1# Copyright 2019 The gRPC Authors 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# http://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14 15import logging 16import functools 17import asyncio 18from typing import Callable 19import unittest 20from grpc.experimental import aio 21 22__all__ = 'AioTestBase' 23 24_COROUTINE_FUNCTION_ALLOWLIST = ['setUp', 'tearDown'] 25 26 27def _async_to_sync_decorator(f: Callable, loop: asyncio.AbstractEventLoop): 28 29 @functools.wraps(f) 30 def wrapper(*args, **kwargs): 31 return loop.run_until_complete(f(*args, **kwargs)) 32 33 return wrapper 34 35 36def _get_default_loop(debug=True): 37 try: 38 loop = asyncio.get_event_loop() 39 except: 40 loop = asyncio.new_event_loop() 41 asyncio.set_event_loop(loop) 42 finally: 43 loop.set_debug(debug) 44 return loop 45 46 47# NOTE(gnossen) this test class can also be implemented with metaclass. 48class AioTestBase(unittest.TestCase): 49 # NOTE(lidi) We need to pick a loop for entire testing phase, otherwise it 50 # will trigger create new loops in new threads, leads to deadlock. 51 _TEST_LOOP = _get_default_loop() 52 53 @property 54 def loop(self): 55 return self._TEST_LOOP 56 57 def __getattribute__(self, name): 58 """Overrides the loading logic to support coroutine functions.""" 59 attr = super().__getattribute__(name) 60 61 # If possible, converts the coroutine into a sync function. 62 if name.startswith('test_') or name in _COROUTINE_FUNCTION_ALLOWLIST: 63 if asyncio.iscoroutinefunction(attr): 64 return _async_to_sync_decorator(attr, self._TEST_LOOP) 65 # For other attributes, let them pass. 66 return attr 67