import asyncio
import contextvars
import logging
import sys

request_id = contextvars.ContextVar("request_id", default=None)


class RequestIdFilter(logging.Filter):
    def filter(self, record):
        record.request_id = request_id.get()
        return True


class NoTracebackFormatter(logging.Formatter):
    def formatException(self, exc_info):
        return ""


handler = logging.StreamHandler(sys.stdout)
handler.addFilter(RequestIdFilter())
handler.setFormatter(NoTracebackFormatter("  logged with request_id=%(request_id)s"))
logging.getLogger("asyncio").addHandler(handler)
logging.getLogger("asyncio").propagate = False


async def fail():
    request_id.set("req-1")
    raise ValueError


async def other_request():
    request_id.set("req-2")
    task = asyncio.ensure_future(fail())
    await asyncio.sleep(0.01)
    del task  # "Task exception was never retrieved" is reported here


async def main(custom_handler):
    if custom_handler:
        asyncio.get_running_loop().set_exception_handler(
            lambda loop, context: loop.default_exception_handler(context)
        )
    await asyncio.create_task(other_request())


print(sys.version)
print("default handler (expected req-1):")
asyncio.run(main(custom_handler=False))
print("custom handler calling default_exception_handler (expected req-1):")
asyncio.run(main(custom_handler=True))

default handler (expected req-1):
  logged with request_id=req-2
custom handler calling default_exception_handler (expected req-1):
  logged with request_id=req-1