translytical-task-flow button not working?

Hi paulos​,

The replies above are pointing in the right direction. One thing I would clarify from Microsoft’s current documentation is the exact sequence in which the parameters appear.

The parameter mappings do not show just because the button Action is set to Data function.

You first need to select the actual published User Data Function:

Button
→ Action = Data function
→ select the fx button next to Data function
→ OneLake catalog opens
→ select the published function

After that, Power BI displays the Workspace, Function set and function name, and then the parameters from that function appear for mapping.

Microsoft documents that flow in the Data function button guidance.

Also check that the User Data Function returns a string. Microsoft specifically requires a function used by a Power BI data-function button to return a str value.

So I would test with the smallest possible function first, for example:

import fabric.functions as fn

udf = fn.UserDataFunctions()

@udf.function()
def hello(name: str, amount: int) -> str:
return f"Received {name}, {amount}"

Publish that function, select it from the button’s OneLake catalog, and confirm whether name and amount then appear.

If they do, the button configuration is fine and the issue is inside the original function definition.

One other current limitation to be aware of: you can configure the button in Power BI Desktop, but Microsoft notes that the action itself cannot be triggered until the report is published to the Service.

There is also now a dedicated Data function button option in the newer translytical task-flow tutorial, so I would use that rather than relying only on a generic blank button where possible.

Microsoft’s current end-to-end tutorial walks through the same sequence.

So my troubleshooting order would be:

published function
→ return type is str
→ select function from OneLake catalog
→ confirm parameters appear
→ map parameters
→ publish report
→ test execution in the Service

If the parameters still do not appear after a valid published function is selected, then I would treat that as unexpected behavior rather than just a missing configuration step.

AI-assisted drafting: AI was used to help structure and phrase this response. I reviewed and validated the technical content before posting.