Custom Data Connector / How to troubleshoot Testconnection Handler

[sylbae-a]

Hello,

I built my first custom data connector (encapsulate access to authenticated Rest API).

It works fine with Power BI Desktop but I cannot enable scheduling of data source refresh through Enterprise Gateway.

I am pretty sure this is because of incorrect implementation of mandatory TestConnection handler.

When trying to configure the data source from Power BI web portal, I am getting an error "Cannot be added to gateway". In documentation, it is highlighted we likely have a problem with TestConnection if getting this message.

I developped my handler based on documentation:

https://docs.microsoft.com/en-us/power-query/handlinggatewaysupport

But cannot figure out the problem... Is there any logfile I could access to get further details ?

TestDataSource = [

    TestConnection = (dataSourcePath) => {"TestDataSource.Feed", dataSourcePath},

    Authentication = [

        UsernamePassword = []

    ],

    Label = Extension.LoadString("DataSourceLabel")

];

[Anonymous]

I'm in the same situation. If you guys find anything, please help. I'll do the same.

[john_dawson]

 I'm having related difficulties too; sorry, no answer, but a few resources that might be useful

The most useful (to me) was: https://docs.microsoft.com/en-us/power-query/handlinggatewaysupport, which covers parameters, which is perhaps a common problem with TestConnector; it is necessary that your TestConnector is called with the right parameters, otherwise it will fail

This is also useful: https://docs.microsoft.com/en-us/power-query/samples/trippin/9-testconnection/readme; as it says, unfortunately, there is no way to test TestConnection except in the On-premises Data Gateway, which makes it hard to track down problems

I'll come back if I myself make useful progress

[sylbae-a]

Ultimately I troubleshooted my problem reviewing my code. But as a generic need, I still think it would be a good idea to implement some logging on the gateway. That would be very helpful

[Anonymous]

Hi @sylbae-a , I'm encountering the same issue. Could you please share how you solved this? My custom connector works fine in desktop but I cant get it to work through the gateway. I am able to enter credentials (Oauth2) but after the oauth flow the data source sign in window stays opened, nothing happens. I think it is caused by the testconnection configuration but I'm not able to find the exact cause.