config/deploy.rb on simple deploy

deploy.rb

namespace :deploy do
  set :db_user, 'set_db_user'
  set :db_password, 'set_db_password'
  set(:environment) { rails_env }
  set :master, 'localhost'
  set :slaves, []
  set :database_name, "dbprefix_#{rails_env}"

  # memcached config => [hostname:port]
  set :memcache_servers, ['localhost:11211']

  # redis config => [hostname, db_num]
  set :redis_game, [['localhost', 0], ['localhost', 1]]
  set :redis_game_slaves, []

  namespace :simple do
    desc "Setup a GitHub-style deployment."
    task :setup, :except => { :no_release => true } do
      transaction do
        on_rollback { run "rm -fr #{deploy_to}" }

        run "mkdir -p #{releases_path} && chmod g+rw #{releases_path}"
        # Then clone the code and change to the given branch
        unless deployed_dir_exists?(".git")
          run "umask 002 && git clone #{repository} #{releases_path}/current"
        end

        run 'git config --global user.email "deploy_user_email"'
        run 'git config --global user.name "deploy_user_name"'
      end
    end

    namespace :symlinks do
      desc "Make all the symlinks"
      task :make, :roles => :app, :except => { :no_release => true } do
        symlinks = {
          'assets'  => 'public/assets',
          'system'  => 'public/system',
          'log'     => 'log',
          'pids'    => 'tmp/pids',
          'sockets' => 'tmp/sockets',
        }

        # needed for some of the symlinks
        run "rm -rf #{current_path} && ln -s #{releases_path}/current #{current_path}"
        run "mkdir -p #{releases_path}/current/tmp"

        commands = symlinks.map do |from, to|
          "rm -rf #{current_path}/#{to} && mkdir -p #{shared_path}/#{from} && ln -s #{shared_path}/#{from} #{current_path}/#{to}"
        end
        commands << "rm -rf #{shared_path}/log && ln -s /media/ephemeral0/rails #{shared_path}/log"

        run "cd #{current_path} && #{commands.join(" && ")}"
      end
      after "deploy:simple:setup", "deploy:simple:symlinks:make"
    end

    desc "Update the deployed code."
    task :update_code, :except => { :no_release => true } do
      on_rollback { git "reset --hard #{latest_tag}" if latest_tag }
      git "fetch && git reset --hard origin/#{branch}"
      run_current "bundle install" if trigger_update?("Gemfile.lock")
    end
    after "deploy:simple:setup", "deploy:simple:update_code"

    # Tag `HEAD` with the release tag and message
    desc "Update the REVISION."
    task :tag, :except => { :no_release => true } do
      set :release_tag, release_tag_from_repository
      set :release_message, "Deployed at #{Time.now}"

      on_rollback { git "tag -d #{release_tag}" }
      if changed_files.count > 0
        git "tag #{release_tag} -m '#{release_message}'"
      end
    end

    set(:setup_database_triggers, %w(templates/database.yml.erb templates/shards.yml.erb))

    namespace :conf do
      desc 'Setup database.yml on simple deploy'
      task :database do
        if setup_database_triggers.detect {|path| trigger_update?(path)}
          put conf_template('database.yml', binding), "#{current_path}/config/database.yml"
          unless slaves.empty?
            put conf_template('shards.yml', binding), "#{current_path}/config/shards.yml"
          end
        end
      end
      after "deploy:simple:update_code", "deploy:simple:conf:database"

      desc 'Setup memcached.yml'
      task :memcached do
        if trigger_update?('templates/memcached.yml.erb')
          put conf_template('memcached.yml', binding), "#{current_path}/config/memcached.yml"
        end
      end
      after "deploy:simple:update_code", "deploy:simple:conf:memcached"

      desc 'Setup redis.yml'
      task :redis do
        if trigger_update?('templates/redis.yml.erb')
          put conf_template('redis.yml', binding), "#{current_path}/config/redis.yml"
        end
      end
      after "deploy:simple:update_code", "deploy:simple:conf:redis"
    end

    desc "Create database"
    task :create_database, :roles => :db, :except => { no_release: true } do
      if setup_database_triggers.detect {|path| trigger_update?(path)}
        run "cd #{current_path} && bundle exec rake db:create"
      end
    end
    after "deploy:simple:conf:database", "deploy:simple:create_database"

    desc 'Run the migrate rake task if migrations changed.'
    task :migrate do
      if trigger_update?('db/migrate')
        run_bundle "rake db:migrate"
      end
    end
    after "deploy:simple:update_code", "deploy:simple:migrate"

    namespace :seed do
      [:update, :truncate].each do |act|
        desc "#{act} Game Master data if changed from previous version."
        task act, :roles => :db, :except => {no_release: true} do
          cond = act == :truncate ? "TRUNCATE=1" : ""
          if trigger_update?("db/seeds")
            tables = changed_files.grep(/\Adb\/seeds.*\.yml\Z/).map{|p| p.split('/').last.gsub('.yml', '') }
            run_bundle "rake db:seed_fu TABLES=#{tables.join(',')} #{cond}"
          end
        end
      end
      after "deploy:simple:update_code", "deploy:simple:seed:update"
    end

    namespace :assets do
      set(:asset_precompilation_triggers, %w(app/assets vendor/assets Gemfile.lock config))

      desc 'Run the asset precompilation rake task if assets changed.'
      task :precompile do
        if asset_precompilation_triggers.detect {|path| trigger_update?(path)}
          run_bundle "rake RAILS_GROUPS=assets assets:precompile"
        end
      end
      after "deploy:simple:update_code", "deploy:simple:assets:precompile"
    end

    desc "Restart the application following a deploy"
    task :restart do
      top.unicorn.restart
    end

    desc "Remove all deployed files"
    task :destroy do
      sudo "rm -rf #{releases_path}/current"
    end

    desc "Rollback to previous release."
    task :rollback, :except => { :no_release => true } do
      if latest_tag
        git "tag -d #{latest_tag}"
        git "reset --hard #{latest_tag(false)}"
        restart
      else
        abort "This app is not currently deployed"
      end
    end

    after "deploy:simple:setup", "god:start"
  end
end