Add the possibility to skip dates for recurring events (#24)

* Loop through all except_on dates and remove them from recurrent event

Signed-off-by: Eduard Itrich <eduard@itrich.net>

* Fix CI errors

* Combine EXDATE into a comma seperated list

Signed-off-by: Eduard Itrich <eduard@itrich.net>

* Add time to EXDATE

* Add TZID to EXDATE if timezone is given

Author: itrich

example/test_calendar.yaml

@@ -33,6 +33,18 @@ events:
         weeks: 1
       until: 2022-12-31 # required
 
+  - summary: Recurring event with exception
+    begin: 2022-07-01 10:00:00
+    duration: {minutes: 60}
+    repeat:
+      interval:
+        # seconds, minutes, hours, days, weeks, months, years
+        hours: 4
+      until: 2022-07-31  # required
+      except_on:
+        - 2022-07-13
+        - 2022-07-14 06:00:00
+
   # All-day event
   - summary: Earth Day
     begin: 2021-04-22

tests/test_events.py

@@ -65,6 +65,33 @@ def test_rrule():
     assert "RRULE:FREQ=YEARLY;UNTIL=20300422T000000" in event_str
 
 
+def test_exception():
+    event = event_from_yaml(
+        parse_yaml(
+            """
+            summary: Recurring event with exception
+            timezone: America/Los_Angeles
+            begin: 2022-07-01 10:00:00
+            duration: {minutes: 60}
+            repeat:
+              interval:
+                hours: 4
+              until: 2022-07-31
+              except_on:
+                - 2022-07-13
+                - 2022-07-14 06:00:00
+            """
+        )
+    )
+    event_str = event.serialize()
+    # DTEND exists and is the next day, calendar tools import this
+    # correctly as being a one-day event
+    assert (
+        "EXDATE;TZID=/ics.py/2020.1/America/Los_Angeles:20220713,20220714T060000"
+        in event_str
+    )
+
+
 def test_event_with_time_range():
     event = event_from_yaml(
         parse_yaml(

yaml2ics.py

@@ -4,9 +4,9 @@
 
 CLI to convert yaml into ics.
 """
+import datetime
 import os
 import sys
-from datetime import datetime, tzinfo
 
 import dateutil
 import dateutil.rrule
@@ -25,7 +25,14 @@
 }
 
 
-def event_from_yaml(event_yaml: dict, tz: tzinfo = None) -> ics.Event:
+def strfexception(exdate):
+    if isinstance(exdate, datetime.datetime):
+        return datetime.datetime.strftime(exdate, "%Y%m%dT%H%M%S")
+    elif isinstance(exdate, datetime.date):
+        return datetime.datetime.strftime(exdate, "%Y%m%d")
+
+
+def event_from_yaml(event_yaml: dict, tz: datetime.tzinfo = None) -> ics.Event:
     d = event_yaml
     repeat = d.pop("repeat", None)
     if "timezone" in d:
@@ -90,7 +97,28 @@ def event_from_yaml(event_yaml: dict, tz: tzinfo = None) -> ics.Event:
             )
         )
 
-    event.dtstamp = datetime.utcnow().replace(tzinfo=dateutil.tz.UTC)
+        if "except_on" in repeat:
+            exdates = map(
+                lambda exdate: strfexception(exdate),
+                repeat["except_on"],
+            )
+            if tz:
+                event.extra.append(
+                    ics.ContentLine(
+                        name="EXDATE",
+                        params={"TZID": [str(ics.Timezone.from_tzinfo(tz))]},
+                        value=",".join(exdates),
+                    )
+                )
+            else:
+                event.extra.append(
+                    ics.ContentLine(
+                        name="EXDATE",
+                        value=",".join(exdates),
+                    )
+                )
+
+    event.dtstamp = datetime.datetime.utcnow().replace(tzinfo=dateutil.tz.UTC)
     if tz and event.floating and not event.all_day:
         event.replace_timezone(tz)
     return event