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Hello World Ruby on Rails App Tutorial using Mac

Ruan Bekker -

In this tutorial, we will setup a basic ruby on rails web app, that consists of a /hello_world and a /status controller. The hello_world controller will return Hello, World and our /status controller will return a HTTP 204 no content response code.

Setup Ruby on Rails

Setup Ruby on Rails on your Mac:

$ brew install rbenv ruby-build

$ echo 'if which rbenv > /dev/null; then eval "$(rbenv init -)"; fi' >> ~/.bash_profile
$ source ~/.bash_profile

$ rbenv install 2.5.0
$ rbenv global 2.5.0
$ ruby -v

$ gem install rails -v 5.1.4
$ benv rehash

Creating the App

Create your ruby on rails application:

$ rails new fist-app
$ cd first-app
$ rails server

Route Config

Our routes config:

$ cat config/routes.rb
Rails.application.routes.draw do
  # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
  get 'hello_world', to: 'hello_world#call'
  get 'status', to: 'status#call'
end

Controllers

Configure the hello_world controller:

$ cat app/controllers/hello_world_controller.rb

class HelloWorldController < ApplicationController
  def call
    render body: "Hello, World"
  end
end

Configure the status controller:

$ cat app/controllers/status_controller.rb

class StatusController < ApplicationController
  def call
    [204, {}, ['']]
  end
end

Testing

For our hello world controller:

$ curl -i http://localhost:3000/hello_world
HTTP/1.1 200 OK
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
Content-Type: text/plain; charset=utf-8
ETag: W/"565339bc4d33d72817b583024112eb7f"
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: 62441a6d-faa3-42d5-a5a2-bcf7eff5e917
X-Runtime: 0.001940
Transfer-Encoding: chunked
Hello, World

For our status controller:

$ curl -i http://localhost:3000/status
HTTP/1.1 204 No Content
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
Cache-Control: no-cache
X-Request-Id: bec91213-ff82-4fc6-8698-3ee7622b1f51
X-Runtime: 0.075504

Resources: