Ruby on Rails: Add subfolder in app directory with files specific to models

Question

I am writing a gem which will handle all kind of notifications for a model (sms, mobile and browser notifications)

in rails project under app directory created new folder 'notifiers' which contain files like

app/notifiers/user_notifier.rb

class UserNotifier < ApplicationNotifier
  def send_reminder
   {
     type: 'sms',
     content: 'hi everyone',
     recipients: [12134343,2342322,3434343]
   }
  end
end

this user_notifier file should be against User model. means that this method send_reminder should be available to instance/object of User

User.last.send_reminder So, issue is

• how to make files of notifiers folder to model specific (user.rb model file has user_notifier.rb file in notifiers folder)
• how this file user_notifier.rb methods would be available to user model

This is possible with concerns and namespaces but this would create messy code

Answer 1

Thanks to Léonard, he posted the solution but while writing the gem we need to handle these configuration from gem. Because when someone use our gem he/she don't have to write any configuration related logic in application_record.rb manually.

posting it just to ensure that in future may it helpful for someone else.

what i did to tackle this issue (to attach gem with a model we add act_as_notifier in model with which we want it to be configured)

• In model_config.rb class of notifier gem
• Have @model_class & find corresponding notifier class
• Add attr_accessor in notifier class and initialize it with model object
• Also define custom getter and setters notifier attribute

#rails_notifier/model_config.rb
    def initialize(model_class)
      @model_class = model_class
      
      # get model corresponding notifier class
      # for User model class, there would UserNotifier class
      # under notifiers folder of app directory
      # getting notitifer class name
      notifier_class = "#{@model_class.name}Notifier"
      
      # Notifier class attribute set later set with model object
      attribute_name = @model_class.name.underscore
      
      # register a `notifier` method in model class
      # 'method_name' is a method of notifier class
      # and options hash contain sender
      @model_class.class_eval do
        define_method(:notifier) do |method_name, options|
          # create notifier class object
          notifier_ = notifier_class.constantize.new

          # define setter for notifier attribute
          notifier_.send(:define_singleton_method, "#{attribute_name}=".to_sym) do |value|
            instance_variable_set("@" + attribute_name.to_s, value)
          end

          # define getter for notifier attribute
          notifier_.send(:define_singleton_method, attribute_name.to_sym) do
            instance_variable_get("@" + attribute_name.to_s)
          end

          # self point to the object of model
          # e.g User.last.notifier(:send_reminder), slef = User.last
          # set notifier attribute with model object
          notifier_.send("#{attribute_name}=".to_sym, self)
          notifier_hash = notifier_.send(method_name)
          RailsNotifier.notify(notifier_hash) if notifier_hash.present?
        end
      end
    end