Share socket on Windows

uvicorn/__main__.py

@@ -1,5 +1,4 @@
 import uvicorn
 
-
 if __name__ == "__main__":
     uvicorn.main()

uvicorn/config.py

@@ -1,6 +1,8 @@
 import asyncio
 import inspect
 import logging
+import os
+import platform
 import socket
 import ssl
 import sys
@@ -26,8 +28,8 @@
     "httptools": "uvicorn.protocols.http.httptools_impl:HttpToolsProtocol",
 }
 WS_PROTOCOLS = {
-    "none": None,
     "auto": "uvicorn.protocols.websockets.auto:AutoWebSocketsProtocol",
+    "none": None,
     "websockets": "uvicorn.protocols.websockets.websockets_impl:WebSocketProtocol",
     "wsproto": "uvicorn.protocols.websockets.wsproto_impl:WSProtocol",
 }
@@ -225,11 +227,20 @@ def bind_socket(self):
         sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
         sock.bind((self.host, self.port))
         sock.set_inheritable(True)
+
+        if platform.system() == "Windows" and (self.workers > 1 or self.should_reload):
+            #  We need to explicitly share the socket on Windows.
+            sock = socket.fromshare(sock.share(os.getpid()))
+
         message = "Uvicorn running on %s://%s:%d (Press CTRL+C to quit)"
         protocol_name = "https" if self.is_ssl else "http"
         self.logger_instance.info(message % (protocol_name, self.host, self.port))
         return sock
 
+    @property
+    def should_reload(self):
+        return isinstance(self.app, str) and (self.debug or self.reload)
+
     @property
     def logger_instance(self):
         if self.logger is not None:

uvicorn/main.py

@@ -28,7 +28,7 @@
 HTTP_CHOICES = click.Choice(HTTP_PROTOCOLS.keys())
 WS_CHOICES = click.Choice(WS_PROTOCOLS.keys())
 LIFESPAN_CHOICES = click.Choice(LIFESPAN.keys())
-LOOP_CHOICES = click.Choice(LOOP_SETUPS.keys())
+LOOP_CHOICES = click.Choice([key for key in LOOP_SETUPS.keys() if key != "none"])
 INTERFACE_CHOICES = click.Choice(INTERFACES)
 
 HANDLED_SIGNALS = (
@@ -267,7 +267,7 @@ def run(app, **kwargs):
             "auto-reload only works when app is passed as an import string."
         )
 
-    if isinstance(app, str) and (config.debug or config.reload):
+    if config.should_reload:
         sock = config.bind_socket()
         supervisor = StatReload(config)
         supervisor.run(server.run, sockets=[sock])

uvicorn/workers.py

@@ -1,6 +1,7 @@
 import asyncio
 
 from gunicorn.workers.base import Worker
+
 from uvicorn.config import Config
 from uvicorn.main import Server