Contact model

This is a proxy class for describing relationships between users and can best be understood through an example.

The columns are labled in a confusing manner:

• A contact has a user, that is you and the perspective we're using from now on.
• A contact has a person that is the other entity in the relationship.
• A connection is thus modelled through two contacts, stored in the database that the user belongs to (can be the same one for local connections). receiving means that the person is receiving posts from the user, given the person can see them (public or matching an aspect_membership).
• sharing is a pure indicator if the person is sharing with the user.

Given we have userA with personA and userB with personB we can have the following situations.

• No contacts at all or contacts with receiving = 0 and sharing = 0: Users do not follow or share with each other.
• contactAB with receiving = 1 and sharing = 0: Then we have contactBA with receiving = 0 and sharing = 1. userA is following personB, userB is not following personA.
• contactBA with receiving = 1 and sharing = 0: Then we have contactAB with receiving = 0 and sharing = 1. userB is following personA, userA is not following personB.
• contactAB with receiving = 1 and sharing = 1: Then we have contactBA with receiving = 1 and sharing = 1. A fully bi-directional relationship, both users are following each other.

Following and sharing are synonym terms, their perspective is just a little bit different.