|
from __future__ import annotations |
|
|
|
import sys |
|
from abc import ABCMeta, abstractmethod |
|
from types import TracebackType |
|
from typing import TYPE_CHECKING, Any, Awaitable, Callable, TypeVar, overload |
|
from warnings import warn |
|
|
|
if sys.version_info >= (3, 8): |
|
from typing import Protocol |
|
else: |
|
from typing_extensions import Protocol |
|
|
|
if TYPE_CHECKING: |
|
from anyio._core._tasks import CancelScope |
|
|
|
T_Retval = TypeVar("T_Retval") |
|
T_contra = TypeVar("T_contra", contravariant=True) |
|
|
|
|
|
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 |
|
|
|
async def spawn( |
|
self, |
|
func: Callable[..., Awaitable[Any]], |
|
*args: object, |
|
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 |
|
|
|
.. deprecated:: 3.0 |
|
Use :meth:`start_soon` instead. If your code needs AnyIO 2 compatibility, you |
|
can keep using this until AnyIO 4. |
|
|
|
""" |
|
warn( |
|
'spawn() is deprecated -- use start_soon() (without the "await") instead', |
|
DeprecationWarning, |
|
) |
|
self.start_soon(func, *args, name=name) |
|
|
|
@abstractmethod |
|
def start_soon( |
|
self, |
|
func: Callable[..., Awaitable[Any]], |
|
*args: object, |
|
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.""" |
|
|