It is often the case that there are certain parts of your web application that you don't want to be accessible to everyone, especially in the case of SaaS applications. That's where you need to guard certain functionalities or the entire application behind some sort of user management.
Google App Engine provides you with some really solid and strong user management out of the box. The process is pretty simple. The API is defined in the
google.appengine.api.users package. The whole package contains a total of four functions and a single
User class, which are as follows, and that's how the process works:
get_current_user(): This returns the current logged in user. This is an instance of the
Userclass, which we'll examine in a while. If this function returns
None, this means that nobody is logged in.
Now, in a case where nobody has logged in, we will have to serve them a login form. How do we do this? There's nothing that you have to do at your end. You just call