tractor/tests/test_resource_cache.py

105 lines
2.9 KiB
Python

'''
Async context manager cache api testing: ``trionics.maybe_open_context():``
'''
from contextlib import asynccontextmanager as acm
from typing import Awaitable
import trio
import tractor
@tractor.context
async def streamer(
ctx: tractor.Context,
seq: list[int] = list(range(1000)),
) -> None:
await ctx.started()
async with ctx.open_stream() as stream:
for val in seq:
await stream.send(val)
await trio.sleep(0.001)
@acm
async def open_stream() -> Awaitable[tractor.MsgStream]:
async with tractor.open_nursery() as tn:
portal = await tn.start_actor('streamer', enable_modules=[__name__])
async with (
portal.open_context(streamer) as (ctx, first),
ctx.open_stream() as stream,
):
yield stream
breakpoint()
print('CANCELLING STREAMER')
await portal.cancel_actor()
@acm
async def maybe_open_stream(taskname: str):
async with tractor.trionics.maybe_open_context(
# NOTE: all secondary tasks should cache hit on the same key
key='stream',
mngr=open_stream(),
) as (cache_hit, stream):
if cache_hit:
print(f'{taskname} loaded from cache')
# add a new broadcast subscription for the quote stream
# if this feed is already allocated by the first
# task that entereed
async with stream.subscribe() as bstream:
yield bstream
else:
# yield the actual stream
yield stream
def test_open_local_sub_to_stream():
'''
Verify a single inter-actor stream can can be fanned-out shared to
N local tasks using ``trionics.maybe_open_context():``.
'''
async def main():
full = list(range(1000))
async def get_sub_and_pull(taskname: str):
async with (
maybe_open_stream(taskname) as stream,
):
if '0' in taskname:
assert isinstance(stream, tractor.MsgStream)
else:
assert isinstance(
stream,
tractor.trionics.BroadcastReceiver
)
first = await stream.receive()
print(f'{taskname} started with value {first}')
seq = []
async for msg in stream:
seq.append(msg)
print(f'{taskname} received {msg}')
assert set(seq).issubset(set(full))
print(f'{taskname} finished')
# TODO: turns out this isn't multi-task entrant XD
# We probably need an indepotent entry semantic?
async with tractor.open_root_actor():
async with (
trio.open_nursery() as nurse,
):
for i in range(10):
nurse.start_soon(get_sub_and_pull, f'task_{i}')
await trio.sleep(0.001)
trio.run(main)