initialize application with loop during freeze process

aiohttp/web.py

@@ -46,14 +46,12 @@ class Application(MutableMapping):
     def __init__(self, *, logger=web_logger, router=None, middlewares=(),
                  handler_args=None, client_max_size=1024**2,
                  loop=None, debug=...):
-        if loop is None:
-            loop = asyncio.get_event_loop()
         if router is None:
             router = web_urldispatcher.UrlDispatcher()
         assert isinstance(router, AbstractRouter), router
 
-        if debug is ...:
-            debug = loop.get_debug()
+        if loop is not None:
+            warnings.warn("loop argument is deprecated", ResourceWarning)
 
         self._debug = debug
         self._router = router
@@ -65,6 +63,7 @@ def __init__(self, *, logger=web_logger, router=None, middlewares=(),
         self._middlewares = FrozenList(middlewares)
         self._state = {}
         self._frozen = False
+        self._subapps = []
 
         self._on_pre_signal = PreSignal()
         self._on_post_signal = PostSignal()
@@ -106,9 +105,19 @@ def __iter__(self):
     def frozen(self):
         return self._frozen
 
-    def freeze(self):
+    def freeze(self, loop=None):
+        if loop is None:
+            loop = asyncio.get_event_loop()
+        if self._loop is not None and self._loop is not loop:
+            raise RuntimeError(
+                "web.Application instance initialized with different loop")
         if self._frozen:
             return
+
+        if self._debug is ...:
+            self._debug = loop.get_debug()
+
+        self._loop = loop
         self._frozen = True
         self._middlewares = tuple(reversed(self._middlewares))
         self._router.freeze()
@@ -119,6 +128,9 @@ def freeze(self):
         self._on_shutdown.freeze()
         self._on_cleanup.freeze()
 
+        for subapp in self._subapps:
+            subapp.freeze(loop=loop)
+
     @property
     def debug(self):
         return self._debug
@@ -152,7 +164,7 @@ def add_subapp(self, prefix, subapp):
         resource = PrefixedSubAppResource(prefix, subapp)
         self.router.register_resource(resource)
         self._reg_subapp_signals(subapp)
-        subapp.freeze()
+        self._subapps.append(subapp)
         return resource
 
     @property
@@ -191,8 +203,9 @@ def loop(self):
     def middlewares(self):
         return self._middlewares
 
-    def make_handler(self, *, secure_proxy_ssl_header=None, **kwargs):
-        self.freeze()
+    def make_handler(self, *, loop=None,
+                     secure_proxy_ssl_header=None, **kwargs):
+        self.freeze(loop=loop)
 
         kwargs['debug'] = self.debug
         if self._handler_args:
@@ -277,14 +290,15 @@ def __repr__(self):
 def run_app(app, *, host=None, port=None, path=None, sock=None,
             shutdown_timeout=60.0, ssl_context=None,
             print=print, backlog=128, access_log_format=None,
-            access_log=access_logger):
+            access_log=access_logger, loop=None):
     """Run an app locally"""
-    loop = app.loop
+    if loop is None:
+        loop = asyncio.get_event_loop()
 
     make_handler_kwargs = dict()
     if access_log_format is not None:
         make_handler_kwargs['access_log_format'] = access_log_format
-    handler = app.make_handler(access_log=access_log,
+    handler = app.make_handler(loop=loop, access_log=access_log,
                                **make_handler_kwargs)
 
     loop.run_until_complete(app.startup())

aiohttp/worker.py

@@ -53,6 +53,7 @@ def make_handler(self, app):
         if hasattr(self.wsgi, 'make_handler'):
             access_log = self.log.access_log if self.cfg.accesslog else None
             return app.make_handler(
+                loop=self.loop,
                 logger=self.log,
                 slow_request_timeout=self.cfg.timeout,
                 keepalive_timeout=self.cfg.keepalive,

docs/migration.rst

@@ -155,6 +155,17 @@ ServerHttpProtocol is dropped, implementation is merged with RequestHandler
 a lot of low-level api's are dropped.
 
 
+Application
+^^^^^^^^^^^
+
+1. Constructor parameter `loop` is deprecated. Loop is get configured by application runner,
+`run_app` function for any of gunicorn workers.
+
+2. `Application.router.add_subapp` is dropped, use `Application.add_subapp` instead
+
+3. `Application.finished` is dropped, use `Application.cleanup` instead
+
+
 WebRequest and WebResponse
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -171,10 +182,6 @@ WebRequest and WebResponse
      async def handle(request):
          return web.FileResponse('path-to-file.txt)
 
-5. `Application.router.add_subapp` is dropped, use `Application.add_subapp` instead
-
-6. `Application.finished` is dropped, use `Application.cleanup` instead
-
 
 RequestPayloadError
 ^^^^^^^^^^^^^^^^^^^

docs/web_reference.rst

@@ -1109,7 +1109,7 @@ will be called during application finishing.
 properties for later access from a :ref:`handler<aiohttp-web-handler>` via the
 :attr:`Request.app` property::
 
-   app = Application(loop=loop)
+   app = Application()
    app['database'] = await aiopg.create_engine(**db_config)
 
    async def handler(request):
@@ -1119,18 +1119,11 @@ properties for later access from a :ref:`handler<aiohttp-web-handler>` via the
 Although :class:`Application` is a :obj:`dict`-like object, it can't be
 duplicated like one using :meth:`Application.copy`.
 
-.. class:: Application(*, loop=None, router=None, logger=<default>, \
+.. class:: Application(*, router=None, logger=<default>, \
                        middlewares=(), debug=False, **kwargs)
 
    The class inherits :class:`dict`.
 
-   :param loop: :ref:`event loop<asyncio-event-loop>` used
-    for processing HTTP requests.
-
-    If param is ``None`` :func:`asyncio.get_event_loop`
-    used for getting default event loop, but we strongly
-    recommend to use explicit loops everywhere.
-
    :param router: :class:`aiohttp.abc.AbstractRouter` instance, the system
                   creates :class:`UrlDispatcher` by default if
                   *router* is ``None``.
@@ -1144,6 +1137,8 @@ duplicated like one using :meth:`Application.copy`.
 
    :param debug: Switches debug mode.
 
+   :param loop: loop parameter is deprecated. loop is get set during freeze stage.
+
    .. attribute:: router
 
       Read-only property that returns *router instance*.
@@ -1222,10 +1217,16 @@ duplicated like one using :meth:`Application.copy`.
 
       .. seealso:: :ref:`aiohttp-web-graceful-shutdown` and :attr:`on_shutdown`.
 
-   .. method:: make_handler(**kwargs)
+   .. method:: make_handler(loop=None, **kwargs)
 
     Creates HTTP protocol factory for handling requests.
 
+    :param loop: :ref:`event loop<asyncio-event-loop>` used
+                 for processing HTTP requests.
+
+                 If param is ``None`` :func:`asyncio.get_event_loop`
+                 used for getting default event loop.
+
     :param tuple secure_proxy_ssl_header: Secure proxy SSL header. Can
       be used to detect request scheme,
       e.g. ``secure_proxy_ssl_header=('X-Forwarded-Proto', 'https')``.
@@ -1264,7 +1265,6 @@ duplicated like one using :meth:`Application.copy`.
     :param float lingering_timeout: maximum waiting time for more
         client data to arrive when lingering close is in effect
 
-
     You should pass result of the method as *protocol_factory* to
     :meth:`~asyncio.AbstractEventLoop.create_server`, e.g.::