Using GAM Web Backoffice, or programmatically using the GAM API you can configure GAM Google Authentication Type (X Evolution 3 upgrade 3 and prior) or GAM Facebook Authentication Type (X Evolution 3 upgrade 3 and prior) and define in both cases an Additional Scope which gives the user access to resources of the site.
The scope is basically what APIs the application is trying to get access to.
In that sense, by using the Google API you can provide a web page in your application where the user can get his RSS feeds for example.
Other information he can access is the photos he has uploaded, e-mail contacts, files in google drive, etc.
So the purpose of this property is to allow to integrate the application with the information provided by Google and Facebook APIs, after the user has been logged in using GeneXus Access Manager Google or Facebook authentication type respectively.
Basically, after the user logs in, the session keeps an external token which can be used to access the Google or Facebook APIs.
Interact with Google APIs using GAM
Interact with Facebook APIs using GAM
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