import asyncio
import logging
from abc import ABC, abstractmethod
from collections.abc import Sized
from http.cookies import BaseCookie, Morsel
from typing import (
TYPE_CHECKING,
Any,
Awaitable,
Callable,
Dict,
Generator,
Iterable,
List,
Optional,
Tuple,
)
from multidict import CIMultiDict
from yarl import URL
from .helpers import get_running_loop
from .typedefs import LooseCookies
if TYPE_CHECKING:
from .web_app import Application
from .web_exceptions import HTTPException
from .web_request import BaseRequest, Request
from .web_response import StreamResponse
else:
BaseRequest = Request = Application = StreamResponse = None
HTTPException = None
class AbstractRouter(ABC):
def __init__(self) -> None:
self._frozen = False
def post_init(self, app: Application) -> None:
"""Post init stage.
Not an abstract method for sake of backward compatibility,
but if the router wants to be aware of the application
it can override this.
"""
@property
def frozen(self) -> bool:
return self._frozen
def freeze(self) -> None:
"""Freeze router."""
self._frozen = True
@abstractmethod
async def resolve(self, request: Request) -> "AbstractMatchInfo":
"""Return MATCH_INFO for given request"""
class AbstractMatchInfo(ABC):
@property # pragma: no branch
@abstractmethod
def handler(self) -> Callable[[Request], Awaitable[StreamResponse]]:
"""Execute matched request handler"""
@property
@abstractmethod
def expect_handler(
self,
) -> Callable[[Request], Awaitable[Optional[StreamResponse]]]:
"""Expect handler for 100-continue processing"""
@property # pragma: no branch
@abstractmethod
def http_exception(self) -> Optional[HTTPException]:
"""HTTPException instance raised on router's resolving, or None"""
@abstractmethod # pragma: no branch
def get_info(self) -> Dict[str, Any]:
"""Return a dict with additional info useful for introspection"""
@property # pragma: no branch
@abstractmethod
def apps(self) -> Tuple[Application, ...]:
"""Stack of nested applications.
Top level application is left-most element.
"""
@abstractmethod
def add_app(self, app: Application) -> None:
"""Add application to the nested apps stack."""
@abstractmethod
def freeze(self) -> None:
"""Freeze the match info.
The method is called after route resolution.
After the call .add_app() is forbidden.
"""
class AbstractView(ABC):
"""Abstract class based view."""
def __init__(self, request: Request) -> None:
self._request = request
@property
def request(self) -> Request:
"""Request instance."""
return self._request
@abstractmethod
def __await__(self) -> Generator[Any, None, StreamResponse]:
"""Execute the view handler."""
class AbstractResolver(ABC):
"""Abstract DNS resolver."""
@abstractmethod
async def resolve(self, host: str, port: int, family: int) -> List[Dict[str, Any]]:
"""Return IP address for given hostname"""
@abstractmethod
async def close(self) -> None:
"""Release resolver"""
if TYPE_CHECKING:
IterableBase = Iterable[Morsel[str]]
else:
IterableBase = Iterable
ClearCookiePredicate = Callable[["Morsel[str]"], bool]
class AbstractCookieJar(Sized, IterableBase):
"""Abstract Cookie Jar."""
def __init__(self, *, loop: Optional[asyncio.AbstractEventLoop] = None) -> None:
self._loop = get_running_loop(loop)
@abstractmethod
def clear(self, predicate: Optional[ClearCookiePredicate] = None) -> None:
"""Clear all cookies if no predicate is passed."""
@abstractmethod
def clear_domain(self, domain: str) -> None:
"""Clear all cookies for domain and all subdomains."""
@abstractmethod
def update_cookies(self, cookies: LooseCookies, response_url: URL = URL()) -> None:
"""Update cookies."""
@abstractmethod
def filter_cookies(self, request_url: URL) -> "BaseCookie[str]":
"""Return the jar's cookies filtered by their attributes."""
class AbstractStreamWriter(ABC):
"""Abstract stream writer."""
buffer_size = 0
output_size = 0
length: Optional[int] = 0
@abstractmethod
async def write(self, chunk: bytes) -> None:
"""Write chunk into stream."""
@abstractmethod
async def write_eof(self, chunk: bytes = b"") -> None:
"""Write last chunk."""
@abstractmethod
async def drain(self) -> None:
"""Flush the write buffer."""
@abstractmethod
def enable_compression(self, encoding: str = "deflate") -> None:
"""Enable HTTP body compression"""
@abstractmethod
def enable_chunking(self) -> None:
"""Enable HTTP chunked mode"""
@abstractmethod
async def write_headers(
self, status_line: str, headers: "CIMultiDict[str]"
) -> None:
"""Write HTTP headers"""
class AbstractAccessLogger(ABC):
"""Abstract writer to access log."""
def __init__(self, logger: logging.Logger, log_format: str) -> None:
self.logger = logger
self.log_format = log_format
@abstractmethod
def log(self, request: BaseRequest, response: StreamResponse, time: float) -> None:
"""Emit log to logger."""
