How to use access token during making GET Request to Sharepoint file?

i use sharepoint as cloud storage. I have a few .pdf files there now, and gave them public accessibility. So i'm available to open file by this url in anonymous window.

I need to use current files in another system (Salesforce), and i need to make api callouts to GET those files(base64).

I got access_token by this endpoint: https://accounts.accesscontrol.windows.net

Postman Request Image

This is file public url: https://lpnu-my.sharepoint.com/personal/marian_lyzhychka_mtrte_2021_edu_lpnu_ua/_layouts/15/onedrive.aspx?id=%2Fpersonal%2Fmarian%5Flyzhychka%5Fmtrte%5F2021%5Fedu%5Flpnu%5Fua%2FDocuments%2FWhoMovedMyCheese%281%29%2Epdf&parent=%2Fpersonal%2Fmarian%5Flyzhychka%5Fmtrte%5F2021%5Fedu%5Flpnu%5Fua%2FDocuments&ga=1

When i tried to send GET request to this endpoint and set received Access_token as bearer token, i received 401 (Unauthorized).

I am available to get file if i get cookie from developer tools, and set as header. But for every file cookies are different and it work's for me only for testing.

Could you please explain me what i do wrong? And how to access public files via request (JavaScript). Thank you!

Solution

According to my research and testing, when you generate the access_token, are permissions granted to the add-in, and what permissions are granted?

Please try granting Full Control permission, for example: enter the below XML in the “Permission Request XML” box:

<AppPermissionRequests AllowAppOnlyPolicy="true">
  <AppPermissionRequest Scope="http://sharepoint/content/tenant" Right="FullControl" />
</AppPermissionRequests>

If you want to get files in SharePoint, you can use the following Rest API:

GET https://{site_url}/_api/web/lists/GetByTitle('Test')/items
Authorization: "Bearer " + accessToken
Accept: "application/json;odata=verbose"

If you want to get a specific file, you can use the following REST API:

GET https://{site_url}/_api/web/lists/GetByTitle('Test')/items({item_id})
Authorization: "Bearer " + accessToken
Accept: "application/json;odata=verbose"

More information for reference:

Rest API: Working with lists and list items with REST

Generate access-token and access SharePoint: In 4 steps access SharePoint online data using postman tool

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