Useful application record snippet for rails application

application_record.rb

# frozen_string_literal: true

class ApplicationRecord < ActiveRecord::Base
  self.abstract_class = true

  # List all model classes
  def self.models
    @models ||= begin
      models = []
      Rails.root.join('app', 'models').glob('**/*.rb') do |path|
        model = path.relative_path_from(Rails.root.join('app', 'models')).to_s.sub(%r{\.rb$}, '').classify.safe_constantize
        models.push(model) if model && model < self
      end
      models
    end
  end

  # List reflection foreign columns
  def self.reflection_columns
    @reflection_columns ||= reflect_on_all_associations(:belongs_to).map(&:foreign_key)
  end

  # List actual attribute columns(without association columns)
  def self.attribute_columns
    @attribute_columns ||= columns.map(&:name) - reflection_columns
  end

  # List reflection classes
  def self.reflection_classes
    @reflection_classes ||= reflect_on_all_associations.map { |r| [r.name.to_sym, r.klass] }.to_h
  end

  # Translate association column name by model name
  # ex:
  #   class User
  #     belongs_to :parent, class_name: 'User'
  #   end
  #
  #   User.human_attribute_name(:name) => en.activerecord.attributes.user.name
  #   User.human_attribute_name(:parent) => en.activerecord.models.user
  def self.human_attribute_name(attribute, options = {})
    model = reflection_classes[attribute.to_sym]
    return model.model_name.human(options) if model

    super(attribute, options)
  end
end