Trigger action in Rails controller on model callback

Question

I am trying to wrap my head around Live Streaming with Server-Sent Events in Rails. I have a Rake task listening for file changes which adds records to the database. Once added I would like to send a SSE to the frontend.

But, the model can't send events to the frontend, the controller is responsible for that. How do I tell my controller a new record was added to the database?

My (broken) solution so far: use an EventBus with an after_save callback in the model that announces the changes and asks the controller to listen for these messages:

require 'reloader/sse'
class SseController < ApplicationController
  include ActionController::Live

  def index
    response.headers['Content-Type'] = 'text/event-stream'
    sse = Reloader::SSE.new(response.stream)
    EventBus.subscribe(:added) do |payload|
      sse.write({ /* payload */ })
    end
  rescue IOError
  ensure
    sse.close
  end
end

I think my request ends before the event is received meaning it will never end up in de subscribe block. Is this the right approach, if so, what am I missing?

Answer 1

SOLN 1: you can use rest_client gem to send a request to your controller in your after_save callback from model.

SOLN 2: Why dont you call a model method in your controller which creates the database records and then handles further action based on whether record was created or not