Triggered twice - When an event is added, updated or deleted (V3)

[Power_Robert]

Hi,

When an event is created (via OWA) in a calendar, the "When an event is added, updated or deleted (V3)" event is triggered twice.

See image below:

The only real difference there is, is the value of "x-ms-apihub-cached-response". (Can't find much info about this.)

I created an extra condition in the flow to catch the version with value "false" and terminate the flow when the value is "true".
This is not reliable. While testing, the event was triggered twice again where both had "true" as value.

Why is it triggered twice? Is this a bug?

How can you make a reliable flow with this trigger?

Thank you!

[JohnAageAnderse]

Hello @Power_Robert 

I just tested using my own calendar and a test flow that uses the same trigger as your flow.

I created an event and the flow was triggered once.

Is there anything special about your calendar that your flow triggers on?

Is there another flow that triggers on the calendar events and does it perform an update?

Kind regards, John

[ericwhitley]

The duplicate triggers for New Events (ActionType = "added") is one of many bugs with this connector.  In my case it happens about 20% of the time and the "Date" value is always exactly the same.  This connector no longer has the "lastModifiedDateTime" property that you show above (I'm running this in July 2022) so there's no way to tell which is more recent.

What's worse is the "id" property is different on the duplicate triggers so we can't use that to compare values.  Luckily the "iCalUId" property remains the same.

[drkmccy]

I was having similar issues so I created a new flow with this trigger and followed it with a compose which had "Subject - ActionType"

I added an event:

Then I changed the subject, triggering the flow twice. Once with the old subject and once with the new subject:

So it is a bug in a way as the first update trigger is not the actual update, it's what it was before the update. Then the second trigger is after the update.

[dkuropka]

How is it possible that the bug is not fixed until now (2024)? I've made my first simple power automate job to sync calendars and I'm getting double entries... So in this case I'm afraid to use this for any more complicated needs.

[ericwhitley]

The first thing you can do is turn off the Split option, which let's you handle multiple incoming events simultaneously.  

Then you can filter the events by the iCalUId and process similar events concurrently.  Including the ability to ignore/skip one of the updates.

The real problem is the "id" property of each event can change, and then change back to its original value.  So it's best to keep a list of all id's for a particular event stored in your SP item.  Also, you can't always count on searching by this id to find the matching sp item, so you may have to search by organizer and date/time or subject.

Overall this is a huge headache and some duplicate items will always get through.  I added a check at the end of the process to look for duplicates and delete them if needed.