Capistrano recipe to deploy a simple Rails app with frozen gems from a given repository tag

deploy.rb

set :application, "foobar"
set :deploy_to, "/home/deployer/foobar"
set :user, "deployer"
set :use_sudo, false
set :deploy_via, :export

set :repository do
  fail "Provide TAG environment variable to select tag to deploy from." if ENV['TAG'].nil?
  "https://svn.example.com/#{application}/tags/" + ENV['TAG']
end

server "app.example.com", :app, :web, :db, :primary => true

namespace :deploy do
  task :default, :roles => :app do
    # Always deploy with migrations by default
    migrations
  end

  task :after_update_code, :roles => :app do
    # Copy configuration
    run "ln -s #{shared_path}/config/database.yml #{release_path}/config/database.yml"

    # Build native gems
    run "cd #{release_path} && rake gems:build"
  end

  task :restart, :roles => :app do
    # Passenger restart
    run "touch #{current_path}/tmp/restart.txt"
  end

  task :start, :roles => :app do
    restart
  end

  task :stop, :roles => :app do
    # Nothing to do for Passenger
  end
end