homeassistant: Strengthen types using WildVale.

zerver/webhooks/homeassistant/view.py

@@ -1,10 +1,9 @@
-from typing import Dict
-
 from django.http import HttpRequest, HttpResponse
 
 from zerver.decorator import webhook_view
 from zerver.lib.request import REQ, has_request_variables
 from zerver.lib.response import json_success
+from zerver.lib.validator import WildValue, check_string, to_wild_value
 from zerver.lib.webhooks.common import check_send_webhook_message
 from zerver.models import UserProfile
 
@@ -14,15 +13,15 @@ from zerver.models import UserProfile
 def api_homeassistant_webhook(
     request: HttpRequest,
     user_profile: UserProfile,
-    payload: Dict[str, str] = REQ(argument_type="body"),
+    payload: WildValue = REQ(argument_type="body", converter=to_wild_value),
 ) -> HttpResponse:
 
     # construct the body of the message
-    body = payload["message"]
+    body = payload["message"].tame(check_string)
 
     # set the topic to the topic parameter, if given
     if "topic" in payload:
-        topic = payload["topic"]
+        topic = payload["topic"].tame(check_string)
     else:
         topic = "homeassistant"