Do not generate URL if event has no uid

event.ics

@@ -21,10 +21,11 @@ CLASS:PUBLIC
 DTSTART;TZID=Europe/Berlin:{{ event.eventdate | date: "%Y%m%d" }}T{{ event.eventdate | date: "%H%M%S" }}
 DTEND;TZID=Europe/Berlin:{{ event.eventend | date: "%Y%m%d" }}T{{ event.eventend | date: "%H%M%S" }}
 DTSTAMP:{{ event.eventdate | date: "%Y%m%d" }}T{{ event.eventdate | date: "%H%M%S" }}Z
+{%- if event.uid %}
 {%- assign post = site.posts | where: "uid", event.uid | first %}
 {%- if post %}
 URL:{{site.url}}{{post.url}}
-{%- endif %}
+{%- endif %}{%- endif %}
 END:VEVENT
 {%- endfor %}
 END:VCALENDAR

events.ics

@@ -21,10 +21,11 @@ CLASS:PUBLIC
 DTSTART;TZID=Europe/Berlin:{{ event.eventdate | date: "%Y%m%d" }}T{{ event.eventdate | date: "%H%M%S" }}
 DTEND;TZID=Europe/Berlin:{{ event.eventend | date: "%Y%m%d" }}T{{ event.eventend | date: "%H%M%S" }}
 DTSTAMP:{{ event.eventdate | date: "%Y%m%d" }}T{{ event.eventdate | date: "%H%M%S" }}Z
+{%- if event.uid %}
 {%- assign post = site.posts | where: "uid", event.uid | first %}
 {%- if post %}
 URL:{{site.url}}{{post.url}}
-{%- endif %}
+{%- endif %}{%- endif %}
 END:VEVENT
 {%- endfor %}
 END:VCALENDAR