As of yet, Power BI can not query an API that uses authentication via a token added to the HTTP header. While this works when used in Power BI Desktop, the query crashes after uploading to powerbi.co...
'I'm having the same troubles. It works in power bi desktop, but I cannot set up auto refresh in power bi service. Data are extracted as follows: = Web.Contents("https://app.idoklad.cz/developer/api/IssuedInvoices?PageSize=1000000&Page=1",[Headers=[#"SecureToken" = "",#"X-App" = "iSmart",#"X-App-Version" = "1.0"]])
