Variables with blank kusto source

Hi all,

i'm new to Power BI. I have a data source that is a Kusto query that extract data from an ApplicationInsight db.

Is there a way to customize the AppInsight repo url inside the blank query?

I've tryed with parameters this way:

1) create a param with the appInsight repo url:

appRepo = www.blablabla.com

2) in the advanced query editor, i've changed the row:

let Source = Json.Document(Web.Contents(" .... the url source ... ",

with

let Source = Json.Document(Web.Contents("&appRepo&",

..... but no luck!!! I receive an URI parse error!!!

Thanks