Initial commit

download-backend/.venv/lib/python3.12/site-packages/anyio/to_interpreter.py

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+from __future__ import annotations
+
+import atexit
+import os
+import sys
+from collections import deque
+from collections.abc import Callable
+from typing import Any, Final, TypeVar
+
+from . import current_time, to_thread
+from ._core._exceptions import BrokenWorkerInterpreter
+from ._core._synchronization import CapacityLimiter
+from .lowlevel import RunVar
+
+if sys.version_info >= (3, 11):
+    from typing import TypeVarTuple, Unpack
+else:
+    from typing_extensions import TypeVarTuple, Unpack
+
+if sys.version_info >= (3, 14):
+    from concurrent.interpreters import ExecutionFailed, create
+
+    def _interp_call(func: Callable[..., Any], args: tuple[Any, ...]):
+        try:
+            retval = func(*args)
+        except BaseException as exc:
+            return exc, True
+        else:
+            return retval, False
+
+    class Worker:
+        last_used: float = 0
+
+        def __init__(self) -> None:
+            self._interpreter = create()
+
+        def destroy(self) -> None:
+            self._interpreter.close()
+
+        def call(
+            self,
+            func: Callable[..., T_Retval],
+            args: tuple[Any, ...],
+        ) -> T_Retval:
+            try:
+                res, is_exception = self._interpreter.call(_interp_call, func, args)
+            except ExecutionFailed as exc:
+                raise BrokenWorkerInterpreter(exc.excinfo) from exc
+
+            if is_exception:
+                raise res
+
+            return res
+elif sys.version_info >= (3, 13):
+    import _interpqueues
+    import _interpreters
+
+    UNBOUND: Final = 2  # I have no clue how this works, but it was used in the stdlib
+    FMT_UNPICKLED: Final = 0
+    FMT_PICKLED: Final = 1
+    QUEUE_PICKLE_ARGS: Final = (FMT_PICKLED, UNBOUND)
+    QUEUE_UNPICKLE_ARGS: Final = (FMT_UNPICKLED, UNBOUND)
+
+    _run_func = compile(
+        """
+import _interpqueues
+from _interpreters import NotShareableError
+from pickle import loads, dumps, HIGHEST_PROTOCOL
+
+QUEUE_PICKLE_ARGS = (1, 2)
+QUEUE_UNPICKLE_ARGS = (0, 2)
+
+item = _interpqueues.get(queue_id)[0]
+try:
+    func, args = loads(item)
+    retval = func(*args)
+except BaseException as exc:
+    is_exception = True
+    retval = exc
+else:
+    is_exception = False
+
+try:
+    _interpqueues.put(queue_id, (retval, is_exception), *QUEUE_UNPICKLE_ARGS)
+except NotShareableError:
+    retval = dumps(retval, HIGHEST_PROTOCOL)
+    _interpqueues.put(queue_id, (retval, is_exception), *QUEUE_PICKLE_ARGS)
+    """,
+        "<string>",
+        "exec",
+    )
+
+    class Worker:
+        last_used: float = 0
+
+        def __init__(self) -> None:
+            self._interpreter_id = _interpreters.create()
+            self._queue_id = _interpqueues.create(1, *QUEUE_UNPICKLE_ARGS)
+            _interpreters.set___main___attrs(
+                self._interpreter_id, {"queue_id": self._queue_id}
+            )
+
+        def destroy(self) -> None:
+            _interpqueues.destroy(self._queue_id)
+            _interpreters.destroy(self._interpreter_id)
+
+        def call(
+            self,
+            func: Callable[..., T_Retval],
+            args: tuple[Any, ...],
+        ) -> T_Retval:
+            import pickle
+
+            item = pickle.dumps((func, args), pickle.HIGHEST_PROTOCOL)
+            _interpqueues.put(self._queue_id, item, *QUEUE_PICKLE_ARGS)
+            exc_info = _interpreters.exec(self._interpreter_id, _run_func)
+            if exc_info:
+                raise BrokenWorkerInterpreter(exc_info)
+
+            res = _interpqueues.get(self._queue_id)
+            (res, is_exception), fmt = res[:2]
+            if fmt == FMT_PICKLED:
+                res = pickle.loads(res)
+
+            if is_exception:
+                raise res
+
+            return res
+else:
+
+    class Worker:
+        last_used: float = 0
+
+        def __init__(self) -> None:
+            raise RuntimeError("subinterpreters require at least Python 3.13")
+
+        def call(
+            self,
+            func: Callable[..., T_Retval],
+            args: tuple[Any, ...],
+        ) -> T_Retval:
+            raise NotImplementedError
+
+        def destroy(self) -> None:
+            pass
+
+
+DEFAULT_CPU_COUNT: Final = 8  # this is just an arbitrarily selected value
+MAX_WORKER_IDLE_TIME = (
+    30  # seconds a subinterpreter can be idle before becoming eligible for pruning
+)
+
+T_Retval = TypeVar("T_Retval")
+PosArgsT = TypeVarTuple("PosArgsT")
+
+_idle_workers = RunVar[deque[Worker]]("_available_workers")
+_default_interpreter_limiter = RunVar[CapacityLimiter]("_default_interpreter_limiter")
+
+
+def _stop_workers(workers: deque[Worker]) -> None:
+    for worker in workers:
+        worker.destroy()
+
+    workers.clear()
+
+
+async def run_sync(
+    func: Callable[[Unpack[PosArgsT]], T_Retval],
+    *args: Unpack[PosArgsT],
+    limiter: CapacityLimiter | None = None,
+) -> T_Retval:
+    """
+    Call the given function with the given arguments in a subinterpreter.
+
+    .. warning:: On Python 3.13, the :mod:`concurrent.interpreters` module was not yet
+        available, so the code path for that Python version relies on an undocumented,
+        private API. As such, it is recommended to not rely on this function for anything
+        mission-critical on Python 3.13.
+
+    :param func: a callable
+    :param args: the positional arguments for the callable
+    :param limiter: capacity limiter to use to limit the total number of subinterpreters
+        running (if omitted, the default limiter is used)
+    :return: the result of the call
+    :raises BrokenWorkerInterpreter: if there's an internal error in a subinterpreter
+
+    """
+    if limiter is None:
+        limiter = current_default_interpreter_limiter()
+
+    try:
+        idle_workers = _idle_workers.get()
+    except LookupError:
+        idle_workers = deque()
+        _idle_workers.set(idle_workers)
+        atexit.register(_stop_workers, idle_workers)
+
+    async with limiter:
+        try:
+            worker = idle_workers.pop()
+        except IndexError:
+            worker = Worker()
+
+    try:
+        return await to_thread.run_sync(
+            worker.call,
+            func,
+            args,
+            limiter=limiter,
+        )
+    finally:
+        # Prune workers that have been idle for too long
+        now = current_time()
+        while idle_workers:
+            if now - idle_workers[0].last_used <= MAX_WORKER_IDLE_TIME:
+                break
+
+            await to_thread.run_sync(idle_workers.popleft().destroy, limiter=limiter)
+
+        worker.last_used = current_time()
+        idle_workers.append(worker)
+
+
+def current_default_interpreter_limiter() -> CapacityLimiter:
+    """
+    Return the capacity limiter used by default to limit the number of concurrently
+    running subinterpreters.
+
+    Defaults to the number of CPU cores.
+
+    :return: a capacity limiter object
+
+    """
+    try:
+        return _default_interpreter_limiter.get()
+    except LookupError:
+        limiter = CapacityLimiter(os.cpu_count() or DEFAULT_CPU_COUNT)
+        _default_interpreter_limiter.set(limiter)
+        return limiter