I am working in SharePoint Online.
I am trying to make a SharePoint SPFX webpart that :
Will be added to a modern page in some site collection, let's call it SiteA
Will read the contents of a document library from another site collection, let's call this other site SiteB
A user that has read access to SiteA, but no access rights to SiteB, should be able to navigate to the modern page with the webpart in SiteA, and while allowing the application to access the contents of the document library residing in SiteB.
Anyone have any suggestions on how this could be achieved? Is there a way of achieving this purely in SharePoint (without registering an app in Azure AD, or making a Web service that will access the off-limits site that the signed-in user doesn't have access to)?
Any way of giving read permissions to individual sites to the SP app that contains the WebPart?