Power BI keeps loading when connecting to a REST API

[SabaAbuarar9]

Hello,

I am experiencing an issue while connecting Power BI Desktop to a REST API.

The API works successfully in Postman; however, it takes approximately 2 minutes to return the response. When I use the same API in Power BI, the request keeps loading indefinitely, and after some time the process appears to restart instead of completing the import.

The API returns approximately 5 MB of XML data.

I have verified the following:

The API endpoint is correct.

Authentication is successful.

The API returns the expected data in Postman.

The issue only occurs when the API is consumed by Power BI.

Has anyone encountered a similar issue? Is there a timeout limit or a recommended approach for consuming slow REST APIs in Power BI?

Any guidance would be greatly appreciated.

Thank you.

[v-sathmakuri]

Hi @SabaAbuarar9 ,

Could you please review the suggestion provided above and let us know if you still have any further questions?

Thanks!!

[v-sathmakuri]

Hi @SabaAbuarar9 ,

Thank you for reaching out to fabric community.

• Since your API takes around 2 minutes to respond, it may be hitting Power Query's default Web.Contents timeout (about 100 seconds). If you're using Web.Contents, try increasing the timeout using the Timeout option as below

Web.Contents(
"https://your-api-url",
[Timeout = #duration(0, 0, 5, 0)]
)

• If the API supports pagination or filtering, try reducing the amount of data it returns
• Check Power Query Diagnostics (Tools → Start Diagnostics) to determine whether the request is timing out, being retried, or failing for another reason.

Thanks!!

[SabaAbuarar9]

Thank you for answering my question.

This approach worked. However, I noticed something unusual: it didn't appear to send the request to the API I created, yet the data loaded almost instantly. This is strange because the same API takes around two minutes to respond in Postman.

Could you please explain why this might be happening?

[v-sathmakuri]

Hi @SabaAbuarar9  , 

Glad to hear it worked.

If the data loaded almost instantly and your API didn't receive a new request, Power BI may have returned a cached response instead of calling the API again. Power Query caches requests during development to improve performance. To verify try refreshing the preview, clearing the Power BI cache, or making a small change to the request (such as adding a dummy query parameter) and see if the API is called again.

Cache clearing in power bi desktop : Troubleshoot Power BI Desktop publishing - Power BI | Microsoft Learn 

If it still doesn't reach your API, please let us know whether you are refreshing the Power Query preview or performing a full dataset refresh as the behavior can differ.

Thanks!!