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@lanfon72
Created March 7, 2021 13:54
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import time
import asyncio
import contextvars
from random import random
from threading import current_thread
from concurrent.futures import ThreadPoolExecutor
# declare context var
request_id = contextvars.ContextVar('Id of request.')
def run_in_thread(req_id):
time.sleep(random() * 5)
if request_id.get(None):
print(f"\t\tinput={req_id} \tprev={request_id.get()} in {current_thread().name}")
request_id.set(req_id)
print(f"\t\t{req_id} setted in {current_thread().name}")
return req_id
async def some_inner_coroutine(myid):
# get value
await asyncio.sleep(random() * 5)
prev, curr = myid, request_id.get()
if prev != curr:
print(f"ERROR: {prev} != {curr}")
else:
request_id.set(myid * 10)
return curr
async def some_outer_coroutine(req_id):
# set value
request_id.set(req_id)
fut = asyncio.ensure_future(some_inner_coroutine(req_id))
request_id.set(req_id * 100)
inner_val = await fut
outer_changed = request_id.get()
print(f"{inner_val=} \t{req_id=} \t{outer_changed=}")
return req_id
async def some_outer_with_await(req_id):
request_id.set(req_id)
await some_inner_coroutine(req_id)
inner_changed = request_id.get()
print(f"\t\t\t==> origin {req_id=} \t {inner_changed=}")
async def main():
tasks = []
asyncio.get_running_loop().set_default_executor(ThreadPoolExecutor(2))
print(f"--- globally request_id={request_id.get(None)}")
for req_id in range(1, 30):
if req_id % 3:
tasks.append(asyncio.ensure_future(some_outer_with_await(req_id)))
elif req_id % 6 == 0:
tasks.append(asyncio.get_running_loop().run_in_executor(None, run_in_thread, req_id))
else:
tasks.append(asyncio.ensure_future(some_outer_coroutine(req_id)))
await asyncio.gather(*tasks)
print(f"--- globally request_id={request_id.get(None)}")
asyncio.run(main())
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