Viewing large pdf files from SharePoint in browser anonymously(no login)

Question

Hello,
I have a SharePoint online document library which contains large PDF documents which are more than 200mb.

I have a MVC application which will show these PDF documents from SharePoint. Currently in the code, I'm downloading the entire document in memory and opening in the browser.
This takes time to show even the first page as it need to download the entire file in the memory. I need to load these documents for users who do not have access to SharePoint.

This works well if I directly open the SharePoint file URL and it is streaming the files (loading the first few pages instantly). But this requires logging in to the SharePoint site.

My company policy doesnt allow me to generate the anonymous file URL.

I know there is an option to generate the temporary file download URL for the documents in SharePoint library using Graph API by passing some token.

Is there any other option similar to this available to show the document view page in the browser by passing the token?

Or Is there any other option available which can solve my problem?

Thanks in advance.

Thanks,
Jawahar

Answer 1

Hi @jawahar ks
Per my research, I would recommend you to grant access using use SharePoint app only. Then you can get access token by the app only.
Here is the document about SharePoint app only
https://learn.microsoft.com/en-us/sharepoint/dev/solution-guidance/security-apponly-azureacs

Please refer to the following steps to get an access token
https://global-sharepoint.com/sharepoint-online/in-4-steps-access-sharepoint-online-data-using-postman-tool/

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Answer 2

Hi @RaytheonXie_MSFT ,

Thanks for the answer. Using the SharePoint app with the token, I can perform other operations like accessing list, add/edit items.
But is it possible to load document view URL with the token?

Thanks,
Jawahar