add-site.rb

#!/usr/bin/env ruby

def run_silently(command)
  IO.popen(command) { |f| f.read }
end

if ARGV.size < 2
  puts "Usage: #{File.basename(__FILE__)} domain [path=/var/apps/#\{domain\}] [user=deployer] [--no-capistrano]"
end

TEMPLATE = <<-END
<VirtualHost *:80>
  ServerName DOMAIN
  DocumentRoot PATH
  <Directory "PATH">
     Options FollowSymLinks
     AllowOverride None
     Order allow,deny
     Allow from all
  </Directory>
</VirtualHost>
END

capistrano = !ARGV.include?("--no-capistrano")
domain     = ARGV[0]
path       = File.expand_path(ARGV[1] || "/var/apps/#{domain}")
user       = ARGV[2] || "deployer"

print "1. Creating directory w/ correct permissions"
run_silently "mkdir -p '#{path}'"
run_silently "chown -R #{user}:deploy '#{path}'"
puts " [DONE]"

print "2. Creating vhost file" 
vhost_file = "/etc/apache2/sites-available/#{domain}"
full_path  = File.join(path, (capistrano ? "current/public" : "public"))
File.open(vhost_file, "w+") do |f|
  f.puts(TEMPLATE.gsub("DOMAIN", domain).gsub("PATH", full_path))
end
run_silently "chown root '#{vhost_file}'"
puts " [DONE]"

print "3. Enabling the site"
run_silently "a2ensite #{domain}"
puts " [DONE]"

print "4. Restarting Apache 2"
run_silently "/etc/init.d/apache2 restart"
puts " [DONE]"