import asyncio
import warnings
from collections import MutableMapping
from functools import partial
from . import hdrs
from .abc import AbstractAccessLogger, AbstractMatchInfo, AbstractRouter
from .frozenlist import FrozenList
from .helpers import AccessLogger
from .log import web_logger
from .signals import Signal
from .web_middlewares import _fix_request_current_app
from .web_request import Request
from .web_response import StreamResponse
from .web_server import Server
from .web_urldispatcher import PrefixedSubAppResource, UrlDispatcher
__all__ = ('Application',)
class Application(MutableMapping):
ATTRS = frozenset([
'logger', '_debug', '_router', '_loop', '_handler_args',
'_middlewares', '_middlewares_handlers', '_run_middlewares',
'_state', '_frozen', '_subapps',
'_on_response_prepare', '_on_startup', '_on_shutdown',
'_on_cleanup', '_client_max_size'])
def __init__(self, *,
logger=web_logger,
router=None,
middlewares=(),
handler_args=None,
client_max_size=1024**2,
loop=None,
debug=...):
if router is None:
router = UrlDispatcher()
assert isinstance(router, AbstractRouter), router
if loop is not None:
warnings.warn("loop argument is deprecated", DeprecationWarning,
stacklevel=2)
self._debug = debug
self._router = router
self._loop = loop
self._handler_args = handler_args
self.logger = logger
self._middlewares = FrozenList(middlewares)
self._middlewares_handlers = None # initialized on freezing
self._run_middlewares = None # initialized on freezing
self._state = {}
self._frozen = False
self._subapps = []
self._on_response_prepare = Signal(self)
self._on_startup = Signal(self)
self._on_shutdown = Signal(self)
self._on_cleanup = Signal(self)
self._client_max_size = client_max_size
def __init_subclass__(cls):
warnings.warn("Inheritance class {} from web.Application "
"is discouraged".format(cls.__name__),
DeprecationWarning,
stacklevel=2)
def __setattr__(self, name, val):
if name not in self.ATTRS:
warnings.warn("Setting custom web.Application.{} attribute "
"is discouraged".format(name),
DeprecationWarning,
stacklevel=2)
super().__setattr__(name, val)
# MutableMapping API
def __eq__(self, other):
return self is other
def __getitem__(self, key):
return self._state[key]
def _check_frozen(self):
if self._frozen:
warnings.warn("Changing state of started or joined "
"application is deprecated",
DeprecationWarning,
stacklevel=3)
def __setitem__(self, key, value):
self._check_frozen()
self._state[key] = value
def __delitem__(self, key):
self._check_frozen()
del self._state[key]
def __len__(self):
return len(self._state)
def __iter__(self):
return iter(self._state)
########
@property
def loop(self):
return self._loop
def _set_loop(self, loop):
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")
self._loop = loop
# set loop debug
if self._debug is ...:
self._debug = loop.get_debug()
# set loop to sub applications
for subapp in self._subapps:
subapp._set_loop(loop)
@property
def frozen(self):
return self._frozen
def freeze(self):
if self._frozen:
return
self._frozen = True
self._middlewares.freeze()
self._router.freeze()
self._on_response_prepare.freeze()
self._on_startup.freeze()
self._on_shutdown.freeze()
self._on_cleanup.freeze()
self._middlewares_handlers = tuple(self._prepare_middleware())
# If current app and any subapp do not have middlewares avoid run all
# of the code footprint that it implies, which have a middleware
# hardcoded per app that sets up the current_app attribute. If no
# middlewares are configured the handler will receive the proper
# current_app without needing all of this code.
self._run_middlewares = True if self.middlewares else False
for subapp in self._subapps:
subapp.freeze()
self._run_middlewares =\
self._run_middlewares or subapp._run_middlewares
@property
def debug(self):
return self._debug
def _reg_subapp_signals(self, subapp):
def reg_handler(signame):
subsig = getattr(subapp, signame)
async def handler(app):
await subsig.send(subapp)
appsig = getattr(self, signame)
appsig.append(handler)
reg_handler('on_startup')
reg_handler('on_shutdown')
reg_handler('on_cleanup')
def add_subapp(self, prefix, subapp):
if self.frozen:
raise RuntimeError(
"Cannot add sub application to frozen application")
if subapp.frozen:
raise RuntimeError("Cannot add frozen application")
if prefix.endswith('/'):
prefix = prefix[:-1]
if prefix in ('', '/'):
raise ValueError("Prefix cannot be empty")
resource = PrefixedSubAppResource(prefix, subapp)
self.router.register_resource(resource)
self._reg_subapp_signals(subapp)
self._subapps.append(subapp)
subapp.freeze()
if self._loop is not None:
subapp._set_loop(self._loop)
return resource
@property
def on_response_prepare(self):
return self._on_response_prepare
@property
def on_startup(self):
return self._on_startup
@property
def on_shutdown(self):
return self._on_shutdown
@property
def on_cleanup(self):
return self._on_cleanup
@property
def router(self):
return self._router
@property
def middlewares(self):
return self._middlewares
def make_handler(self, *,
loop=None,
access_log_class=AccessLogger,
**kwargs):
if not issubclass(access_log_class, AbstractAccessLogger):
raise TypeError(
'access_log_class must be subclass of '
'aiohttp.abc.AbstractAccessLogger, got {}'.format(
access_log_class))
self._set_loop(loop)
self.freeze()
kwargs['debug'] = self.debug
if self._handler_args:
for k, v in self._handler_args.items():
kwargs[k] = v
return Server(self._handle, request_factory=self._make_request,
access_log_class=access_log_class,
loop=self.loop, **kwargs)
async def startup(self):
"""Causes on_startup signal
Should be called in the event loop along with the request handler.
"""
await self.on_startup.send(self)
async def shutdown(self):
"""Causes on_shutdown signal
Should be called before cleanup()
"""
await self.on_shutdown.send(self)
async def cleanup(self):
"""Causes on_cleanup signal
Should be called after shutdown()
"""
await self.on_cleanup.send(self)
def _make_request(self, message, payload, protocol, writer, task,
_cls=Request):
return _cls(
message, payload, protocol, writer, task,
self._loop,
client_max_size=self._client_max_size)
def _prepare_middleware(self):
for m in reversed(self._middlewares):
if getattr(m, '__middleware_version__', None) == 1:
yield m, True
else:
warnings.warn('old-style middleware "{!r}" deprecated, '
'see #2252'.format(m),
DeprecationWarning, stacklevel=2)
yield m, False
yield _fix_request_current_app(self), True
async def _handle(self, request):
match_info = await self._router.resolve(request)
assert isinstance(match_info, AbstractMatchInfo), match_info
match_info.add_app(self)
if __debug__:
match_info.freeze()
resp = None
request._match_info = match_info
expect = request.headers.get(hdrs.EXPECT)
if expect:
resp = await match_info.expect_handler(request)
await request.writer.drain()
if resp is None:
handler = match_info.handler
if self._run_middlewares:
for app in match_info.apps[::-1]:
for m, new_style in app._middlewares_handlers:
if new_style:
handler = partial(m, handler=handler)
else:
handler = await m(app, handler)
resp = await handler(request)
assert isinstance(resp, StreamResponse), \
("Handler {!r} should return response instance, "
"got {!r} [middlewares {!r}]").format(
match_info.handler, type(resp),
[middleware
for app in match_info.apps
for middleware in app.middlewares])
return resp
def __call__(self):
"""gunicorn compatibility"""
return self
def __repr__(self):
return "<Application 0x{:x}>".format(id(self))