The Power BI REST API returns an “Internal Server” error

[AnoukGorris]

When filters are used, the Power BI REST API returns an “Internal Server” error, instead of the data we are requesting. Even in cases when the REST API doesn’t fail, using filters significantly slows down the response from the server. When customer data is sufficiently large, the processing on Microsoft side is slowed down so much, that it exceeds some kind of their internal timeout, and an error is returned.
We know Microsoft has released new Power BI APIs, but we need time to switch to them. In the meantime, it is important that the filter works again.

[v-chuncz-msft]

@AnoukGorris 

I cannot reproduce it. Try it again and share more detailed information if possible.

[AnoukGorris]

Hi again,

This problem was reproduced by many of our customers who have a lot of workspaces. Collibra is a partner of Microsoft so I can only report the problems our customers have.

The filters work fine with small amounts of data, but when there's a lot of data, using a filter begins to be noticeably slower than when the filter is not used. Customers have complained that using a filter actually prolongs the time it takes to fetch results (though it should be doing the exact opposite), so this is confirmed. And when there is a lot of data, it seems it just gets so slow that it hits some internal timeout and returns an error instead of results. Of course, we can't confirm that without looking into Microsoft's code, but this is our best guess right now.