scheduled_messages: Extract method to get undelivered scheduled messages.

This also changes key for `ID` of scheduled message from `message_id`
to `scheduled_message_id`.

zerver/lib/scheduled_messages.py

@@ -1,7 +1,9 @@
+from typing import List
+
 from django.utils.translation import gettext as _
 
 from zerver.lib.exceptions import ResourceNotFoundError
-from zerver.models import ScheduledMessage, UserProfile
+from zerver.models import ScheduledMessage, ScheduledMessageDict, UserProfile
 
 
 def access_scheduled_message(
@@ -11,3 +13,13 @@ def access_scheduled_message(
         return ScheduledMessage.objects.get(id=scheduled_message_id, sender=user_profile)
     except ScheduledMessage.DoesNotExist:
         raise ResourceNotFoundError(_("Scheduled message does not exist"))
+
+
+def get_undelivered_scheduled_messages(user_profile: UserProfile) -> List[ScheduledMessageDict]:
+    scheduled_messages = ScheduledMessage.objects.filter(
+        sender=user_profile, delivered=False, delivery_type=ScheduledMessage.SEND_LATER
+    ).order_by("scheduled_timestamp")
+    scheduled_message_dicts: List[ScheduledMessageDict] = [
+        scheduled_message.to_dict() for scheduled_message in scheduled_messages
+    ]
+    return scheduled_message_dicts

zerver/views/scheduled_messages.py

@@ -3,18 +3,15 @@ from django.http import HttpRequest, HttpResponse
 from zerver.actions.scheduled_messages import delete_scheduled_message
 from zerver.lib.request import has_request_variables
 from zerver.lib.response import json_success
-from zerver.models import ScheduledMessage, UserProfile
+from zerver.lib.scheduled_messages import get_undelivered_scheduled_messages
+from zerver.models import UserProfile
 
 
 @has_request_variables
 def fetch_scheduled_messages(request: HttpRequest, user_profile: UserProfile) -> HttpResponse:
-    scheduled_messages = ScheduledMessage.objects.filter(
-        sender=user_profile, delivered=False, delivery_type=ScheduledMessage.SEND_LATER
-    ).order_by("scheduled_timestamp")
-    scheduled_message_dicts = [
-        scheduled_message.to_dict() for scheduled_message in scheduled_messages
-    ]
-    return json_success(request, data={"scheduled_messages": scheduled_message_dicts})
+    return json_success(
+        request, data={"scheduled_messages": get_undelivered_scheduled_messages(user_profile)}
+    )
 
 
 @has_request_variables