Capistrano Recipe

deploy.rb

require 'bundler/capistrano'
load 'deploy/assets'

set :domain, "example.com"
set :application, "application"
set :user, "deploy"
set :password, "secret"
set :use_sudo, false
set :deploy_to, "/home/#{user}/www/#{application}"
set :shared_path, "#{deploy_to}/shared"

set :repository, "git repo address"
set :scm, "git"
set :branch, "master"
set :keep_releases, 3
set :deploy_via, :remote_cache
set :scm_username, ""
set :scm_password, ""

default_run_options[:pty] = true
ssh_options[:forward_agent] = true

role :web, domain
role :app, domain
role :db,  domain, :primary => true

after  "deploy:finalize_update", "deploy:symlink_configs"
after  'deploy:symlink_configs', 'deploy:migrate'

namespace :deploy do

  desc "Restart Application"
  task :restart, :roles => :app do
    run "touch #{deploy_to}/#{shared_dir}/tmp/restart.txt"
  end

  desc "Setup Standard Configuration Links"
  task :symlink_configs, :roles => :app do
    run "ln -nfs #{shared_path}/database.yml #{release_path}/config/database.yml"
    run "rm -rf  #{release_path}/tmp"
    run "ln -nfs #{shared_path}/tmp #{release_path}/tmp"
  end

  desc "init database by Seed"
  task :seed, :roles => :app do
    run "cd #{latest_release} && bundle exec rake db:seed RAILS_ENV=production"
  end

end

Don't forget add "require 'rake/dsl_definition'" in Rakefile