Add rotation ID fallback for ical events

engine/apps/schedules/ical_utils.py

@@ -367,6 +367,9 @@ def parse_event_uid(string):
         match = RE_EVENT_UID_V1.match(string)
         if match:
             _, _, _, source = match.groups()
+        else:
+            # fallback to use the UID string as the rotation ID
+            pk = string
 
     if source is not None:
         source = int(source)

engine/apps/schedules/tests/test_ical_utils.py

@@ -78,3 +78,11 @@ def test_parse_event_uid_v2():
     pk, source = parse_event_uid(event_uid)
     assert pk == pk_value
     assert source == "slack"
+
+
+def test_parse_event_uid_fallback():
+    # use ical existing UID for imported events
+    event_uid = "someid@google.com"
+    pk, source = parse_event_uid(event_uid)
+    assert pk == event_uid
+    assert source is None