Rake task to restart delayed_job_monitor if app not in maintenance mode

delayed_job_monitor_restart.rake

# Workers are watched by built-in delayed_job_monitor
# Use [bundle exec] rake jobs:restart to restart delayed_job_monitor
# * if app in maintenance mode (cf. maintenance.html), will do nothing
# * else if delayed_job_monitor yet running, will do nothing
# * else will restart delayed_job_monitor
# Can be used via a cron, for example :
# 15 * * * * RAILS_ENV=testing bundle exec rake jobs:restart

namespace :jobs do
  desc "Restart delayed_job_monitor if no worker yet running"
  task :restart do
    maintenance_file = Rails.root + 'public/system/maintenance.html'
    unless maintenance_file.exist?
      cmd = "#{Rails.root}/script/delayed_job"
      args = ["start", "-m"]
      exec cmd, *args
    end
  end
end