Actors

In ContactHub, there are two primary types of actors involved in the sharing of contact information: users and servers. Users are individuals who utilize the service to store and share their contact information, while servers are the decentralized instances hosting the user data and facilitating communication.

Here is an example of the ActivityPub schema for a ContactHub user's "Person" actor:

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Person",
  "id": "https://example.com/user/username",
  "name": "John Doe",
  "preferredUsername": "username",
  "inbox": "https://example.com/user/username/inbox",
  "outbox": "https://example.com/user/username/outbox",
  "followers": "https://example.com/user/username/followers",
  "following": "https://example.com/user/username/following",
  "url": "https://example.com/user/username",
  "manuallyApprovesFollowers": true
}

User (Person Actor)

Users are represented as "Person" actors in the ActivityPub protocol. Each user has a unique identifier (id) in the format https://example.com/user/username. A user's "Person" actor includes several important properties, such as inbox, outbox, followers, and following. In ContactHub, we also set the manuallyApprovesFollowers property to true, which ensures that the user must explicitly approve or reject follower requests, enhancing privacy.

Followers and Following

In ContactHub, the followers and following properties serve a different purpose than in traditional social media platforms. Instead of representing a social connection, these properties indicate the users with whom contact information can be shared or requested.

When a user (User A) follows another user (User B), User A is requesting access to User B's contact information. User B must approve this request for User A to become a follower. Once approved, User A will be able to access User B's shared contact information. In this context, the followers property represents the users who have been granted access to the user's contact information, and the following property represents the users whose contact information the user can access.

Server

Servers in ContactHub are instances that host user data and implement the ActivityPub protocol to facilitate communication between users. Each server has its own domain and can interact with other servers in the network. Servers handle activities such as storing and retrieving contact information, processing incoming and outgoing ActivityPub messages, and managing user authentication and authorization.

By using a federated architecture, ContactHub allows users to choose their preferred server or even host their own server to maintain control over their data. This decentralization helps ensure user privacy and prevents a single point of failure or data breach.

For more information on the various activities and objects used in ContactHub, refer to the Activities and Objects documentation.