import asyncio import json import typing from collections.abc import Mapping from http import cookies as http_cookies from starlette.datastructures import URL, Address, FormData, Headers, QueryParams, State from starlette.formparsers import FormParser, MultiPartParser from starlette.types import Message, Receive, Scope, Send try: from multipart.multipart import parse_options_header except ImportError: # pragma: nocover parse_options_header = None SERVER_PUSH_HEADERS_TO_COPY = { "accept", "accept-encoding", "accept-language", "cache-control", "user-agent", } def cookie_parser(cookie_string: str) -> typing.Dict[str, str]: """ This function parses a ``Cookie`` HTTP header into a dict of key/value pairs. It attempts to mimic browser cookie parsing behavior: browsers and web servers frequently disregard the spec (RFC 6265) when setting and reading cookies, so we attempt to suit the common scenarios here. This function has been adapted from Django 3.1.0. Note: we are explicitly _NOT_ using `SimpleCookie.load` because it is based on an outdated spec and will fail on lots of input we want to support """ cookie_dict: typing.Dict[str, str] = {} for chunk in cookie_string.split(";"): if "=" in chunk: key, val = chunk.split("=", 1) else: # Assume an empty name per # https://bugzilla.mozilla.org/show_bug.cgi?id=169091 key, val = "", chunk key, val = key.strip(), val.strip() if key or val: # unquote using Python's algorithm. cookie_dict[key] = http_cookies._unquote(val) # type: ignore return cookie_dict class ClientDisconnect(Exception): pass class HTTPConnection(Mapping): """ A base class for incoming HTTP connections, that is used to provide any functionality that is common to both `Request` and `WebSocket`. """ def __init__(self, scope: Scope, receive: Receive = None) -> None: assert scope["type"] in ("http", "websocket") self.scope = scope def __getitem__(self, key: str) -> str: return self.scope[key] def __iter__(self) -> typing.Iterator[str]: return iter(self.scope) def __len__(self) -> int: return len(self.scope) @property def app(self) -> typing.Any: return self.scope["app"] @property def url(self) -> URL: if not hasattr(self, "_url"): self._url = URL(scope=self.scope) return self._url @property def base_url(self) -> URL: if not hasattr(self, "_base_url"): base_url_scope = dict(self.scope) base_url_scope["path"] = "/" base_url_scope["query_string"] = b"" base_url_scope["root_path"] = base_url_scope.get( "app_root_path", base_url_scope.get("root_path", "") ) self._base_url = URL(scope=base_url_scope) return self._base_url @property def headers(self) -> Headers: if not hasattr(self, "_headers"): self._headers = Headers(scope=self.scope) return self._headers @property def query_params(self) -> QueryParams: if not hasattr(self, "_query_params"): self._query_params = QueryParams(self.scope["query_string"]) return self._query_params @property def path_params(self) -> dict: return self.scope.get("path_params", {}) @property def cookies(self) -> typing.Dict[str, str]: if not hasattr(self, "_cookies"): cookies: typing.Dict[str, str] = {} cookie_header = self.headers.get("cookie") if cookie_header: cookies = cookie_parser(cookie_header) self._cookies = cookies return self._cookies @property def client(self) -> Address: host, port = self.scope.get("client") or (None, None) return Address(host=host, port=port) @property def session(self) -> dict: assert ( "session" in self.scope ), "SessionMiddleware must be installed to access request.session" return self.scope["session"] @property def auth(self) -> typing.Any: assert ( "auth" in self.scope ), "AuthenticationMiddleware must be installed to access request.auth" return self.scope["auth"] @property def user(self) -> typing.Any: assert ( "user" in self.scope ), "AuthenticationMiddleware must be installed to access request.user" return self.scope["user"] @property def state(self) -> State: if not hasattr(self, "_state"): # Ensure 'state' has an empty dict if it's not already populated. self.scope.setdefault("state", {}) # Create a state instance with a reference to the dict in which it should # store info self._state = State(self.scope["state"]) return self._state def url_for(self, name: str, **path_params: typing.Any) -> str: router = self.scope["router"] url_path = router.url_path_for(name, **path_params) return url_path.make_absolute_url(base_url=self.base_url) async def empty_receive() -> Message: raise RuntimeError("Receive channel has not been made available") async def empty_send(message: Message) -> None: raise RuntimeError("Send channel has not been made available") class Request(HTTPConnection): def __init__( self, scope: Scope, receive: Receive = empty_receive, send: Send = empty_send ): super().__init__(scope) assert scope["type"] == "http" self._receive = receive self._send = send self._stream_consumed = False self._is_disconnected = False @property def method(self) -> str: return self.scope["method"] @property def receive(self) -> Receive: return self._receive async def stream(self) -> typing.AsyncGenerator[bytes, None]: if hasattr(self, "_body"): yield self._body yield b"" return if self._stream_consumed: raise RuntimeError("Stream consumed") self._stream_consumed = True while True: message = await self._receive() if message["type"] == "http.request": body = message.get("body", b"") if body: yield body if not message.get("more_body", False): break elif message["type"] == "http.disconnect": self._is_disconnected = True raise ClientDisconnect() yield b"" async def body(self) -> bytes: if not hasattr(self, "_body"): chunks = [] async for chunk in self.stream(): chunks.append(chunk) self._body = b"".join(chunks) return self._body async def json(self) -> typing.Any: if not hasattr(self, "_json"): body = await self.body() self._json = json.loads(body) return self._json async def form(self) -> FormData: if not hasattr(self, "_form"): assert ( parse_options_header is not None ), "The `python-multipart` library must be installed to use form parsing." content_type_header = self.headers.get("Content-Type") content_type, options = parse_options_header(content_type_header) if content_type == b"multipart/form-data": multipart_parser = MultiPartParser(self.headers, self.stream()) self._form = await multipart_parser.parse() elif content_type == b"application/x-www-form-urlencoded": form_parser = FormParser(self.headers, self.stream()) self._form = await form_parser.parse() else: self._form = FormData() return self._form async def close(self) -> None: if hasattr(self, "_form"): await self._form.close() async def is_disconnected(self) -> bool: if not self._is_disconnected: try: message = await asyncio.wait_for(self._receive(), timeout=0.0000001) except asyncio.TimeoutError: message = {} if message.get("type") == "http.disconnect": self._is_disconnected = True return self._is_disconnected async def send_push_promise(self, path: str) -> None: if "http.response.push" in self.scope.get("extensions", {}): raw_headers = [] for name in SERVER_PUSH_HEADERS_TO_COPY: for value in self.headers.getlist(name): raw_headers.append( (name.encode("latin-1"), value.encode("latin-1")) ) await self._send( {"type": "http.response.push", "path": path, "headers": raw_headers} )