Delayed job to use specific connection via ruby

Hello Guys,
           Yesterday  i was phasing one interesting problem. Sharing single database between 2 rails application but now i've requirement to use application specific table for delayed jobs.

Lets assume i've application called DemoApp & TestApp. And both sharing single DB called 'demo_app_prod'. Now for TestApp i required separate DB called 'test_app_prod' which has single table called 'delayed_jobs'.

Step1:

at TestApp you have database.yaml like
 login: &login
  adapter: mysql
  username: admin
  host: localhost  
  password:
 
development:
  <<: *login
  database: demo_app_dev

test:
  <<: *login
  database: demo_app_test
 
production:
  <<: *login
  database: demo_app_prod  

staging:
  <<: *login
  database: test_app_prod

Step2:
at TestApp added migration called 
   rails generate migration add_delayed_job

  class AddDelayedJob < ActiveRecord::Migration
  def connection
    ActiveRecord::Base.establish_connection(Rails.env).connection
  end
 
  def up
    oldEnv = Rails.env
    Rails.env = 'staging' #set environment variable from your database.yml
    ActiveRecord::Base.establish_connection(Rails.env)   
    create_table :delayed_jobs, :force => true do |table|
      table.integer  :priority, :default => 0 
      table.integer  :attempts, :default => 0  
      table.text     :handler                      
      table.text     :last_error                  
      table.datetime :run_at                       
      table.datetime :locked_at                    
      table.datetime :failed_at                    
      table.string   :locked_by          
      table.timestamps
    end
    Rails.env = oldEnv
    ActiveRecord::Base.establish_connection ActiveRecord::Base.configurations[Rails.env]
  end
 
  def down   
    oldEnv = Rails.env
    Rails.env = 'staging'
    ActiveRecord::Base.establish_connection(Rails.env).connection
    drop_table :delayed_jobs
    Rails.env = oldEnv
    ActiveRecord::Base.establish_connection ActiveRecord::Base.configurations[Rails.env]
  end
end

Step3:

 In initializers/delayed_job.rb add below lines

Delayed::Job.class_eval do
  establish_connection ActiveRecord::Base.configurations["local"]
end

This the easy way to establish multiple db connection via ruby for delayed job.