Encourage creation of aiohttp public objects inside a coroutine

CHANGES/3333.removal

@@ -0,0 +1 @@
+Replace asyncio.get_event_loop() with get_running_loop() for encourage creation of aiohttp public objects inside a coroutine

CONTRIBUTORS.txt

@@ -230,6 +230,7 @@ Yannick Péroux
 Ye Cao
 Yegor Roganov
 Young-Ho Cha
+Yunhao Zhang
 Yuriy Shatrov
 Yury Selivanov
 Yusuke Tsutsumi

aiohttp/base_protocol.py

@@ -1,6 +1,7 @@
 import asyncio
 from typing import Optional, cast
 
+from .helpers import get_running_loop
 from .log import internal_logger
 
 
@@ -10,7 +11,7 @@ class BaseProtocol(asyncio.Protocol):
 
     def __init__(self, loop: Optional[asyncio.AbstractEventLoop]=None) -> None:
         if loop is None:
-            self._loop = asyncio.get_event_loop()
+            self._loop = get_running_loop()
         else:
             self._loop = loop
         self._paused = False

aiohttp/client.py

@@ -29,7 +29,8 @@
 from .connector import BaseConnector, TCPConnector
 from .cookiejar import CookieJar
 from .helpers import (DEBUG, PY_36, CeilTimeout, TimeoutHandle,
-                      proxies_from_env, sentinel, strip_auth_from_url)
+                      get_running_loop, proxies_from_env, sentinel,
+                      strip_auth_from_url)
 from .http import WS_KEY, WebSocketReader, WebSocketWriter
 from .http_websocket import WSHandshakeError, ws_ext_gen, ws_ext_parse
 from .streams import FlowControlDataQueue
@@ -107,7 +108,7 @@ def __init__(self, *, connector=None, loop=None, cookies=None,
                 loop = connector._loop
             else:
                 implicit_loop = True
-                loop = asyncio.get_event_loop()
+                loop = get_running_loop()
 
         if connector is None:
             connector = TCPConnector(loop=loop)

aiohttp/client_reqrep.py

@@ -19,7 +19,8 @@
                                 ClientResponseError, ContentTypeError,
                                 InvalidURL, ServerFingerprintMismatch)
 from .formdata import FormData
-from .helpers import PY_36, HeadersMixin, TimerNoop, noop, reify, set_result
+from .helpers import (PY_36, HeadersMixin, TimerNoop, get_running_loop, noop,
+                      reify, set_result)
 from .http import SERVER_SOFTWARE, HttpVersion10, HttpVersion11, StreamWriter
 from .log import client_logger
 from .streams import StreamReader  # noqa
@@ -197,7 +198,7 @@ def __init__(self, method, url, *,
                  traces=None):
 
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
 
         assert isinstance(url, URL), url
         assert isinstance(proxy, (URL, type(None))), proxy

aiohttp/connector.py

@@ -22,7 +22,8 @@
                                 ssl_errors)
 from .client_proto import ResponseHandler
 from .client_reqrep import ClientRequest, Fingerprint, _merge_ssl_params
-from .helpers import PY_36, CeilTimeout, is_ip_address, noop, sentinel
+from .helpers import (PY_36, CeilTimeout, get_running_loop, is_ip_address,
+                      noop, sentinel)
 from .locks import EventResultOrError
 from .resolver import DefaultResolver
 
@@ -171,7 +172,7 @@ def __init__(self, *, keepalive_timeout=sentinel,
                 keepalive_timeout = 15.0
 
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
 
         self._closed = False
         if loop.get_debug():

aiohttp/helpers.py

@@ -13,6 +13,7 @@
 import re
 import sys
 import time
+import warnings
 import weakref
 from collections import namedtuple
 from contextlib import suppress
@@ -230,6 +231,15 @@ def current_task(loop: Optional[asyncio.AbstractEventLoop]=None) -> asyncio.Task
         return asyncio.Task.current_task(loop=loop)  # type: ignore
 
 
+def get_running_loop(loop: Optional[asyncio.AbstractEventLoop]=None) -> asyncio.AbstractEventLoop:  # type: ignore  # noqa
+    if loop is None:
+        loop = asyncio.get_event_loop()
+    if not loop.is_running():
+        warnings.warn("The object should be created from async function",
+                      DeprecationWarning, stacklevel=3)
+    return loop
+
+
 def isasyncgenfunction(obj: Any) -> bool:
     func = getattr(inspect, 'isasyncgenfunction', None)
     if func is not None:

aiohttp/resolver.py

@@ -3,6 +3,7 @@
 from typing import Any, Dict, List, Optional
 
 from .abc import AbstractResolver
+from .helpers import get_running_loop
 
 
 __all__ = ('ThreadedResolver', 'AsyncResolver', 'DefaultResolver')
@@ -23,7 +24,7 @@ class ThreadedResolver(AbstractResolver):
 
     def __init__(self, loop: Optional[asyncio.AbstractEventLoop]=None) -> None:
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
         self._loop = loop
 
     async def resolve(self, host: str, port: int=0,
@@ -51,7 +52,7 @@ class AsyncResolver(AbstractResolver):
     def __init__(self, loop: Optional[asyncio.AbstractEventLoop]=None,
                  *args: Any, **kwargs: Any) -> None:
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
 
         if aiodns is None:
             raise RuntimeError("Resolver requires aiodns library")

aiohttp/streams.py

@@ -4,7 +4,8 @@
 from typing import Awaitable, Callable, Optional, Tuple
 
 from .base_protocol import BaseProtocol
-from .helpers import BaseTimerContext, set_exception, set_result
+from .helpers import (BaseTimerContext, get_running_loop, set_exception,
+                      set_result)
 from .log import internal_logger
 
 
@@ -112,7 +113,7 @@ def __init__(self, protocol: BaseProtocol,
         self._low_water = limit
         self._high_water = limit * 2
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
         self._loop = loop
         self._size = 0
         self._cursor = 0

aiohttp/web_app.py

@@ -9,7 +9,7 @@
 from . import hdrs
 from .abc import AbstractAccessLogger, AbstractMatchInfo, AbstractRouter
 from .frozenlist import FrozenList
-from .helpers import DEBUG, AccessLogger
+from .helpers import DEBUG, AccessLogger, get_running_loop
 from .log import web_logger
 from .signals import Signal
 from .web_middlewares import _fix_request_current_app
@@ -151,7 +151,7 @@ def loop(self):
 
     def _set_loop(self, loop):
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
         if self._loop is not None and self._loop is not loop:
             raise RuntimeError(
                 "web.Application instance initialized with different loop")

aiohttp/web_runner.py

@@ -1,10 +1,10 @@
-import asyncio
 import signal
 import socket
 from abc import ABC, abstractmethod
 
 from yarl import URL
 
+from .helpers import get_running_loop
 from .web_app import Application
 
 
@@ -81,7 +81,7 @@ def name(self):
 
     async def start(self):
         await super().start()
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
         self._server = await loop.create_server(
             self._runner.server, self._host, self._port,
             ssl=self._ssl_context, backlog=self._backlog,
@@ -106,7 +106,7 @@ def name(self):
 
     async def start(self):
         await super().start()
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
         self._server = await loop.create_unix_server(
             self._runner.server, self._path,
             ssl=self._ssl_context, backlog=self._backlog)
@@ -135,7 +135,7 @@ def name(self):
 
     async def start(self):
         await super().start()
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
         self._server = await loop.create_server(
             self._runner.server, sock=self._sock,
             ssl=self._ssl_context, backlog=self._backlog)
@@ -165,7 +165,7 @@ def sites(self):
         return set(self._sites)
 
     async def setup(self):
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
 
         if self._handle_signals:
             try:
@@ -182,7 +182,7 @@ async def shutdown(self):
         pass  # pragma: no cover
 
     async def cleanup(self):
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
 
         if self._server is None:
             # no started yet, do nothing
@@ -269,7 +269,7 @@ async def shutdown(self):
         await self._app.shutdown()
 
     async def _make_server(self):
-        loop = asyncio.get_event_loop()
+        loop = get_running_loop()
         self._app._set_loop(loop)
         self._app.on_startup.freeze()
         await self._app.startup()

aiohttp/web_server.py

@@ -1,6 +1,7 @@
 """Low level HTTP server."""
 import asyncio
 
+from .helpers import get_running_loop
 from .web_protocol import RequestHandler
 from .web_request import BaseRequest
 
@@ -12,7 +13,7 @@ class Server:
 
     def __init__(self, handler, *, request_factory=None, loop=None, **kwargs):
         if loop is None:
-            loop = asyncio.get_event_loop()
+            loop = get_running_loop()
         self._loop = loop
         self._connections = {}
         self._kwargs = kwargs

aiohttp/worker.py

@@ -12,7 +12,7 @@
 
 from aiohttp import web
 
-from .helpers import AccessLogger, set_result
+from .helpers import AccessLogger, get_running_loop, set_result
 
 
 try:
@@ -41,7 +41,7 @@ def __init__(self, *args, **kw):  # pragma: no cover
 
     def init_process(self):
         # create new event_loop after fork
-        asyncio.get_event_loop().close()
+        get_running_loop().close()
 
         self.loop = asyncio.new_event_loop()
         asyncio.set_event_loop(self.loop)
@@ -198,10 +198,10 @@ def init_process(self):
 
         # Close any existing event loop before setting a
         # new policy.
-        asyncio.get_event_loop().close()
+        get_running_loop().close()
 
         # Setup uvloop policy, so that every
-        # asyncio.get_event_loop() will create an instance
+        # get_running_loop() will create an instance
         # of uvloop event loop.
         asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())
 
@@ -215,10 +215,10 @@ def init_process(self):  # pragma: no cover
 
         # Close any existing event loop before setting a
         # new policy.
-        asyncio.get_event_loop().close()
+        get_running_loop().close()
 
         # Setup tokio policy, so that every
-        # asyncio.get_event_loop() will create an instance
+        # get_running_loop() will create an instance
         # of tokio event loop.
         asyncio.set_event_loop_policy(tokio.EventLoopPolicy())
 

tests/test_client_request.py

@@ -269,8 +269,12 @@ def test_host_header_ipv6_with_port(make_request) -> None:
 
 def test_default_loop(loop) -> None:
     asyncio.set_event_loop(loop)
-    req = ClientRequest('get', URL('http://python.org/'))
-    assert req.loop is loop
+    with pytest.warns(DeprecationWarning) as warning_checker:
+        req = ClientRequest('get', URL('http://python.org/'))
+        assert req.loop is loop
+    assert len(warning_checker) == 1
+    msg = str(warning_checker.list[0].message)
+    assert msg == "The object should be created from async function"
 
 
 def test_default_headers_useragent(make_request) -> None:

tests/test_connector.py

@@ -238,10 +238,14 @@ def test_context_manager(loop) -> None:
 
 def test_ctor_loop() -> None:
     with mock.patch('aiohttp.connector.asyncio') as m_asyncio:
-        session = aiohttp.BaseConnector()
-
+        with pytest.warns(DeprecationWarning) as warning_checker:
+            session = aiohttp.BaseConnector()
     assert session._loop is m_asyncio.get_event_loop.return_value
 
+    assert len(warning_checker) == 1
+    msg = str(warning_checker.list[0].message)
+    assert msg == "The object should be created from async function"
+
 
 def test_close(loop) -> None:
     proto = mock.Mock()
@@ -1363,9 +1367,13 @@ def test_close_cancels_cleanup_closed_handle(loop) -> None:
 def test_ctor_with_default_loop() -> None:
     loop = asyncio.new_event_loop()
     asyncio.set_event_loop(loop)
-    conn = aiohttp.BaseConnector()
-    assert loop is conn._loop
-    loop.close()
+    with pytest.warns(DeprecationWarning) as warning_checker:
+        conn = aiohttp.BaseConnector()
+        assert loop is conn._loop
+        loop.close()
+    assert len(warning_checker) == 1
+    msg = str(warning_checker.list[0].message)
+    assert msg == "The object should be created from async function"
 
 
 async def test_connect_with_limit(loop, key) -> None:

tests/test_resolver.py

@@ -168,8 +168,12 @@ async def test_close_for_async_resolver(loop) -> None:
 
 def test_default_loop_for_threaded_resolver(loop) -> None:
     asyncio.set_event_loop(loop)
-    resolver = ThreadedResolver()
-    assert resolver._loop is loop
+    with pytest.warns(DeprecationWarning) as warning_checker:
+        resolver = ThreadedResolver()
+        assert resolver._loop is loop
+    assert len(warning_checker) == 1
+    msg = str(warning_checker.list[0].message)
+    assert msg == "The object should be created from async function"
 
 
 @pytest.mark.skipif(aiodns is None, reason="aiodns required")

tests/test_streams.py

@@ -49,9 +49,12 @@ async def test_create_waiter(self) -> None:
     def test_ctor_global_loop(self) -> None:
         loop = asyncio.new_event_loop()
         asyncio.set_event_loop(loop)
-        stream = streams.StreamReader(mock.Mock(_reading_paused=False))
-
-        assert stream._loop is loop
+        with pytest.warns(DeprecationWarning) as warning_checker:
+            stream = streams.StreamReader(mock.Mock(_reading_paused=False))
+            assert stream._loop is loop
+        assert len(warning_checker) == 1
+        msg = str(warning_checker.list[0].message)
+        assert msg == "The object should be created from async function"
 
     async def test_at_eof(self) -> None:
         stream = self._make_one()