This is best Fabric, Power BI, SQL and AI community event. How do we know? The last event sold out! Save €200 with code FABCMTY200.
Register nowA new Data Days event is coming soon! This time we’re going bigger than ever. Fabric, Power BI, SQL, AI and more. Don't miss out.
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?
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
Check out the May 2026 Power BI update to learn about new features.
Sign up to receive a private message when registration opens and key events begin.
If you have recently started exploring Fabric, we'd love to hear how it's going. Your feedback can help with product improvements.