deploy.rb

load 'deploy/assets'

set :bundle_roles, [:app]    #{:except => {:no_release => true}} # e.g. [:app, :batch]
require 'bundler/capistrano'

set :application, "my_app"
set :repository,  "[email protected]:myname/#{application}.git"
set :user, 'deploy'
set :use_sudo, false

set :scm, :git
set :branch, "master"
set :deploy_via, :remote_cache
set :git_shallow_clone, 1

set :deploy_to, "~/#{application}"
set :keep_releases, 3

set :stages, %w(production staging)
set :default_stage, "staging"
require 'capistrano/ext/multistage'

set :application_env, 'production'

set :bundle_gemfile,  "Gemfile"
set :bundle_dir,      File.join(fetch(:shared_path), 'bundle')
set :bundle_flags,    "--deployment --quiet"

set :normalize_asset_timestamps, false

require 'capistrano-unicorn'

before  'deploy:finalize_update', 'deploy:symlink_sockets', 'deploy:symlink_configs'
after   'deploy', 'deploy:cleanup'
before  'deploy', 'set_start_time'
after   'deploy', 'log_duration'
after   'deploy:setup', 'deploy:setup_unicorn_dirs'

namespace :deploy do
  task :symlink_sockets, :roles => :web, :except => { :no_release => true } do
    run <<-CMD
      mkdir -p #{latest_release}/tmp &&
      rm -rf #{latest_release}/tmp/sockets &&
      ln -s #{shared_path}/sockets #{latest_release}/tmp/sockets &&
      rm -rf #{latest_release}/tmp/pids &&
      ln -s #{shared_path}/pids #{latest_release}/tmp/pids
    CMD
  end

  task :symlink_configs do
    run <<-CMD
      if [ -f #{shared_path}/config/backend.yml ]; then
        rm -f #{latest_release}/config/backend.yml &&
        ln -s #{shared_path}/config/backend.yml #{latest_release}/config/backend.yml ;
      fi
    CMD
  end

  task :setup_unicorn_dirs, :except => { :no_release => true } do
    dirs = ["#{shared_path}/sockets", "#{shared_path}/pids", "#{shared_path}/config"]
    dirs += shared_children.map { |d| File.join(shared_path, d.split('/').last) }
    run "#{try_sudo} mkdir -p #{dirs.join(' ')}"
    run "#{try_sudo} chmod g+w #{dirs.join(' ')}" if fetch(:group_writable, true)
  end
end

task :set_start_time do
  set :started_at, Time.now.to_f
end

task :log_duration do
  duration = (Time.now.to_f - started_at)
  logger.info "Deploy completed in %1.4f seconds" % duration
end

production.rb

role :web, "app1.somewhere"
role :app, "app1.somewhere"
role :db,  "app1.somewhere", :primary => true