Add type annotation to wsproto_impl.py (#1754)

* Add type annotation to `wsproto_impl.py`

* add typpeddict ignore

* add websocket accept type

* add list extension

* create event variable

* add send and close event

* add literal

setup.cfg

@@ -37,6 +37,7 @@ files =
     uvicorn/protocols/http/__init__.py,
     uvicorn/protocols/websockets/__init__.py,
     uvicorn/protocols/websockets/websockets_impl.py,
+    uvicorn/protocols/websockets/wsproto_impl.py,
     uvicorn/protocols/http/h11_impl.py,
     uvicorn/protocols/http/httptools_impl.py,
     tests/middleware/test_wsgi.py,

uvicorn/protocols/websockets/wsproto_impl.py

@@ -1,25 +1,57 @@
 import asyncio
 import logging
+import sys
+import typing
 from urllib.parse import unquote
 
 import h11
 import wsproto
 from wsproto import ConnectionType, events
 from wsproto.connection import ConnectionState
-from wsproto.extensions import PerMessageDeflate
+from wsproto.extensions import Extension, PerMessageDeflate
 from wsproto.utilities import RemoteProtocolError
 
+from uvicorn.config import Config
 from uvicorn.logging import TRACE_LOG_LEVEL
 from uvicorn.protocols.utils import (
     get_local_addr,
     get_path_with_query_string,
     get_remote_addr,
     is_ssl,
 )
+from uvicorn.server import ServerState
+
+if typing.TYPE_CHECKING:
+    from asgiref.typing import (
+        ASGISendEvent,
+        WebSocketAcceptEvent,
+        WebSocketCloseEvent,
+        WebSocketConnectEvent,
+        WebSocketDisconnectEvent,
+        WebSocketReceiveEvent,
+        WebSocketScope,
+        WebSocketSendEvent,
+    )
+
+    WebSocketEvent = typing.Union[
+        "WebSocketReceiveEvent",
+        "WebSocketDisconnectEvent",
+        "WebSocketConnectEvent",
+    ]
+
+if sys.version_info < (3, 8):  # pragma: py-gte-38
+    from typing_extensions import Literal
+else:  # pragma: py-lt-38
+    from typing import Literal
 
 
 class WSProtocol(asyncio.Protocol):
-    def __init__(self, config, server_state, _loop=None):
+    def __init__(
+        self,
+        config: Config,
+        server_state: ServerState,
+        _loop: typing.Optional[asyncio.AbstractEventLoop] = None,
+    ) -> None:
         if not config.loaded:
             config.load()
 
@@ -35,14 +67,13 @@ def __init__(self, config, server_state, _loop=None):
         self.default_headers = server_state.default_headers
 
         # Connection state
-        self.transport = None
-        self.server = None
-        self.client = None
-        self.scheme = None
+        self.transport: asyncio.Transport = None  # type: ignore[assignment]
+        self.server: typing.Optional[typing.Tuple[str, int]] = None
+        self.client: typing.Optional[typing.Tuple[str, int]] = None
+        self.scheme: Literal["wss", "ws"] = None  # type: ignore[assignment]
 
         # WebSocket state
-        self.connect_event = None
-        self.queue = asyncio.Queue()
+        self.queue: asyncio.Queue["WebSocketEvent"] = asyncio.Queue()
         self.handshake_complete = False
         self.close_sent = False
 
@@ -58,43 +89,46 @@ def __init__(self, config, server_state, _loop=None):
 
     # Protocol interface
 
-    def connection_made(self, transport):
+    def connection_made(  # type: ignore[override]
+        self, transport: asyncio.Transport
+    ) -> None:
         self.connections.add(self)
         self.transport = transport
         self.server = get_local_addr(transport)
         self.client = get_remote_addr(transport)
         self.scheme = "wss" if is_ssl(transport) else "ws"
 
         if self.logger.level <= TRACE_LOG_LEVEL:
-            prefix = "%s:%d - " % tuple(self.client) if self.client else ""
+            prefix = "%s:%d - " % self.client if self.client else ""
             self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection made", prefix)
 
-    def connection_lost(self, exc):
+    def connection_lost(self, exc: typing.Optional[Exception]) -> None:
         code = 1005 if self.handshake_complete else 1006
         self.queue.put_nowait({"type": "websocket.disconnect", "code": code})
         self.connections.remove(self)
 
         if self.logger.level <= TRACE_LOG_LEVEL:
-            prefix = "%s:%d - " % tuple(self.client) if self.client else ""
+            prefix = "%s:%d - " % self.client if self.client else ""
             self.logger.log(TRACE_LOG_LEVEL, "%sWebSocket connection lost", prefix)
 
         self.handshake_complete = True
         if exc is None:
             self.transport.close()
 
-    def eof_received(self):
+    def eof_received(self) -> None:
         pass
 
-    def data_received(self, data):
+    def data_received(self, data: bytes) -> None:
         try:
             self.conn.receive_data(data)
         except RemoteProtocolError as err:
-            self.transport.write(self.conn.send(err.event_hint))
+            # TODO: Remove `type: ignore` when wsproto fixes the type annotation.
+            self.transport.write(self.conn.send(err.event_hint))  # type: ignore[arg-type]  # noqa: E501
             self.transport.close()
         else:
             self.handle_events()
 
-    def handle_events(self):
+    def handle_events(self) -> None:
         for event in self.conn.events():
             if isinstance(event, events.Request):
                 self.handle_connect(event)
@@ -107,19 +141,19 @@ def handle_events(self):
             elif isinstance(event, events.Ping):
                 self.handle_ping(event)
 
-    def pause_writing(self):
+    def pause_writing(self) -> None:
         """
         Called by the transport when the write buffer exceeds the high water mark.
         """
         self.writable.clear()
 
-    def resume_writing(self):
+    def resume_writing(self) -> None:
         """
         Called by the transport when the write buffer drops below the low water mark.
         """
         self.writable.set()
 
-    def shutdown(self):
+    def shutdown(self) -> None:
         if self.handshake_complete:
             self.queue.put_nowait({"type": "websocket.disconnect", "code": 1012})
             output = self.conn.send(wsproto.events.CloseConnection(code=1012))
@@ -128,17 +162,16 @@ def shutdown(self):
             self.send_500_response()
         self.transport.close()
 
-    def on_task_complete(self, task):
+    def on_task_complete(self, task: asyncio.Task) -> None:
         self.tasks.discard(task)
 
     # Event handlers
 
-    def handle_connect(self, event):
-        self.connect_event = event
+    def handle_connect(self, event: events.Request) -> None:
         headers = [(b"host", event.host.encode())]
         headers += [(key.lower(), value) for key, value in event.extra_headers]
         raw_path, _, query_string = event.target.partition("?")
-        self.scope = {
+        self.scope: "WebSocketScope" = {
             "type": "websocket",
             "asgi": {"version": self.config.asgi_version, "spec_version": "2.3"},
             "http_version": "1.1",
@@ -151,41 +184,50 @@ def handle_connect(self, event):
             "query_string": query_string.encode("ascii"),
             "headers": headers,
             "subprotocols": event.subprotocols,
+            "extensions": None,
         }
         self.queue.put_nowait({"type": "websocket.connect"})
         task = self.loop.create_task(self.run_asgi())
         task.add_done_callback(self.on_task_complete)
         self.tasks.add(task)
 
-    def handle_text(self, event):
+    def handle_text(self, event: events.TextMessage) -> None:
         self.text += event.data
         if event.message_finished:
-            self.queue.put_nowait({"type": "websocket.receive", "text": self.text})
+            msg: "WebSocketReceiveEvent" = {  # type: ignore[typeddict-item]
+                "type": "websocket.receive",
+                "text": self.text,
+            }
+            self.queue.put_nowait(msg)
             self.text = ""
             if not self.read_paused:
                 self.read_paused = True
                 self.transport.pause_reading()
 
-    def handle_bytes(self, event):
+    def handle_bytes(self, event: events.BytesMessage) -> None:
         self.bytes += event.data
         # todo: we may want to guard the size of self.bytes and self.text
         if event.message_finished:
-            self.queue.put_nowait({"type": "websocket.receive", "bytes": self.bytes})
+            msg: "WebSocketReceiveEvent" = {  # type: ignore[typeddict-item]
+                "type": "websocket.receive",
+                "bytes": self.bytes,
+            }
+            self.queue.put_nowait(msg)
             self.bytes = b""
             if not self.read_paused:
                 self.read_paused = True
                 self.transport.pause_reading()
 
-    def handle_close(self, event):
+    def handle_close(self, event: events.CloseConnection) -> None:
         if self.conn.state == ConnectionState.REMOTE_CLOSING:
             self.transport.write(self.conn.send(event.response()))
         self.queue.put_nowait({"type": "websocket.disconnect", "code": event.code})
         self.transport.close()
 
-    def handle_ping(self, event):
+    def handle_ping(self, event: events.Ping) -> None:
         self.transport.write(self.conn.send(event.response()))
 
-    def send_500_response(self):
+    def send_500_response(self) -> None:
         headers = [
             (b"content-type", b"text/plain; charset=utf-8"),
             (b"connection", b"close"),
@@ -203,7 +245,7 @@ def send_500_response(self):
             output += self.conn.send(msg)
         self.transport.write(output)
 
-    async def run_asgi(self):
+    async def run_asgi(self) -> None:
         try:
             result = await self.app(self.scope, self.receive, self.send)
         except BaseException:
@@ -222,21 +264,22 @@ async def run_asgi(self):
                 self.logger.error(msg, result)
                 self.transport.close()
 
-    async def send(self, message):
+    async def send(self, message: "ASGISendEvent") -> None:
         await self.writable.wait()
 
         message_type = message["type"]
 
         if not self.handshake_complete:
             if message_type == "websocket.accept":
+                message = typing.cast("WebSocketAcceptEvent", message)
                 self.logger.info(
                     '%s - "WebSocket %s" [accepted]',
                     self.scope["client"],
                     get_path_with_query_string(self.scope),
                 )
                 subprotocol = message.get("subprotocol")
                 extra_headers = self.default_headers + list(message.get("headers", []))
-                extensions = []
+                extensions: typing.List[Extension] = []
                 if self.config.ws_per_message_deflate:
                     extensions.append(PerMessageDeflate())
                 if not self.transport.is_closing():
@@ -259,8 +302,8 @@ async def send(self, message):
                 )
                 self.handshake_complete = True
                 self.close_sent = True
-                msg = events.RejectConnection(status_code=403, headers=[])
-                output = self.conn.send(msg)
+                event = events.RejectConnection(status_code=403, headers=[])
+                output = self.conn.send(event)
                 self.transport.write(output)
                 self.transport.close()
 
@@ -273,14 +316,18 @@ async def send(self, message):
 
         elif not self.close_sent:
             if message_type == "websocket.send":
+                message = typing.cast("WebSocketSendEvent", message)
                 bytes_data = message.get("bytes")
                 text_data = message.get("text")
                 data = text_data if bytes_data is None else bytes_data
-                output = self.conn.send(wsproto.events.Message(data=data))
+                output = self.conn.send(
+                    wsproto.events.Message(data=data)  # type: ignore[type-var]
+                )
                 if not self.transport.is_closing():
                     self.transport.write(output)
 
             elif message_type == "websocket.close":
+                message = typing.cast("WebSocketCloseEvent", message)
                 self.close_sent = True
                 code = message.get("code", 1000)
                 reason = message.get("reason", "") or ""
@@ -303,7 +350,7 @@ async def send(self, message):
             msg = "Unexpected ASGI message '%s', after sending 'websocket.close'."
             raise RuntimeError(msg % message_type)
 
-    async def receive(self):
+    async def receive(self) -> "WebSocketEvent":
         message = await self.queue.get()
         if self.read_paused and self.queue.empty():
             self.read_paused = False