The Rails deployment flow is really smooth thanks to the powerful (and easy to use) Capistrano.

Capistrano not only works with Rails and other Ruby code bases, but also code bases in any programming languages, such as PHP!

Here is an overview of what I did to get one of our PHP production sites up and running with Capistrano.

If you don’t already have Ruby and Rubygems installed, install them!

After you got ruby and rubygems, install Capistrano and its related gems -

gem install capistrano-ext railsless-deploy

Now, navigate to your application’s directory and run capify ., this will generate some necessary files for Capistrano to recognise your app.

Open up the generated Capfile file and replace the content of the file with:

require 'rubygems'
require 'railsless-deploy'
load 'config/deploy'

Okay, now we need to set up the actual deployment recipe in the config/deploy.rb file. But before doing so, we need to set up our deployment server with proper user and deployment permission.

We chose to set up a new user called deploy specifically for deployment purpose, for example -

useradd deploy

Then of course, we need the SSH keys for this deployment user, so switch to this user (su deploy) and -

ssh-keygen

We use GitHub, so simply copy the content of the public key (~/.ssh/id_rsa.pub) and add it to the deploy keys section of the Github repository.

Don’t forget to also add GitHub to the .ssh/known_hosts file, you can do this by manually cloning your repository on the deployment server.

Great! Now let’s do the last step - create the actual deployment recipe!

Open up config/deploy.rb file and you will see some default deployment tasks. Everyone has different needs, so I’m going to paste our deploy.rb file (masked with added comments) for your reference.

set :user, "deploy"
set :application, "YOUR_APPLICATION_NAME"
set :domain, "YOUR_APPLICATION_DOMAIN_NAME"
set :repository, "THE_ADDRESS_OF_THE_APPLICATION_REPOSITORY"
set :deploy_to, "/var/www/#{domain}"
set :shared_path, "#{deploy_to}/shared"
set :use_sudo, false

set :scm, :git
set :branch, 'master'
set :deploy_via, :remote_cache

role :web, "ADDRESS_OF_YOUR_WEB_SERVER"
role :app, "ADDRESS_OF_YOUR_APP_SERVER" # this can be the same as the web server
role :db, "ADDRESS_OF_YOUR_DB_SERVER", :primary => true # this can be the same as the web server

namespace :deploy do
  task :start do ; end
  task :stop do ; end
  task :restart, :roles => :app, :except => { :no_release => true } do
  run "#{try_sudo} /etc/init.d/lsws reload" # we use LiteSpeed Web Server
  end
end

# The task below serves the purpose of creating symlinks for asset files.
# Large asset files like user uploaded contents and images should not be checked into the repository anyway, so you should move them to a shared location.

task :create_symlinks, :roles => :web do
  run "ln -s #{shared_path}/uploads #{current_release}/uploads"
  run "ln -s #{shared_path}/zb #{current_release}/zb"
end

# Let's run the task immediately after the deployment is finalised.

after "deploy:finalize_update", :create_symlinks

That’s it! Now you should be able to deploy your application by -

cap deploy:setup
cap deploy