improve ws connection spam filter

quiz/quiz.py

@@ -2,6 +2,7 @@ import asyncio
 import logging
 import unicodedata
 from dataclasses import dataclass, field
+from http import HTTPStatus
 from json import dumps, loads
 from secrets import compare_digest, token_hex
 from time import perf_counter_ns
@@ -304,14 +305,6 @@ async def juggle(client: Client):
 
 
 async def connected(ws: Websocket, path: str):
-    # We'll throw out anything not starting with a certain path prefix just to
-    # get rid of internet spam - mass scans for security problems, etc.
-    # No need to waste resources on this kinda crap.
-    # Ideally the same rule should already be enforced by an upstream proxy.
-    if not path.startswith(config.path_prefix):
-        await ws.close()
-        return
-
     path = printable(path)
 
     client = Client(ws, path)
@@ -344,5 +337,14 @@ async def connected(ws: Websocket, path: str):
             log.info("[%s] session gone: %s", client, session)
 
 
+async def check_path(path: str, request_headers) -> Optional["websockets.HTTPResponse"]:
+    # We'll throw out anything not starting with a certain path prefix just to
+    # get rid of internet spam - mass scans for security problems, etc.
+    # No need to waste resources on this kinda crap.
+    # Ideally the same rule should already be enforced by an upstream proxy.
+    if not path.startswith(config.path_prefix):
+        return (HTTPStatus.FORBIDDEN, {}, b"")
+
+
 def server(host: str, port: int):
-    return websockets.serve(connected, host, port)
+    return websockets.serve(connected, host, port, process_request=check_path)