Consider delegating to nest_asyncio

[t0yv0]

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Issue details

Pulumi Python SDK carries logic in sync_await.py that is non-trivial and seems to overlap with the https://github.com/erdewit/nest_asyncio library. If this makes sense for the project, it could be nice to re-use and delegate to nest_asyncio.

Illustration:

import asyncio

import nest_asyncio
nest_asyncio.apply()


def do_sync(another_task):
    # it is not normally possible to await an aio task inside a def
    # that is not yet async, like this one, when this def is invoked
    # from a task itself. What one gets in standard Python is:
    #
    # raise RuntimeError('This event loop is already running')
    #
    # Pulumi introduecs _sync_await to fix this.
    #
    # The alternative is to enable `nest_asyncio` that makes
    # `run_until_complete` work as expected.
    loop = asyncio.get_event_loop()
    return loop.run_until_complete(another_task)


async def do_io(another_task):
    print('io start')
    await asyncio.sleep(5)
    result = do_sync(another_task)
    print(f'result = {result}')
    print('io end')


async def do_other_things():
    print('doing other things')
    return 'other things'


loop = asyncio.get_event_loop()

f1 = loop.create_task(do_other_things())
f2 = loop.create_task(do_io(f1))

loop.run_until_complete(f1)
loop.run_until_complete(f2)

loop.close()

Affected area/feature

Python