pubsub

example.rb

class User < ActiveRecord
  include Pubsub::Publisher
  
  after_create do
    publish(:welcome, user_name: name)
  end
end

class Post < ApplicationRecord
  include Pubsub::Publisher
  belongs_to :user
  
  after_create do
    publish(:create_post, user_name: user.name, title: title, image_url: user.image_url)
  end
end

class SlackNotifier
  include Pubsub::Subscriber
  use :slack, channel: '#general', username: 'angel', icon_emoji: ':innocent:'

  subscribe :User, :Post
  
  def welcome(context)
    notify_success("#{context[:user_name]} has joined.")
  end
  
  def create_post(context)
    notify_info("#{context[:user_name]} has create post of #{context[:title]}.", icon_url: context[:image_url])
  end
end