Ash.Resource extension for defining event dispatching and counter broadcasting.

This extension adds dispatch and counters sections to Ash resources, allowing you to define events and counters that are triggered by resource actions.

Event Dispatching

defmodule MyApp.Orders.ProductOrder do
  use Ash.Resource,
    extensions: [AshDispatch.Resource]

  actions do
    create :create_from_cart do
      # ... action logic ...
    end
  end

  dispatch do
    event :created,
      trigger_on: :create_from_cart,
      channels: [
        [transport: :in_app, audience: :user],
        [transport: :email, audience: :user, delay: 300]
      ],
      content: [
        subject: "Order created",
        notification_title: "Order created"
      ]
  end

  counters do
    counter :pending_orders do
      trigger_on [:create_from_cart, :cancel]
      counter_name :pending_orders
      audience :user
      invalidates ["orders"]
    end
  end
end

Complex Events

For events that need custom logic, reference a callback module:

dispatch do
  event :created,
    trigger_on: :create_from_cart,
    module: MyApp.Events.OrderCreated
end

The callback module implements AshDispatch.Event behaviour.

Auto-Injection

The extension automatically injects changes into actions:

• DispatchEvent for events specified in dispatch section
• BroadcastCounterUpdate for counters specified in counters section

You don't need to manually add these changes.

Features

• Inline definitions - Simple events/counters defined in the resource
• Auto-injection - Changes automatically added to actions
• Type safety - Compile-time validation of configurations
• Optional complexity - Use callback modules when needed