Set cron jobs

1. Add gem  in Gemfile

Gemfile
gem 'whenever', :require => false

2. On the console, inside the project

wheneverize.

3. Define the method to be called in the cron job

app/model/user.rb

def self.employee_delete
    candidates = Employee.where('status NOT IN (?) and Date(created_at) < ?', ['verification', 'confirmed'], Date.today - 3.months)
    candidates.destroy_all

  end
4. add file schedule.rb to the config folder
config/schedule.rb

set :output, "log/cron_log.log"
set :environment, 'staging'

every 1.day, :at => '12.00 am' do
  runner 'Employee.employee_delete'

end

5. On the console
whenever --update-crontab