Bound calendar recurrence expansion and retain MQTT license

pigway_frame_flow/providers/ical.py

@@ -50,6 +50,12 @@ def calendar_events(raw, now=None):
     for props, start, uid, override in parsed:
         if props.get("STATUS", [(None, "")])[0][1] == "CANCELLED":
             continue
+        if "EXRULE" in props:
+            raise FlowError(
+                E.UNSUPPORTED_CAPABILITY,
+                "Use EXDATE instead of unsupported EXRULE",
+                422,
+            )
         occurrences = [start]
         if "RRULE" in props and not override:
             rule = props["RRULE"][0][1]
@@ -63,9 +69,21 @@ def calendar_events(raw, now=None):
                 raise FlowError(
                     E.INVALID_REQUEST, "Calendar recurrence starts too far in the past"
                 )
-            occurrences = rrulestr(rule, dtstart=start).between(
-                now - timedelta(days=1), end, inc=True
-            )
+            if len(rule) > 1000:
+                raise FlowError(
+                    E.INVALID_REQUEST, "Calendar recurrence rule is too long"
+                )
+            occurrences = []
+            for occurrence in rrulestr(rule, dtstart=start).xafter(
+                now - timedelta(days=1), count=1001, inc=True
+            ):
+                if occurrence >= end:
+                    break
+                occurrences.append(occurrence)
+            if len(occurrences) > 1000:
+                raise FlowError(
+                    E.INVALID_REQUEST, "Calendar recurrence exceeds 1000 instances"
+                )
         for key, value in props.get("RDATE", []):
             occurrences.extend(stamp(key, item) for item in value.split(","))
         excluded = {