import asyncio
import logging
import warnings
from functools import partial, update_wrapper
from typing import (
TYPE_CHECKING,
Any,
AsyncIterator,
Awaitable,
Callable,
Dict,
Iterable,
Iterator,
List,
Mapping,
MutableMapping,
Optional,
Sequence,
Tuple,
Type,
Union,
cast,
)
from aiosignal import Signal
from frozenlist import FrozenList
from . import hdrs
from .abc import (
AbstractAccessLogger,
AbstractMatchInfo,
AbstractRouter,
AbstractStreamWriter,
)
from .helpers import DEBUG
from .http_parser import RawRequestMessage
from .log import web_logger
from .streams import StreamReader
from .web_log import AccessLogger
from .web_middlewares import _fix_request_current_app
from .web_protocol import RequestHandler
from .web_request import Request
from .web_response import StreamResponse
from .web_routedef import AbstractRouteDef
from .web_server import Server
from .web_urldispatcher import (
AbstractResource,
AbstractRoute,
Domain,
MaskDomain,
MatchedSubAppResource,
PrefixedSubAppResource,
UrlDispatcher,
)
__all__ = ("Application", "CleanupError")
if TYPE_CHECKING: # pragma: no cover
from .typedefs import Handler
_AppSignal = Signal[Callable[["Application"], Awaitable[None]]]
_RespPrepareSignal = Signal[Callable[[Request, StreamResponse], Awaitable[None]]]
_Middleware = Union[
Callable[[Request, Handler], Awaitable[StreamResponse]],
Callable[["Application", Handler], Awaitable[Handler]], # old-style
]
_Middlewares = FrozenList[_Middleware]
_MiddlewaresHandlers = Optional[Sequence[Tuple[_Middleware, bool]]]
_Subapps = List["Application"]
else:
# No type checker mode, skip types
_AppSignal = Signal
_RespPrepareSignal = Signal
_Middleware = Callable
_Middlewares = FrozenList
_MiddlewaresHandlers = Optional[Sequence]
_Subapps = List
class Application(MutableMapping[str, Any]):
ATTRS = frozenset(
[
"logger",
"_debug",
"_router",
"_loop",
"_handler_args",
"_middlewares",
"_middlewares_handlers",
"_run_middlewares",
"_state",
"_frozen",
"_pre_frozen",
"_subapps",
"_on_response_prepare",
"_on_startup",
"_on_shutdown",
"_on_cleanup",
"_client_max_size",
"_cleanup_ctx",
]
)
def __init__(
self,
*,
logger: logging.Logger = web_logger,
router: Optional[UrlDispatcher] = None,
middlewares: Iterable[_Middleware] = (),
handler_args: Optional[Mapping[str, Any]] = None,
client_max_size: int = 1024**2,
loop: Optional[asyncio.AbstractEventLoop] = None,
debug: Any = ..., # mypy doesn't support ellipsis
) -> None:
if router is None:
router = UrlDispatcher()
else:
warnings.warn(
"router argument is deprecated", DeprecationWarning, stacklevel=2
)
assert isinstance(router, AbstractRouter), router
if loop is not None:
warnings.warn(
"loop argument is deprecated", DeprecationWarning, stacklevel=2
)
if debug is not ...:
warnings.warn(
"debug argument is deprecated", DeprecationWarning, stacklevel=2
)
self._debug = debug
self._router: UrlDispatcher = router
self._loop = loop
self._handler_args = handler_args
self.logger = logger
self._middlewares: _Middlewares = FrozenList(middlewares)
# initialized on freezing
self._middlewares_handlers: _MiddlewaresHandlers = None
# initialized on freezing
self._run_middlewares: Optional[bool] = None
self._state: Dict[str, Any] = {}
self._frozen = False
self._pre_frozen = False
self._subapps: _Subapps = []
self._on_response_prepare: _RespPrepareSignal = Signal(self)
self._on_startup: _AppSignal = Signal(self)
self._on_shutdown: _AppSignal = Signal(self)
self._on_cleanup: _AppSignal = Signal(self)
self._cleanup_ctx = CleanupContext()
self._on_startup.append(self._cleanup_ctx._on_startup)
self._on_cleanup.append(self._cleanup_ctx._on_cleanup)
self._client_max_size = client_max_size
def __init_subclass__(cls: Type["Application"]) -> None:
warnings.warn(
"Inheritance class {} from web.Application "
"is discouraged".format(cls.__name__),
DeprecationWarning,
stacklevel=2,
)
if DEBUG: # pragma: no cover
def __setattr__(self, name: str, val: Any) -> None:
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: object) -> bool:
return self is other
def __getitem__(self, key: str) -> Any:
return self._state[key]
def _check_frozen(self) -> None:
if self._frozen:
warnings.warn(
"Changing state of started or joined " "application is deprecated",
DeprecationWarning,
stacklevel=3,
)
def __setitem__(self, key: str, value: Any) -> None:
self._check_frozen()
self._state[key] = value
def __delitem__(self, key: str) -> None:
self._check_frozen()
del self._state[key]
def __len__(self) -> int:
return len(self._state)
def __iter__(self) -> Iterator[str]:
return iter(self._state)
########
@property
def loop(self) -> asyncio.AbstractEventLoop:
# Technically the loop can be None
# but we mask it by explicit type cast
# to provide more convinient type annotation
warnings.warn("loop property is deprecated", DeprecationWarning, stacklevel=2)
return cast(asyncio.AbstractEventLoop, self._loop)
def _set_loop(self, loop: Optional[asyncio.AbstractEventLoop]) -> 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"
)
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 pre_frozen(self) -> bool:
return self._pre_frozen
def pre_freeze(self) -> None:
if self._pre_frozen:
return
self._pre_frozen = True
self._middlewares.freeze()
self._router.freeze()
self._on_response_prepare.freeze()
self._cleanup_ctx.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.pre_freeze()
self._run_middlewares = self._run_middlewares or subapp._run_middlewares
@property
def frozen(self) -> bool:
return self._frozen
def freeze(self) -> None:
if self._frozen:
return
self.pre_freeze()
self._frozen = True
for subapp in self._subapps:
subapp.freeze()
@property
def debug(self) -> bool:
warnings.warn("debug property is deprecated", DeprecationWarning, stacklevel=2)
return self._debug # type: ignore[no-any-return]
def _reg_subapp_signals(self, subapp: "Application") -> None:
def reg_handler(signame: str) -> None:
subsig = getattr(subapp, signame)
async def handler(app: "Application") -> None:
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: str, subapp: "Application") -> AbstractResource:
if not isinstance(prefix, str):
raise TypeError("Prefix must be str")
prefix = prefix.rstrip("/")
if not prefix:
raise ValueError("Prefix cannot be empty")
factory = partial(PrefixedSubAppResource, prefix, subapp)
return self._add_subapp(factory, subapp)
def _add_subapp(
self, resource_factory: Callable[[], AbstractResource], subapp: "Application"
) -> AbstractResource:
if self.frozen:
raise RuntimeError("Cannot add sub application to frozen application")
if subapp.frozen:
raise RuntimeError("Cannot add frozen application")
resource = resource_factory()
self.router.register_resource(resource)
self._reg_subapp_signals(subapp)
self._subapps.append(subapp)
subapp.pre_freeze()
if self._loop is not None:
subapp._set_loop(self._loop)
return resource
def add_domain(self, domain: str, subapp: "Application") -> AbstractResource:
if not isinstance(domain, str):
raise TypeError("Domain must be str")
elif "*" in domain:
rule: Domain = MaskDomain(domain)
else:
rule = Domain(domain)
factory = partial(MatchedSubAppResource, rule, subapp)
return self._add_subapp(factory, subapp)
def add_routes(self, routes: Iterable[AbstractRouteDef]) -> List[AbstractRoute]:
return self.router.add_routes(routes)
@property
def on_response_prepare(self) -> _RespPrepareSignal:
return self._on_response_prepare
@property
def on_startup(self) -> _AppSignal:
return self._on_startup
@property
def on_shutdown(self) -> _AppSignal:
return self._on_shutdown
@property
def on_cleanup(self) -> _AppSignal:
return self._on_cleanup
@property
def cleanup_ctx(self) -> "CleanupContext":
return self._cleanup_ctx
@property
def router(self) -> UrlDispatcher:
return self._router
@property
def middlewares(self) -> _Middlewares:
return self._middlewares
def _make_handler(
self,
*,
loop: Optional[asyncio.AbstractEventLoop] = None,
access_log_class: Type[AbstractAccessLogger] = AccessLogger,
**kwargs: Any,
) -> Server:
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
kwargs["access_log_class"] = access_log_class
if self._handler_args:
for k, v in self._handler_args.items():
kwargs[k] = v
return Server(
self._handle, # type: ignore[arg-type]
request_factory=self._make_request,
loop=self._loop,
**kwargs,
)
def make_handler(
self,
*,
loop: Optional[asyncio.AbstractEventLoop] = None,
access_log_class: Type[AbstractAccessLogger] = AccessLogger,
**kwargs: Any,
) -> Server:
warnings.warn(
"Application.make_handler(...) is deprecated, " "use AppRunner API instead",
DeprecationWarning,
stacklevel=2,
)
return self._make_handler(
loop=loop, access_log_class=access_log_class, **kwargs
)
async def startup(self) -> None:
"""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) -> None:
"""Causes on_shutdown signal
Should be called before cleanup()
"""
await self.on_shutdown.send(self)
async def cleanup(self) -> None:
"""Causes on_cleanup signal
Should be called after shutdown()
"""
if self.on_cleanup.frozen:
await self.on_cleanup.send(self)
else:
# If an exception occurs in startup, ensure cleanup contexts are completed.
await self._cleanup_ctx._on_cleanup(self)
def _make_request(
self,
message: RawRequestMessage,
payload: StreamReader,
protocol: RequestHandler,
writer: AbstractStreamWriter,
task: "asyncio.Task[None]",
_cls: Type[Request] = Request,
) -> Request:
return _cls(
message,
payload,
protocol,
writer,
task,
self._loop,
client_max_size=self._client_max_size,
)
def _prepare_middleware(self) -> Iterator[Tuple[_Middleware, bool]]:
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: Request) -> StreamResponse:
loop = asyncio.get_event_loop()
debug = loop.get_debug()
match_info = await self._router.resolve(request)
if debug: # pragma: no cover
if not isinstance(match_info, AbstractMatchInfo):
raise TypeError(
"match_info should be AbstractMatchInfo "
"instance, not {!r}".format(match_info)
)
match_info.add_app(self)
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: # type: ignore[union-attr] # noqa
if new_style:
handler = update_wrapper(
partial(m, handler=handler), handler
)
else:
handler = await m(app, handler) # type: ignore[arg-type]
resp = await handler(request)
return resp
def __call__(self) -> "Application":
"""gunicorn compatibility"""
return self
def __repr__(self) -> str:
return f"<Application 0x{id(self):x}>"
def __bool__(self) -> bool:
return True
class CleanupError(RuntimeError):
@property
def exceptions(self) -> List[BaseException]:
return cast(List[BaseException], self.args[1])
if TYPE_CHECKING: # pragma: no cover
_CleanupContextBase = FrozenList[Callable[[Application], AsyncIterator[None]]]
else:
_CleanupContextBase = FrozenList
class CleanupContext(_CleanupContextBase):
def __init__(self) -> None:
super().__init__()
self._exits: List[AsyncIterator[None]] = []
async def _on_startup(self, app: Application) -> None:
for cb in self:
it = cb(app).__aiter__()
await it.__anext__()
self._exits.append(it)
async def _on_cleanup(self, app: Application) -> None:
errors = []
for it in reversed(self._exits):
try:
await it.__anext__()
except StopAsyncIteration:
pass
except Exception as exc:
errors.append(exc)
else:
errors.append(RuntimeError(f"{it!r} has more than one 'yield'"))
if errors:
if len(errors) == 1:
raise errors[0]
else:
raise CleanupError("Multiple errors on cleanup stage", errors)