CallBack represents a callback object with the necessary fields for a subscriber to receive updates.

MessageBroker is the main object which holds the subscribers and publishers.

Publisher represents a publisher object that contains a unique identifier and the name of the channel it publishes to.

Response is a struct for responses with a status code, message, and data.

Subscriber represents a subscriber object with a callback and channel Subscriber is a client that subscribes to a channel to receive updates via its CallbackUrl endpoint.

Updates represents an update object, containing information about the publisher and the message to be published.