Part 2. Setup Capistrano on the Rails app and run a test deploy to your server

Starting Point

• You have got your Rails app under version control with SVN as described in the first tutorial
• First make sure you have Capistrano installed, you can get it as a free Ruby gem with;

  gem install capistrano

• ‘Apply’ capistrano to your Rails app on the dev box, this creates some config files locally for Capistrano deployment to work.

  cap --apply-to /u/apps/sitename.com sitename.com

• Edit the Capistrano’s deploy configuration in /u/apps/sitename.com/config/deploy.rb to set the correct roles for your server;

  set :repository, "svn+ssh://matt@dagobah/svn/#{application}"
  role :web, "server"
  role :app, "server"
  role :db,  "server"
  set :deploy_to, "/u/apps/#{application}"
  

• From within the Rails directory (/u/apps/sitename.com) run the rake ‘setup’ task to remotely setup Capistrano’s directories on your server;

  rake remote:exec ACTION=setup

• Try a test deploy to the server (may ask for password during sudo) this will;
  • Checkout the latest revision of your application from your remote repository to the /u/apps/sitename.com/releases directory on your server
  • Update (or create) the /u/apps/sitename.com/current symlink so it points to this new revision

    rake deploy

• If all goes well, your Rails app should be checked out under /u/apps/sitename.com/current on your remote server. Run ‘rake deploy’ again if you like and see what happens. A new ‘release’ will be checked out to /u/apps/sitename.com/releases/timestamp/ and the symlink at /u/apps/sitename.com/current will be automatically setup to point to it.

Capistrano Tips

• Obviously with lots of deploys, you’ll start getting loads of release directories on your server, all containing your entire Rails app. You can run the ‘cleanup’ command to remove older releases. In config/deploy.rb – set the following to say how many releases you’d like to keep after a cleanup

  set :keep_releases, 3

• Then in the Rails directory run;

  cap cleanup

So there you have it, you can now deploy using Capistrano to your server from your dev box and your Rails app is safely under SVN version control. There is loads more you can do with Capistrano (see the links below)

In the next part of this guide, I’ll go through building the hosting stack (lighttpd/pound/mongrel) on your server. And making use of Capistrano to help with deploying your versioned Rails app around an unversioned folder containing the mints/ stats package (which we’ll also get running under PHP with lighttpd)

References

• Capistrano
• Avoiding SUDO on Capistrano
• PART 1. Setting up SVN
• PART 3. Lighttpd, Pound and Mongrel with Rails