Simple User Tracking For Rails

user_tracking.rb

# (concern) e.g. for Post model
module UserTrackable

  extend ActiveSupport::Concern

  included do
    before_create :set_created_by
    before_save   :set_updated_by

    belongs_to :created_by, class_name: 'User', foreign_key: 'created_by_id'
    belongs_to :updated_by, class_name: 'User', foreign_key: 'updated_by_id'

    scope :created_by, ->(user) { where(created_by_id: user.id) }
    scope :updated_by, ->(user) { where(updated_by_id: user.id) }
  end

  protected

  def set_created_by
    self.created_by = User.current_user
    true
  end

  def set_updated_by
    self.updated_by = User.current_user
    true
  end

end

# (concern) e.g. for User model
module UserTracker

  extend ActiveSupport::Concern

  included do
    def self.current_user=(user)
      RequestStore.store[:ut_current_user] = user
    end

    def self.current_user
      RequestStore.store[:ut_current_user]
    end    
  end

end

# Save the current user for model access
class ApplicationController < ActionController::Base
  before_action :set_current_user
  
  private
  
  def set_current_user
    User.current_user = current_user
  end
end

# Example Migration

class AddUserTrackingToPost < ActiveRecord::Migration
  def change
    add_column :posts, :created_by_id, :integer
    add_column :posts, :updated_by_id, :integer

    add_index :posts, :created_by_id
    add_index :posts, :updated_by_id
  end
end

# Gemfile
gem 'request_store'

# example models
class User < ActiveRecord::Base
  include UserTracker
end

class Post < ActiveRecord::Base
  include UserTrackable
end

Post.first.created_by # => User
Post.first.updated_by # => User

It's great. Thank you. I was thinking to have a separate table to store that information. like audit_log table and have columns

action_name => create/update
record_name => User
record_id => 123
whodunit => 456

this way we do not need to add columns to each new table.

check the audited gem