Subapps (#1301)

* Change AbstractResource.resolve signature

* Work in progress

* Add a section about subapps

* Work on subapps

* Add a test for reverse URL usage by subapp

* Fix pep8 error

* Fix tests

* Fix docs spelling errors

* Improve test coverage

* Improve coverage

* Better coverage

* Work on coverage

* Add another test

* Another test

* Add another test

* Support nested subapp middlewares

* Support signals in subapplication

aiohttp/abc.py

@@ -35,6 +35,29 @@ def http_exception(self):
     def get_info(self):
         """Return a dict with additional info useful for introspection"""
 
+    @property  # pragma: no branch
+    @abstractmethod
+    def apps(self):
+        """Stack of nested applications.
+
+        Top level application is left-most element.
+
+        """
+
+    @abstractmethod
+    def add_app(self, app):
+        """Add application to the nested apps stack."""
+
+    @abstractmethod
+    def freeze(self):
+        """Freeze the match info.
+
+        The method is called after route resolution.
+
+        After the call .add_app() is forbidden.
+
+        """
+
 
 class AbstractView(ABC):
 

aiohttp/test_utils.py

@@ -19,7 +19,7 @@
 from .helpers import sentinel
 from .protocol import HttpVersion, RawRequestMessage
 from .signals import Signal
-from .web import Application, Request
+from .web import Application, Request, UrlMappingMatchInfo
 
 PY_35 = sys.version_info >= (3, 5)
 
@@ -66,6 +66,7 @@ def start_server(self, **kwargs):
         self._root = URL('{}://{}:{}'.format(self.scheme,
                                              self.host,
                                              self.port))
+        yield from self.app.startup()
         self.handler = self.app.make_handler(**kwargs)
         self.server = yield from self._loop.create_server(self.handler,
                                                           self.host,
@@ -502,10 +503,14 @@ def make_mocked_request(method, path, headers=None, *,
     if payload is sentinel:
         payload = mock.Mock()
 
-    req = Request(app, message, payload,
+    req = Request(message, payload,
                   transport, reader, writer,
                   secure_proxy_ssl_header=secure_proxy_ssl_header)
 
+    match_info = UrlMappingMatchInfo({}, mock.Mock())
+    match_info.add_app(app)
+    req._match_info = match_info
+
     return req
 
 

aiohttp/web.py

@@ -39,7 +39,6 @@ def __init__(self, manager, app, router, *,
         self._manager = manager
         self._app = app
         self._router = router
-        self._middlewares = app.middlewares
         self._secure_proxy_ssl_header = secure_proxy_ssl_header
 
     def __repr__(self):
@@ -65,15 +64,16 @@ def handle_request(self, message, payload):
 
         app = self._app
         request = web_reqrep.Request(
-            app, message, payload,
+            message, payload,
             self.transport, self.reader, self.writer,
             secure_proxy_ssl_header=self._secure_proxy_ssl_header)
         self._meth = request.method
         self._path = request.path
         try:
             match_info = yield from self._router.resolve(request)
-
             assert isinstance(match_info, AbstractMatchInfo), match_info
+            match_info.add_app(app)
+            match_info.freeze()
 
             resp = None
             request._match_info = match_info
@@ -84,7 +84,7 @@ def handle_request(self, message, payload):
 
             if resp is None:
                 handler = match_info.handler
-                for factory in reversed(self._middlewares):
+                for factory in match_info.middlewares:
                     handler = yield from factory(app, handler)
                 resp = yield from handler(request)
 
@@ -166,7 +166,7 @@ def __init__(self, *, logger=web_logger, loop=None,
         if loop is None:
             loop = asyncio.get_event_loop()
         if router is None:
-            router = web_urldispatcher.UrlDispatcher()
+            router = web_urldispatcher.UrlDispatcher(self)
         assert isinstance(router, AbstractRouter), router
 
         self._debug = debug
@@ -188,6 +188,13 @@ def __init__(self, *, logger=web_logger, loop=None,
     def debug(self):
         return self._debug
 
+    def _reg_subapp_signals(self, subapp):
+        self._on_pre_signal.extend(subapp.on_pre_signal)
+        self._on_post_signal.extend(subapp.on_post_signal)
+        self._on_startup.extend(subapp.on_startup)
+        self._on_shutdown.extend(subapp.on_shutdown)
+        self._on_cleanup.extend(subapp.on_cleanup)
+
     @property
     def on_response_prepare(self):
         return self._on_response_prepare
@@ -288,7 +295,7 @@ def __call__(self):
         return self
 
     def __repr__(self):
-        return "<Application>"
+        return "<Application 0x{:x}>".format(id(self))
 
 
 def run_app(app, *, host='0.0.0.0', port=None,

aiohttp/web_reqrep.py

@@ -91,9 +91,9 @@ class Request(dict, HeadersMixin):
     POST_METHODS = {hdrs.METH_PATCH, hdrs.METH_POST, hdrs.METH_PUT,
                     hdrs.METH_TRACE, hdrs.METH_DELETE}
 
-    def __init__(self, app, message, payload, transport, reader, writer, *,
+    def __init__(self, message, payload, transport, reader, writer, *,
                  secure_proxy_ssl_header=None):
-        self._app = app
+        self._app = None
         self._message = message
         self._transport = transport
         self._reader = reader
@@ -274,10 +274,10 @@ def match_info(self):
         """Result of route resolving."""
         return self._match_info
 
-    @property
+    @reify
     def app(self):
         """Application instance."""
-        return self._app
+        return self._match_info.apps[-1]
 
     @property
     def transport(self):
@@ -724,7 +724,8 @@ def prepare(self, request):
         resp_impl = self._start_pre_check(request)
         if resp_impl is not None:
             return resp_impl
-        yield from request.app.on_response_prepare.send(request, self)
+        for app in request.match_info.apps:
+            yield from app.on_response_prepare.send(request, self)
 
         return self._start(request)