Capistrano crotab tasks for multiple projects deployed from same user

README.md

Capistrano + crontab + multiple projects sharing a linux user

1. put crontab.cap into lib/capistrano/tasks/crontab.cap
2. create your crontab file (you can use ERB) and put it somewhere
3. set crontab_template to point to your crontab file, eg:

set :crontab_template, File.expand_path('./crontab.erb', File.dirname(__FILE__))

4. setup crontab:update when appropriate, eg:

after :publishing, 'crontab:update'

5. Add role cron to all servers that you want the crontab to be updated.

6. Enjoy!

crontab.cap

namespace :crontab do
  task :update do
    invoke 'crontab:render'
    invoke 'crontab:reload'
  end

  task :render do
    on roles(:cron) do
      template_path = fetch :crontab_template
      template = ERB.new(File.new(template_path).read).result(binding)

      execute :mkdir, "-p #{crontabs_dir}"
      upload! StringIO.new(template), crontab_path
    end
  end

  task :reload do
    on roles(:cron) do
      execute "cat #{crontabs_dir}/* | crontab -"
    end
  end

  def crontab_path
    "#{crontabs_dir}/#{fetch :application}"
  end

  def crontabs_dir
    @home_dir ||= capture("echo $HOME").lines.first.chomp
    "#{@home_dir}/crontabs"
  end
end

crontab.erb

# * * * * * command to be executed
# - - - - -
# | | | | |
# | | | | +- - - - day of week (0 - 6) (Sunday=0)
# | | | +- - - - - month (1 - 12)
# | | +- - - - - - day of month (1 - 31)
# | +- - - - - - - hour (0 - 23)
# +- - - - - - - - minute (0 - 59)

# import todays data
5 0 * * * cd <%= fetch :deploy_to %>/current && bin/bundle rake import:today