Module sc_utils::pubsub

Provides means to implement a typical Pub/Sub mechanism.

This module provides a type Hub which can be used both to subscribe, and to send the broadcast messages.

The Hub type is parametrized by two other types:

• Message — the type of a message that shall be delivered to the subscribers;
• Registry — implementation of the subscription/dispatch logic.

A Registry is implemented by defining the following traits:

• Subscribe<K>;
• Dispatch<M>;
• Unsubscribe.

As a result of subscription Hub::subscribe method returns an instance of Receiver<Message,Registry>. That can be used as a Stream to receive the messages. Upon drop the Receiver<Message, Registry> shall unregister itself from the Hub.

Structs

• Hub
  A subscription hub.
• Receiver
  The receiving side of the subscription.

Traits

• Dispatch
  Dispatch a message of type M.
• Subscribe
  Subscribe using a key of type K
• Unsubscribe
  Unsubscribe: unregisters a previously created subscription.