We’ve adopted a standard convention for deploying Rails apps that places the files in a subdomain of our clients’ domains. Since we use Plesk, there are some steps we have to take to get Capistrano deploys working. Since we deploy a lot of apps, I decided to write this guide as much for the office as for anyone who may find it useful. Let’s go through the steps:

1. Create your subdomain in Plesk (ie. myrailsapp)
2. Navigate to the /domain.com/subdomains/myrailsapp/conf directory
3. Create a vhost.conf file. Again, we use a convention that creates a new directory within /myrailsapp that holds our rails code. Fittingly, we name the directory /rails. The DocumentRoot points to the public directory of our application. Enter the following into the vhost.conf file:

DocumentRoot /var/www/vhosts/domain.com/subdomains/myrailsapp/rails/current/public 
RailsEnv production

4. If you haven’t already installed the capistrano and capistrano-ext (for multistage environments such as testing and production deploys), you’ll need to get them. The Capistrano tutorials will walk you through that process.
5. With the gems installed, now we want to capify our code. In your root rails app directory, enter the following command. (You may have to sudo the command depending on your directory permissions.)

capify .

This will create two files: Capfile and deploy.rb in your /config directory.

6. Open up your deploy.rb file and enter your configuration variables. Again, you can refer to the Capistrano tutorials for help.
7. If you are only planning to deploy to a single environment, you’re work is done. If you plan a multi-stage environment, you’ll want to set the stages in your deploy.rb file and require the capistrano-ext gem like this:

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

8. Within the /config directory, create a new /deploy directory and two new files, testing.rb and production.rb. These files will provide the deploy details for each environment.
9. Open up your new .rb files and enter the following for each environment:

   
   #############################################################
   #   Application
   #############################################################
   
   set :application, "myrailsapp"
   set :deploy_to, "/var/www/vhosts/domain.com/subdomains/myrailsapp/rails"
   
   #############################################################
   #   Settings
   #############################################################
   
   default_run_options[:pty] = true
   ssh_options[:forward_agent] = true
   set :use_sudo, true
   set :scm_verbose, true
   set :rails_env, "testing" 
   
   #############################################################
   #   Servers
   #############################################################
   
   set :user, "username"
   set :password, "user_password"
   set :domain, "myrailsapp.domain.com"
   server domain, :app, :web
   role :db, domain, :primary => true
   
   #############################################################
   #   Passenger
   #############################################################
   
   namespace :deploy do
     desc "Create the database yaml file"
     task :after_update_code do
       db_config = <<-EOF
       production:    
         adapter: mysql
         encoding: utf8
         username: database_username
         password: database_password
         database: database
         host: localhost
       EOF
       
       put db_config, "#{release_path}/config/database.yml"
   
     end
       
     # Restart passenger on deploy
     desc "Restarting mod_rails with restart.txt"
     task :restart, :roles => :app, :except => { :no_release => true } do
       run "touch #{current_path}/tmp/restart.txt"
     end
     
     [:start, :stop].each do |t|
       desc "#{t} task is a no-op with mod_rails"
       task t, :roles => :app do ; end
     end
     
   end
   
   

   Then add the details of your repository for either subversion or git.

   
   
   #############################################################
   #   GIT
   #############################################################
   
   set :scm, :git
   set :branch, "master"
   set :repository, "git@github.com:your_github_path/MYRAILSAPP.git"
   set :deploy_via, :remote_cache
   ssh_options[:forward_agent] = true
   
   #############################################################
   #   SVN
   #############################################################
   
   set :scm, :svn
   set :branch, "trunk"
   set :scm_user, 'username'
   set :scm_password, "user_password"
   set :repository, Proc.new { "--username #{scm_user} --password '#{scm_password}' --no-auth-cache http://doman.com/path/to/your/subversion/repository/#{application}/trunk" } 
   
   set :deploy_via, :remote_cache
   ssh_options[:forward_agent] = true
   
   

10. That’s it; you’re ready to deploy. Back at your terminal window, you’ll type the respective environment to which you’re deploy:

cap testing deploy

A final note: make sure the user specified in your deploy files has permission to create directories on the server, otherwise your /releases directories will not be created.

Feel free to ask any questions if you’re having trouble with your Plesk subdomain and Capistrano deployment. Good luck!

I hit a wall recently as I tried to track down the reason validates_presence_of was not displaying errors. Rails validations normally go off without a hitch, so I was a bit stumped when my attempts to save blank fields were not triggering the appropriate messages. After ensuring my model and view were correct, I fired up the console to make sure my validations were working in the first place. After loading an object and attempting a save, I checked to see if the errors object returned false. Sure enough, all of the validations were enforced.

>> @contact = Contact.find_by_id(9)
=> #
>> @contact.save
=> false
>> @contact.errors.empty?
=> false
>> @contact.errors.count
=> 6
>> @contact.errors.each_full { |msg| puts msg }
   City No blanks
   Zip No blanks
   First name No blanks
   Address No blanks
   Last name No blanks
   State No blanks

After more head banging, I was ready to give up with a simple notification workaround on the update method.

if !@contact.errors.empty?
  flash[:error] = "You are missing required fields."
  redirect_to edit_contact_url(@contact.user)
else
  flash[:notice] = "Successfully saved."
  redirect_to contact_url(@contact.user)
end

That works, but it doesn’t take advantage of the Rails’ error_messages_for helper to display helpful messages and highlight problem fields. Then I realized the initial error. During redirects, the object’s data isn’t passed, so while the validations were enforced (the form data would not save upon submission), no errors were being output to the screen. My new code rendered the page along with the error messages:

if !@contact.errors.empty?
  render :action => 'edit'
else
  flash[:notice] = "Successfully saved."
  redirect_to contact_url(@contact.user)
end