sorcio / async_exit_stack

AsyncExitStack backport for Python 3.5+

• Free software: PSF license
• Documentation: https://docs.python.org/3.7/library/contextlib.html#contextlib.AsyncExitStack

This package contains code from the CPython project.

Install

pip install async_exit_stack

Usage example

from async_exit_stack import AsyncExitStack

async def some_async_function():
    async with AsyncExitStack() as stack:
        connections = [await stack.enter_async_context(get_connection())
            for i in range(5)]
        # All opened connections will automatically be released at the end of
        # the async with statement, even if attempts to open a connection
        # later in the list raise an exception.

Reference

Refer to Python 3.7 contextlib documentation for a complete reference and more context.

class AsyncExitStack

An asynchronous context manager, similar to ExitStack, that supports combining both synchronous and asynchronous context managers, as well as having coroutines for cleanup logic.

The close() method is not implemented, aclose() must be used instead.

enter_async_context(cm)

Similar to enter_context() but expects an asynchronous context manager.

push_async_exit(exit)

Similar to push() but expects either an asynchronous context manager or a coroutine.

push_async_callback(callback, *args, **kwds)

Similar to callback() but expects a coroutine.

aclose()

Similar to close() but properly handles awaitables.