98 lines
2.7 KiB
Python
98 lines
2.7 KiB
Python
|
from __future__ import annotations
|
||
|
|
||
|
import sys
|
||
|
from abc import ABCMeta, abstractmethod
|
||
|
from collections.abc import Awaitable, Callable
|
||
|
from types import TracebackType
|
||
|
from typing import TYPE_CHECKING, Any, Protocol, TypeVar, overload
|
||
|
|
||
|
if sys.version_info >= (3, 11):
|
||
|
from typing import TypeVarTuple, Unpack
|
||
|
else:
|
||
|
from typing_extensions import TypeVarTuple, Unpack
|
||
|
|
||
|
if TYPE_CHECKING:
|
||
|
from .._core._tasks import CancelScope
|
||
|
|
||
|
T_Retval = TypeVar("T_Retval")
|
||
|
T_contra = TypeVar("T_contra", contravariant=True)
|
||
|
PosArgsT = TypeVarTuple("PosArgsT")
|
||
|
|
||
|
|
||
|
class TaskStatus(Protocol[T_contra]):
|
||
|
@overload
|
||
|
def started(self: TaskStatus[None]) -> None:
|
||
|
...
|
||
|
|
||
|
@overload
|
||
|
def started(self, value: T_contra) -> None:
|
||
|
...
|
||
|
|
||
|
def started(self, value: T_contra | None = None) -> None:
|
||
|
"""
|
||
|
Signal that the task has started.
|
||
|
|
||
|
:param value: object passed back to the starter of the task
|
||
|
"""
|
||
|
|
||
|
|
||
|
class TaskGroup(metaclass=ABCMeta):
|
||
|
"""
|
||
|
Groups several asynchronous tasks together.
|
||
|
|
||
|
:ivar cancel_scope: the cancel scope inherited by all child tasks
|
||
|
:vartype cancel_scope: CancelScope
|
||
|
"""
|
||
|
|
||
|
cancel_scope: CancelScope
|
||
|
|
||
|
@abstractmethod
|
||
|
def start_soon(
|
||
|
self,
|
||
|
func: Callable[[Unpack[PosArgsT]], Awaitable[Any]],
|
||
|
*args: Unpack[PosArgsT],
|
||
|
name: object = None,
|
||
|
) -> None:
|
||
|
"""
|
||
|
Start a new task in this task group.
|
||
|
|
||
|
:param func: a coroutine function
|
||
|
:param args: positional arguments to call the function with
|
||
|
:param name: name of the task, for the purposes of introspection and debugging
|
||
|
|
||
|
.. versionadded:: 3.0
|
||
|
"""
|
||
|
|
||
|
@abstractmethod
|
||
|
async def start(
|
||
|
self,
|
||
|
func: Callable[..., Awaitable[Any]],
|
||
|
*args: object,
|
||
|
name: object = None,
|
||
|
) -> Any:
|
||
|
"""
|
||
|
Start a new task and wait until it signals for readiness.
|
||
|
|
||
|
:param func: a coroutine function
|
||
|
:param args: positional arguments to call the function with
|
||
|
:param name: name of the task, for the purposes of introspection and debugging
|
||
|
:return: the value passed to ``task_status.started()``
|
||
|
:raises RuntimeError: if the task finishes without calling
|
||
|
``task_status.started()``
|
||
|
|
||
|
.. versionadded:: 3.0
|
||
|
"""
|
||
|
|
||
|
@abstractmethod
|
||
|
async def __aenter__(self) -> TaskGroup:
|
||
|
"""Enter the task group context and allow starting new tasks."""
|
||
|
|
||
|
@abstractmethod
|
||
|
async def __aexit__(
|
||
|
self,
|
||
|
exc_type: type[BaseException] | None,
|
||
|
exc_val: BaseException | None,
|
||
|
exc_tb: TracebackType | None,
|
||
|
) -> bool | None:
|
||
|
"""Exit the task group context waiting for all tasks to finish."""
|