Triggering a flow if a Person/Group column has been modified

[faschimi]

Hello all,

I am setting a flow to grant permissions on a Sharepoint Online file library. I customize a document set content type and added two Person/Group fields, "SME" and "Instructor", that must be defined for every document set before uploading the files. When the files are uploaded, they automatically inherit the values of fields defined in the document set.

So, I need to grant edit permissions to the user(s) defined in "SME" field and view permissions to the user(s) defined in "Instructor" field. I was able to do that setting a trigger when a file is uploaded. But I also need to run the flow in case the fields "SME" and "Instructor" are modified after some time even if the file is not updated.

How can I set a trigger in this condition? Is there a way to monitor if only the "SME" and/or "Instructor" fields have changed?

[faschimi]

I might found the answer as explained in this video about the "Get changes for an item or a file (properties only)" feature: https://www.youtube.com/watch?v=AaWB3xlhJdc

I tried to replicate the same steps, but I got a BadGateway error:

{

  "error": {

    "code": 502,

    "source": "brazil-001.azure-apim.net",

    "clientRequestId": "72b01636-6d9a-4879-a1b9-012015e83b2b",

    "message": "BadGateway",

    "innerError": {

      "status": 500,

      "message": "Index was out of range. Must be non-negative and less than the size of the collection.\r\nParameter name: index\r\nclientRequestId: 72b01636-6d9a-4879-a1b9-012015e83b2b\r\nserviceRequestId: 72b01636-6d9a-4879-a1b9-012015e83b2b"

    }

  }

}

What am I missing?

[v-bofeng-msft · Accepted solution]

Hi @faschimi ,

If you want to check whether a field is changed or not , you could try this solution:

Best Regards,

Bof

[faschimi]

Thank you Bof! This approach, using version number, has worked for me.

[faschimi]

I need to reopen this topic because I am facing a BadRequest error, this time the error message is "Specified Version Label does not correspond to any actual version":

I don't know if I understand this right, but this flow shouldn't run when a file is at version 1.0, because there will be no version "0.0" to compare to. Is there any way to prevent the flow from executing in this condition?