Retrieving the user profile data depends on the API of the site you want to access. Usually you need to send an HTTP request to the API using a token retrieved by this class using the OAuth protocol. You need to use the CallAPI function for that purpose.
Most examples show exactly what is the API URL you need to call to get the user profile. Take a look at the respective example script.
The redirection process is necessary to get the OAuth token, so the class can call the API with the permission of the user. The redirection target page is usually a page on which the user is prompted to give your application permission to access his profile. So you cannot skip this step.
Read this article for more details:
phpclasses.org/blog/package/7700/po
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