uptimerobot: Strengthen types using WildValue.

This commit strengthens types by typing the webhook's incoming
payload as WildValue and taming the values of the payload before
usage, which eradicates the use of Any within the UptimeRobot
incoming webhook integration.

The payload's values are now tamed, stored in variables and passed
into message templates as opposed to passing in the payload dict as
keyword arguments.

The KeyError exception has been replaced to catch a ValidationError
instead now, since the incoming payload's keys will be tamed before
usage and the non-existence of the key is raised as a
ValidationError in the taming function.

zerver/webhooks/uptimerobot/view.py

@@ -1,5 +1,4 @@
-from typing import Any, Dict
-
+from django.core.exceptions import ValidationError
 from django.http import HttpRequest, HttpResponse
 from django.utils.translation import gettext as _
 
@@ -9,6 +8,7 @@ from zerver.lib.exceptions import JsonableError
 from zerver.lib.request import REQ, has_request_variables
 from zerver.lib.response import json_success
 from zerver.lib.send_email import FromAddress
+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
 
@@ -36,17 +36,18 @@ ALL_EVENT_TYPES = ["up", "down"]
 def api_uptimerobot_webhook(
     request: HttpRequest,
     user_profile: UserProfile,
-    payload: Dict[str, Any] = REQ(argument_type="body"),
+    payload: WildValue = REQ(argument_type="body", converter=to_wild_value),
 ) -> HttpResponse:
-    if payload["alert_type_friendly_name"] == "Up":
+    event_type = payload["alert_type_friendly_name"].tame(check_string)
+    if event_type == "Up":
         event = "up"
-    elif payload["alert_type_friendly_name"] == "Down":
+    elif event_type == "Down":
         event = "down"
 
     try:
-        body = get_body_for_http_request(payload)
+        body = get_body_for_http_request(payload, event_type)
         subject = get_subject_for_http_request(payload)
-    except KeyError:
+    except ValidationError:
         message = MISCONFIGURED_PAYLOAD_ERROR_MESSAGE.format(
             bot_name=user_profile.full_name,
             support_email=FromAddress.SUPPORT,
@@ -59,14 +60,32 @@ def api_uptimerobot_webhook(
     return json_success(request)
 
 
-def get_subject_for_http_request(payload: Dict[str, Any]) -> str:
-    return UPTIMEROBOT_TOPIC_TEMPLATE.format(monitor_friendly_name=payload["monitor_friendly_name"])
+def get_subject_for_http_request(payload: WildValue) -> str:
+    return UPTIMEROBOT_TOPIC_TEMPLATE.format(
+        monitor_friendly_name=payload["monitor_friendly_name"].tame(check_string)
+    )
 
 
-def get_body_for_http_request(payload: Dict[str, Any]) -> str:
-    if payload["alert_type_friendly_name"] == "Up":
-        body = UPTIMEROBOT_MESSAGE_UP_TEMPLATE.format(**payload)
-    elif payload["alert_type_friendly_name"] == "Down":
-        body = UPTIMEROBOT_MESSAGE_DOWN_TEMPLATE.format(**payload)
+def get_body_for_http_request(payload: WildValue, event_type: str) -> str:
+    if event_type == "Up":
+        monitor_friendly_name = payload["monitor_friendly_name"].tame(check_string)
+        monitor_url = payload["monitor_url"].tame(check_string)
+        alert_details = payload["alert_details"].tame(check_string)
+        alert_friendly_duration = payload["alert_friendly_duration"].tame(check_string)
+        body = UPTIMEROBOT_MESSAGE_UP_TEMPLATE.format(
+            monitor_friendly_name=monitor_friendly_name,
+            monitor_url=monitor_url,
+            alert_details=alert_details,
+            alert_friendly_duration=alert_friendly_duration,
+        )
+    elif event_type == "Down":
+        monitor_friendly_name = payload["monitor_friendly_name"].tame(check_string)
+        monitor_url = payload["monitor_url"].tame(check_string)
+        alert_details = payload["alert_details"].tame(check_string)
+        body = UPTIMEROBOT_MESSAGE_DOWN_TEMPLATE.format(
+            monitor_friendly_name=monitor_friendly_name,
+            monitor_url=monitor_url,
+            alert_details=alert_details,
+        )
 
     return body