If you are planning to deploy your Rails application using Capistrano 3, RVM, Unicorn, and Nginx then this is for you. You can follow these steps to help you automate your deployment to your cloud server. If you want to secure your server, you can read through this.
Install RVM
Log in to your system and install RVM. RVM has a good installation guide which you can find in detail here.
Or, you can just run this on your server.
$ curl -sSL https://get.rvm.io | bash -s stable --ruby
To verify
$ rvm version
rvm 1.25.14 (stable) by Wayne E. Seguin <wayneeseguin@gmail.com>, Michal Papis <mpapis@gmail.com> [https://rvm.io/]
Install Git
For Ubuntu:
$ sudo apt-get install git
If you are running on CentOS
$ sudo yum install git
To check whether it installed correctly
$ git --version
git version 1.8.3.2
Setup Nginx
Nginx is a reverse proxy server. It basically serves all the client requests coming in to your server, and directs it to the appropriate backend server. In this case, your backend server would be Unicorn which hosts your Rails application.
Installing Nginx is simple with the package management tool.
For Ubuntu
sudo apt-get install nginx
For CentOS
sudo yum install nginx
Once you have this installed, you will need to add default.conf.
$ sudo vim /etc/nginx/conf.d/default.conf
Add the following content. Make sure to edit it to match your configurations
upstream unicorn {
server unix:/tmp/unicorn.[APP_NAME].sock fail_timeout=0;
}
server {
listen 80 default deferred;
# server_name example.com;
root [APP_DIRECTORY]/[APP_NAME]/current/public; # e.g. /var/apps/rails_blog/current/public
location ^~ /assets/ {
gzip_static on;
expires max;
add_header Cache-Control public;
}
location ~ ^/(robots.txt|sitemap.xml.gz)/ {
root [APP_DIRECTORY]/[APP_NAME]/current/public; # e.g. /var/apps/rails_blog/current/public
}
try_files $uri/index.html $uri @unicorn;
location @unicorn {
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_pass http://unicorn;
}
error_page 500 502 503 504 /500.html;
client_max_body_size 4G;
keepalive_timeout 10;
}
After adding this config, try to start nginx
sudo service nginx start
You can check whether nginx is running correctly
$ ps aux|grep nginx
You should see nginx listed in the result.
Setup your App
Configure Unicorn in your Rails application
Add the unicorn gem into your Gemfile
$ vim Gemfile
gem 'unicorn'
Then add the unicorn configuration:
$ vim config/unicorn/production.rb
root = "[APP_DIRECTORY]/[APP_NAME]/current" # e.g. /var/apps/rails_blog/current
working_directory root
pid "#{root}/tmp/pids/unicorn.pid"
stderr_path "#{root}/log/unicorn.log"
stdout_path "#{root}/log/unicorn.log"
worker_processes 8 # update this with your preference
timeout 30
preload_app true
listen '/tmp/unicorn.[APP_NAME].sock', backlog: 64
before_fork do |server, worker|
Signal.trap 'TERM' do
puts 'Unicorn master intercepting TERM and sending myself QUIT instead'
Process.kill 'QUIT', Process.pid
end
defined?(ActiveRecord::Base) and
ActiveRecord::Base.connection.disconnect!
end
after_fork do |server, worker|
Signal.trap 'TERM' do
puts 'Unicorn worker intercepting TERM and doing nothing. Wait for master to send QUIT'
end
defined?(ActiveRecord::Base) and
ActiveRecord::Base.establish_connection
end
# Force the bundler gemfile environment variable to
# reference the capistrano "current" symlink
before_exec do |_|
ENV['BUNDLE_GEMFILE'] = File.join(root, 'Gemfile')
end
Add Capistrano 3 to your app
Add the gem
$ vim Gemfile
group :development do
gem 'capistrano-rails'
gem 'capistrano-rvm'
gem 'capistrano3-unicorn'
end
Generate the necessary Capistrano files
$ bundle exec cap install
Update the generated Capfile
$ vim Capfile
require 'capistrano/setup'
require 'capistrano/deploy'
require 'capistrano/rvm'
require 'capistrano/bundler'
require 'capistrano/rails/assets'
require 'capistrano/rails/migrations'
require 'capistrano3/unicorn'
# Load custom tasks from `lib/capistrano/tasks' if you have any defined
Dir.glob('lib/capistrano/tasks/*.rake').each { |r| import r }
Update deploy.rb
$ vim config/deploy.rb
lock '3.3.5'
set :application, [APP_NAME]
set :repo_url, 'git@github.com:[GITHUB_ACCOUNT_NAME]/[APP_NAME].git' # change this to your git server
ask :branch, proc { `git rev-parse --abbrev-ref HEAD`.chomp }.call
set :use_sudo, false
set :bundle_binstubs, nil
set :linked_files, fetch(:linked_files, []).push('config/database.yml')
set :linked_dirs, fetch(:linked_dirs, []).push('log', 'tmp/pids', 'tmp/cache', 'tmp/sockets', 'vendor/bundle', 'public/system')
after 'deploy:publishing', 'deploy:restart'
namespace :deploy do
task :restart do
invoke 'unicorn:stop'
invoke 'unicorn:reload'
end
task :stop do
invoke 'unicorn:stop'
end
end
Update capistrano production.rb
$ vim config/deploy/production.rb
set :port, 22
set :user, [username] # e.g. 'deploy'
set :deploy_via, :remote_cache
set :use_sudo, false
set :branch, [BRANCH_TO_DEPLOY] # e.g. 'master'
server [HOST_IP], # e.g. 192.xxx.xxx.xxx
roles: [:web, :app, :db],
port: fetch(:port),
user: fetch(:user),
primary: true
set :deploy_to, "[APP_DIRECTORY]/#{fetch(:application)}" # e.g. "/var/apps/rails_blog"
set :ssh_options, {
forward_agent: true,
auth_methods: %w(publickey),
user: 'deployer',
}
set :rails_env, :production
set :conditionally_migrate, true
Setup Git Server
To make sure that the deployment script runs smoothly, you need to add your server’s pub key to your git server.
Generate your pub key if you have not done so:
ssh-keygen -t rsa -C "[EMAIL_ADDRESS]"
This will generate a public key: ~/.ssh/id_rsa.pub
Copy the content of this file onto your git server profile.
Verify deploy
Once everything has been setup, try to verify everything by running this
cap production deploy:check
If everything runs smoothly, then you are more or less set.
Deploy application
To deploy this in production
cap production deploy
That should deploy your app in production. Once you access the IP address of your server on a browser, you should be greeted by your app’s home page.
Many thanks to Chuck J Hardy for his guide which helped me tremendously.