sanic/sanic/server/loop.py

67 lines
2.4 KiB
Python

import asyncio
import sys
from os import getenv
from sanic.compat import OS_IS_WINDOWS
from sanic.log import error_logger
from sanic.utils import str_to_bool
def try_use_uvloop() -> None:
"""
Use uvloop instead of the default asyncio loop.
"""
if OS_IS_WINDOWS:
error_logger.warning(
"You are trying to use uvloop, but uvloop is not compatible "
"with your system. You can disable uvloop completely by setting "
"the 'USE_UVLOOP' configuration value to false, or simply not "
"defining it and letting Sanic handle it for you. Sanic will now "
"continue to run using the default event loop."
)
return
try:
import uvloop # type: ignore
except ImportError:
error_logger.warning(
"You are trying to use uvloop, but uvloop is not "
"installed in your system. In order to use uvloop "
"you must first install it. Otherwise, you can disable "
"uvloop completely by setting the 'USE_UVLOOP' "
"configuration value to false. Sanic will now continue "
"to run with the default event loop."
)
return
uvloop_install_removed = str_to_bool(getenv("SANIC_NO_UVLOOP", "no"))
if uvloop_install_removed:
error_logger.info(
"You are requesting to run Sanic using uvloop, but the "
"install-time 'SANIC_NO_UVLOOP' environment variable (used to "
"opt-out of installing uvloop with Sanic) is set to true. If "
"you want to prevent Sanic from overriding the event loop policy "
"during runtime, set the 'USE_UVLOOP' configuration value to "
"false."
)
if not isinstance(asyncio.get_event_loop_policy(), uvloop.EventLoopPolicy):
asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())
def try_windows_loop():
if not OS_IS_WINDOWS:
error_logger.warning(
"You are trying to use an event loop policy that is not "
"compatible with your system. You can simply let Sanic handle "
"selecting the best loop for you. Sanic will now continue to run "
"using the default event loop."
)
return
if sys.version_info >= (3, 8) and not isinstance(
asyncio.get_event_loop_policy(), asyncio.WindowsSelectorEventLoopPolicy
):
asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())