[BUG] New-PnPSiteFileVersionExpirationReportJob does not work with managed identity

[bansalanshuman]

Description

I am trying to create a SPO site file version expiration report job using an Azure Function that uses a managed identity.
The Connect-PnPOnline command works fine, but when I run New-PnPSiteFileVersionExpirationReportJob it fails.

Error Message

It throws the below error:

NFORMATION: System.Management.Automation.PSInvalidOperationException: Cannot call this API with an app-only principal.
at PnP.PowerShell.Commands.Base.PnPConnectedCmdlet.ProcessRecord() in c:\build\src\Commands\Base\PnPConnectedCmdlet.cs:line 101
at PnP.PowerShell.Commands.PnPSharePointCmdlet.ProcessRecord() in c:\build\src\Commands\Base\PnPSharePointCmdlet.cs:line 121
at System.Management.Automation.Cmdlet.DoProcessRecord()
at System.Management.Automation.CommandProcessor.ProcessRecord()

Also, my requirements.psd1 has this entry:
'PnP.PowerShell' = '2.12.0'

Expected behavior

I should be able to generate the reports using managed identity if I am able to connect to the site.

Actual behavior

The command fails with the error above (Cannot call this API with an app-only principal.).

Steps to reproduce behaviour

Create an Azure function app, enable identity and then grant rights to the app(I have Sites.FullControl.All), then create a simple http triggered function and connect the site using command Connect-PnpOnline
run the command New-PnPSiteFileVersionExpirationReportJob

What is the version of the Cmdlet module you are running?

(you can retrieve this by executing Get-Module -Name "PnP.PowerShell" -ListAvailable)

Which operating system/environment are you running PnP PowerShell on?

• Windows
• Linux
• MacOS
• Azure Cloud Shell
• [X ] Azure Functions
• Other : please specify

[reshmee011]

Is it possible for you to try same using the latest PnP PowerShell module which is 3.1.0 or even better with the latest nightly version?

[bansalanshuman]

I have tried them, what I have understood is the underlying commands do not support authentication via an app, if someone wants to use these commands they have to authenticate via a username and pwd

[reshmee011]

The error specified same, it will be up to Microsoft to update the behaviour to allow app only authentication. Have you tried it outside of Azure function using client id?

[bansalanshuman]

Yes I have tried it, it works as expected there, but as a part of automation and cloud only solution this was a huge setback.

[reshmee011]

Probably we need to update the documentation to reflect this limitation. Is it possible for you to raise with Microsoft to enable it in the background through the CSOM endpoint? I can't see it's possible to achieve through Graph API which could have been a solution.