await send_raw_command(pickled) + except (BrokenWorkerProcess, get_cancelled_exc_class()): + raise + except BaseException as exc: + process.kill() + raise BrokenWorkerProcess( + "Error during worker process initialization" + ) from exc + + workers.add(process) + + with CancelScope(shield=not cancellable): + try: + return cast(T_Retval, await send_raw_command(request)) + finally: + if process in workers: + idle_workers.append((process, current_time())) + + +def current_default_process_limiter() -> CapacityLimiter: + """ + Return the capacity limiter that is used by default to limit the number of worker + processes. + + :return: a capacity limiter object + + """ + try: + return _default_process_limiter.get() + except LookupError: + limiter = CapacityLimiter(os.cpu_count() or 2) + _default_process_limiter.set(limiter) + return limiter + + +def process_worker() -> None: + # Redirect standard streams to os.devnull so that user code won't interfere with the + # parent-worker communication + stdin = sys.stdin + stdout = sys.stdout + sys.stdin = open(os.devnull) + sys.stdout = open(os.devnull, "w") + + stdout.buffer.write(b"READY\n") + while True: + retval = exception = None + try: + command, *args = pickle.load(stdin.buffer) + except EOFError: + return + except BaseException as exc: + exception = exc + else: + if command == "run": + func, args = args + try: + retval = func(*args) + except BaseException as exc: + exception = exc + elif command == "init": + main_module_path: str | None + sys.path, main_module_path = args + del sys.modules["__main__"] + if main_module_path and os.path.isfile(main_module_path): + # Load the parent's main module but as __mp_main__ instead of + # __main__ (like multiprocessing does) to avoid infinite recursion + try: + spec = spec_from_file_location("__mp_main__", main_module_path) + if spec and spec.loader: + main = module_from_spec(spec) + spec.loader.exec_module(main) + sys.modules["__main__"] = main + except BaseException as exc: + exception = exc + try: + if exception is not None: + status = b"EXCEPTION" + pickled = pickle.dumps(exception, pickle.HIGHEST_PROTOCOL) + else: + status = b"RETURN" + pickled = pickle.dumps(retval, pickle.HIGHEST_PROTOCOL) + except BaseException as exc: + exception = exc + status = b"EXCEPTION" + pickled = pickle.dumps(exc, pickle.HIGHEST_PROTOCOL) + + stdout.buffer.write(b"%s %d\n" % (status, len(pickled))) + stdout.buffer.write(pickled) + + # Respect SIGTERM + if isinstance(exception, SystemExit): + raise exception + + +if __name__ == "__main__": + process_worker() |