✨ introduce max search horizon config

Adds `MAX_SEARCH_HORIZON` environment variable to control the
maximum range of days for search operations.

Splits longer search periods into multiple requests, preventing
potential performance issues or timeouts with large datasets.

docker-compose.yaml

@@ -16,6 +16,7 @@ services:
       - SMTP_SERVER=your.smtp.server # adjust this
       - SMTP_PORT=587 # adjust this if necessary
       - SMTP_SENDER_NAME=Room Booking System # adjust this if you want
+      - MAX_SEARCH_HORIZON=14 # adjust maximal range of days (longer search periods will get split into multiple requests)
 
 volumes:
   app-data:

src/clear_bookings.py

@@ -12,10 +12,12 @@ from pprint import pprint
 
 import caldav
 import pytz
-from caldav import CalendarObjectResource, Principal, Calendar
+from caldav import CalendarObjectResource, Principal, Calendar, DAVObject
 from jinja2 import Template
+from django.core.exceptions import ObjectDoesNotExist
 
 tz = pytz.timezone(os.getenv("TIME_ZONE", "Europe/Berlin"))
+MAX_SEARCH_HORIZON = int(os.getenv("MAX_SEARCH_HORIZON", 14))
 
 class DavEvent:
     """
@@ -29,7 +31,7 @@ class DavEvent:
     created: datetime
     status: str
     organizer: str
-    calendar: Calendar
+    calendar: DAVObject
     obj: CalendarObjectResource
     missing_required_fields: list
 
@@ -119,11 +121,10 @@ class DavEvent:
         if match:
             token = match.group()
             print(f"Priority token found in event description: {token}")
+            try:
                 token_obj = PriorityEventToken.objects.get(token=token)
-
-            # Check if the token object exists in the database
-            if not token_obj:
-                print(f"Priority token '{token}' not found in database.")
+            except ObjectDoesNotExist:
+                print(f"Priority token could not be found in database: {token}")
                 return False
 
             # If token is already used, verify signature
@@ -263,17 +264,34 @@ def clear(target_calendars: list, is_test: bool=False) -> dict:
         print(f"--- Clearing cancelled bookings and overlaps in calendar: {calendar.id}")
         horizon = tcal_by_name[calendar.id].auto_clear_overlap_horizon_days
 
+        # Split horizon search into multiple requests if horizon is bigger
+        # than MAX_SEARCH_HORIZON
+        horizons = []
+        while horizon > 0:
+            if horizon >= MAX_SEARCH_HORIZON:
+                horizons.append(MAX_SEARCH_HORIZON)
+            else:
+                horizons.append(horizon)
+            horizon -= MAX_SEARCH_HORIZON
+
+        events_fetched = []
+        start_delta = 0
+        end_delta = 0
+        today = datetime.now(tz=tz).date()
+        for h in horizons:
+            end_delta += h
             try:
-            events_fetched = calendar.search(
-                start=datetime.now(),
-                end=date.today() + timedelta(days=horizon),
+                events_fetched.extend(calendar.search(
+                    start=today + timedelta(days=start_delta),
+                    end=today + timedelta(days=end_delta),
                     event=True,
                     expand=True,
                     split_expanded=True,
-            )
+                ))
             except Exception as e:
                 print(f"--- Failed to fetch events for calendar: {calendar.id}: {e}")
                 continue
+            start_delta += h
 
         # Create DavEvent objects from fetched events
         events = []
@@ -348,7 +366,6 @@ def clear(target_calendars: list, is_test: bool=False) -> dict:
                 elif not event.is_cancelled:
                     if not is_test:
                         event.cancel()
-                    is_cancelled = True
                     result["cancellation_type"] = "cancelled"
                     results["cancelled_overlapping_recurring_events"].append(result)
                     print("Cancelled overlapping recurring event:")