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Hello,
This might be an old question but maybe changes/updates have changed the answer.
Based on some articles below - it looks like dax function CustomData(https://docs.microsoft.com/en-us/dax/customdata-function-dax) will retrieve the CustomData property of the connection string in SSAS on premise.
https://www.kasperonbi.com/using-customdata-and-ssas-with-power-bi-embedded/
SSRS passes the {{USERID}} values into the connection string on connection - does PBIRS function the same way when an authenticated user opens a report with CustomData={{USERID}} in the connection string on the report server webpage?
If there any particular function or method found in the custom forms authentication example on github that would be crucial to the resolution of this value? Would SSRS or PowerBIRS be invoking GetUserInfo()?
Oh wow! This is highly interesting. We are investigating on how to deploy federated login to SSRS and with this we could transfer the signing account info all the way to SSAS to filter the data.
Thank you for confirming this works!
I'm confirming this is working.
Dax function CustomData() is returning {{USERID}} parameters from the report connection string set up in PBIRS.
Some marked solutions in the forum are giving incorrect information.
The finding above means you can implement a dax filter using CustomData() to acheive row level security to live connected SSAS on premise while authenticating users using an implementation like the custom security sample.
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