Install Ruby on Rails in CentOS7

1) Install prerequisites.

[shabbir@compute1~]$ sudo yum install -y git-core zlib zlib-devel gcc-c++ patch readline readline-devel libyaml-devel libffi-devel openssl-devel make bzip2 autoconf automake libtool bison curl sqlite-devel

2) Install rbenv

[shabbir@compute1~]$ git clone git://github.com/sstephenson/rbenv.git .rbenv

[shabbir@compute1~]$ echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bash_profile

[shabbir@compute1~]$ echo 'eval "$(rbenv init -)"' >> ~/.bash_profile
  

[shabbir@compute1~]$ exec $SHELL
  

[shabbir@compute1~]$ git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
  

[shabbir@compute1~]$ echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bash_profile
  

[shabbir@compute1~]$ exec $SHELL

Reboot the machine.

[shabbir@compute1~]$ systemctl reboot

3) Install Ruby

[shabbir@compute1 ~]$ rbenv install -v 2.2.3

[shabbir@compute1 ~]$ rbenv global 2.2.3

Verify that Ruby was installed properly.
[shabbir@compute1 ~]$ ruby -v
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]

[shabbir@compute1 ~]$ echo "gem: --no-document" > ~/.gemrc

[shabbir@compute1 ~]$ gem install bundler

4) Install Rails 

[shabbir@compute1 ~]$ gem install rails -v 4.2.4

[shabbir@compute1 ~]$ rbenv rehash 

Verify that Rails was installed properly.
[shabbir@compute1 ~]$ rails -v

Rails 4.2.4

5) Install JavaScript Runtime

Install EPEL Repository.
[shabbir@compute1 ~]$ sudo yum -y install epel-release

[shabbir@compute1 ~]$ sudo yum install nodejs

6) Install Database

[shabbir@compute1 ~]$ sudo yum groupinstall mariadb

[shabbir@compute1 ~]$ sudo yum install mariadb-devel

[shabbir@compute1 ~]$ sudo systemctl enable mariadb

[shabbir@compute1 ~]$ sudo systemctl start mariadb 

[shabbir@compute1 ~]$ gem install mysql




[shabbir@compute1 ~]$ rbenv rehash



7) Create 'Hello World' Application

7.1) Create Demo Project

[shabbir@compute1 ~]$ rails new demo

7.2) Start the Web Server.

[shabbir@compute1 ~]$ cd demo 

[shabbir@compute1 demo]$ rails server

7.3) Open a browser and type the following URL. http://localhost:3000
 

NOTE: To stop the web server, hit Ctrl+C in the terminal window where it's running.

7.4) Create a new controller called "welcome" with an action called "index".

[shabbir@compute1 demo]$ generate controller welcome index
      create  app/controllers/welcome_controller.rb
       route  get 'welcome/index'
      invoke  erb
      create    app/views/welcome
      create    app/views/welcome/index.html.erb
      invoke  test_unit
      create    test/controllers/welcome_controller_test.rb
      invoke  helper
      create    app/helpers/welcome_helper.rb
      invoke    test_unit
      invoke  assets
      invoke    coffee
      create      app/assets/javascripts/welcome.coffee
      invoke    scss
      create      app/assets/stylesheets/welcome.scss

The controller, is located at app/controllers/welcome_controller.rb and the view, located at app/views/welcome/index.html.erb.

7.5) Edit the View.

[shabbir@compute1 demo]$ vi app/views/welcome/index.html.erb

<h1>Hello, World!</h1>



7.6) Now that we have made the controller and view, we need to tell Rails when we want "Hello, World!" to show up. In our case, we want it to show up when we navigate to the root URL of our site, http://localhost:3000. At the moment, "Welcome aboard" is occupying that spot.

Edit the application's routing file.
[shabbir@compute1 demo]$ vi config/routes.rb

Uncomment the following line
  root 'welcome#index'


7.7) Ensure that the Web server is running. Open a browser and type the following URL. http://localhost:3000