CHECK USER EXISTANCE

This service allows Virtualnewspaper to verify if an user exists on an external platform

An user try to log-in on a VirtualNewsaper platform and his account is NOT in the db.
VirtualNewspaper needs to check the external platform.

The external platform has to provide a WS to be consulted.
VirtualNewspaper send the "email" parameter to the external platform and awaits for the answer

The external platform WS must answer using a Json

CASE #1
email exists:

{
exists:true
}

CASE #2
email does not exist:

{
exists:false
}

If is the CASE #1: the user exists in the external platform.
The user is stopped by the Virtualnewspaper to avoid a double registration and he is invited to log-in.
When he tries to log-in using the login ws the user will be logged-in and his datas synchronized

In CASE #2: the user does not exist in the VirtualNewspaper neither in the external platform.
The user can complete his registration and datas collected by Virtualnewspaper will be synchronized using the User registration Output ws