Fix @reify type hints (#4736)

* Fix @reify type hints

* Fix issues with type hints

* Add a changelog

Co-authored-by: Andrew Svetlov <[email protected]>

CHANGES/4736.bugfix

@@ -0,0 +1,2 @@
+Improve typing annotations for ``web.Request``, ``aiohttp.ClientResponse`` and
+``multipart`` module.

aiohttp/client.py

@@ -522,25 +522,25 @@ async def _request(
                             resp.release()
 
                         try:
-                            r_url = URL(
+                            parsed_url = URL(
                                 r_url, encoded=not self._requote_redirect_url)
 
                         except ValueError:
                             raise InvalidURL(r_url)
 
-                        scheme = r_url.scheme
+                        scheme = parsed_url.scheme
                         if scheme not in ('http', 'https', ''):
                             resp.close()
                             raise ValueError(
                                 'Can redirect only to http or https')
                         elif not scheme:
-                            r_url = url.join(r_url)
+                            parsed_url = url.join(parsed_url)
 
-                        if url.origin() != r_url.origin():
+                        if url.origin() != parsed_url.origin():
                             auth = None
                             headers.pop(hdrs.AUTHORIZATION, None)
 
-                        url = r_url
+                        url = parsed_url
                         params = None
                         resp.release()
                         continue
@@ -737,10 +737,10 @@ async def _ws_connect(
                     headers=resp.headers)
 
             # key calculation
-            key = resp.headers.get(hdrs.SEC_WEBSOCKET_ACCEPT, '')
+            r_key = resp.headers.get(hdrs.SEC_WEBSOCKET_ACCEPT, '')
             match = base64.b64encode(
                 hashlib.sha1(sec_key + WS_KEY).digest()).decode()
-            if key != match:
+            if r_key != match:
                 raise WSServerHandshakeError(
                     resp.request_info,
                     resp.history,
@@ -780,15 +780,16 @@ async def _ws_connect(
 
             conn = resp.connection
             assert conn is not None
-            proto = conn.protocol
-            assert proto is not None
+            conn_proto = conn.protocol
+            assert conn_proto is not None
             transport = conn.transport
             assert transport is not None
             reader = FlowControlDataQueue(
-                proto, limit=2 ** 16, loop=self._loop)  # type: FlowControlDataQueue[WSMessage]  # noqa
-            proto.set_parser(WebSocketReader(reader, max_msg_size), reader)
+                conn_proto, limit=2 ** 16, loop=self._loop)  # type: FlowControlDataQueue[WSMessage]  # noqa
+            conn_proto.set_parser(
+                WebSocketReader(reader, max_msg_size), reader)
             writer = WebSocketWriter(
-                proto, transport, use_mask=True,
+                conn_proto, transport, use_mask=True,
                 compress=compress, notakeover=notakeover)
         except BaseException:
             resp.close()

aiohttp/client_exceptions.py

@@ -3,7 +3,7 @@
 import asyncio
 from typing import TYPE_CHECKING, Any, Optional, Tuple, Union
 
-from .typedefs import _CIMultiDict
+from .typedefs import LooseHeaders
 
 try:
     import ssl
@@ -22,7 +22,6 @@
 else:
     RequestInfo = ClientResponse = ConnectionKey = None
 
-
 __all__ = (
     'ClientError',
 
@@ -55,7 +54,7 @@ def __init__(self, request_info: RequestInfo,
                  history: Tuple[ClientResponse, ...], *,
                  status: Optional[int]=None,
                  message: str='',
-                 headers: Optional[_CIMultiDict]=None) -> None:
+                 headers: Optional[LooseHeaders]=None) -> None:
         self.request_info = request_info
         if status is not None:
             self.status = status

aiohttp/helpers.py

@@ -25,6 +25,7 @@
     Callable,
     Dict,
     Generator,
+    Generic,
     Iterable,
     Iterator,
     List,
@@ -66,6 +67,11 @@
 except ImportError:
     from typing_extensions import ContextManager
 
+if PY_38:
+    from typing import Protocol
+else:
+    from typing_extensions import Protocol  # type: ignore
+
 
 def all_tasks(
         loop: Optional[asyncio.AbstractEventLoop] = None
@@ -79,6 +85,7 @@ def all_tasks(
 
 
 _T = TypeVar('_T')
+_S = TypeVar('_S')
 
 
 sentinel = object()  # type: Any
@@ -382,7 +389,11 @@ def is_expected_content_type(response_content_type: str,
     return expected_content_type in response_content_type
 
 
-class reify:
+class _TSelf(Protocol):
+    _cache: Dict[str, Any]
+
+
+class reify(Generic[_T]):
     """Use as a class method decorator.  It operates almost exactly like
     the Python `@property` decorator, but it puts the result of the
     method it decorates into the instance dict after the first call,
@@ -391,12 +402,12 @@ class reify:
 
     """
 
-    def __init__(self, wrapped: Callable[..., Any]) -> None:
+    def __init__(self, wrapped: Callable[..., _T]) -> None:
         self.wrapped = wrapped
         self.__doc__ = wrapped.__doc__
         self.name = wrapped.__name__
 
-    def __get__(self, inst: Any, owner: Any) -> Any:
+    def __get__(self, inst: _TSelf, owner: Optional[Type[Any]] = None) -> _T:
         try:
             try:
                 return inst._cache[self.name]
@@ -409,7 +420,7 @@ def __get__(self, inst: Any, owner: Any) -> Any:
                 return self
             raise
 
-    def __set__(self, inst: Any, value: Any) -> None:
+    def __set__(self, inst: _TSelf, value: _T) -> None:
         raise AttributeError("reified property is read-only")
 
 

aiohttp/http_websocket.py

@@ -152,7 +152,8 @@ def _websocket_mask_python(mask: bytes, data: bytearray) -> None:
 _WS_EXT_RE_SPLIT = re.compile(r'permessage-deflate([^,]+)?')
 
 
-def ws_ext_parse(extstr: str, isserver: bool=False) -> Tuple[int, bool]:
+def ws_ext_parse(extstr: Optional[str],
+                 isserver: bool=False) -> Tuple[int, bool]:
     if not extstr:
         return 0, False
 

aiohttp/web_request.py

@@ -39,6 +39,7 @@
     set_result,
 )
 from .http_parser import RawRequestMessage
+from .http_writer import HttpVersion
 from .multipart import BodyPartReader, MultipartReader
 from .streams import EmptyStreamReader, StreamReader
 from .typedefs import (
@@ -343,7 +344,7 @@ def method(self) -> str:
         return self._method
 
     @reify
-    def version(self) -> Tuple[int, int]:
+    def version(self) -> HttpVersion:
         """Read only property for getting HTTP version of request.
 
         Returns aiohttp.protocol.HttpVersion instance.
@@ -434,7 +435,7 @@ def raw_headers(self) -> RawHeaders:
         return self._message.raw_headers
 
     @staticmethod
-    def _http_date(_date_str: str) -> Optional[datetime.datetime]:
+    def _http_date(_date_str: Optional[str]) -> Optional[datetime.datetime]:
         """Process a date string, return a datetime object
         """
         if _date_str is not None:
@@ -618,6 +619,7 @@ async def post(self) -> 'MultiDictProxy[Union[str, bytes, FileField]]':
                 field_ct = field.headers.get(hdrs.CONTENT_TYPE)
 
                 if isinstance(field, BodyPartReader):
+                    assert field.name is not None
                     if field.filename and field_ct:
                         # store file in temp file
                         tmp = tempfile.TemporaryFile()

aiohttp/web_urldispatcher.py

@@ -264,7 +264,7 @@ async def _default_expect_handler(request: Request) -> None:
     Just send "100 Continue" to client.
     raise HTTPExpectationFailed if value of header is not "100-continue"
     """
-    expect = request.headers.get(hdrs.EXPECT)
+    expect = request.headers.get(hdrs.EXPECT, "")
     if request.version == HttpVersion11:
         if expect.lower() == "100-continue":
             await request.writer.write(b"HTTP/1.1 100 Continue\r\n\r\n")
@@ -749,7 +749,9 @@ def validation(self, domain: str) -> str:
 
     async def match(self, request: Request) -> bool:
         host = request.headers.get(hdrs.HOST)
-        return host and self.match_domain(host)
+        if not host:
+            return False
+        return self.match_domain(host)
 
     def match_domain(self, host: str) -> bool:
         return host.lower() == self._domain