Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

The Power BI Data Visualization World Championships is back! Get ahead of the game and start preparing now! Learn more

Reply
paulo_zip
New Member

Using Web.Contents with No Authorization header

Hi Everyone.

I'm creating a custom connector for Power BI using Power Query/M Language on Visual Studio. In the final step of my connector, it will use Web.Contents() to retrieve a presigned file in Amazon S3.

 

Since it's a presigned file, my request CAN NOT have an Authorization Header, otherwise, it will return an error. The problem is that I'm not able to make the following call without Authorization header:

 

results = Web.Contents(file_download_url)

I know that the function Web.Contents() have an Authorization parameter, so I could use something like:

 

results = Web.Contents(file_download_url, [Headers = [Authorization = "ANYTHING HERE"]])

However, I can't pass an empty Authorization parameter. If I use the default value, it will send a Basic Authorization, which will not work, due to the presigned file won't return with an Authorization header.

 

One interesting thing to notice is that, if I copy the file URL and paste it into Power BI, it works, because Power BI doesn't send Authorization header on the request (I've double-checked it using Fiddler).

 

Does anybody know how to send a request without the Authorization header?

1 REPLY 1
Jayendran
Solution Sage
Solution Sage

Hi @paulo_zip ,

 

Can you try the null. For a quick sample I tried the below it's worked for me

let
Source = Table.FromColumns({Lines.FromBinary(Web.Contents("https://testik.free.beeceptor.com/my/api/path"), null, null, 1252)})
in
Source

 

Helpful resources

Announcements
November Power BI Update Carousel

Power BI Monthly Update - November 2025

Check out the November 2025 Power BI update to learn about new features.

Fabric Data Days Carousel

Fabric Data Days

Advance your Data & AI career with 50 days of live learning, contests, hands-on challenges, study groups & certifications and more!

FabCon Atlanta 2026 carousel

FabCon Atlanta 2026

Join us at FabCon Atlanta, March 16-20, for the ultimate Fabric, Power BI, AI and SQL community-led event. Save $200 with code FABCOMM.

Top Kudoed Authors