All about REST API on Ruby on Rails

REST API

$ rake routs

----- config/routes.rb
resources :subjects

resources :subjects, except: :destroy

resources :sobjects, only: :index

resources :subjects, only: [:index, :show]

resources :subjects, except: [:destroy, :edit, :update]

---- Bad way
resources :subjects, only: :index
resources :teachers, only: :index
resources :students, only: :index
---- Good way
with_options only: :index do |list_only|
  list_only.resources :subjects
  list_only.resources :teachers
  list_only.resources :students


resorces :episodes

constraints subdomain: 'api' do 
  resources :subjects
  resources :teachers
end

C:\Windows\System32\drivers\etc\hosts  => for set a hosting

-------------------------------------------------------- 1
namespace :api, path: '/', constraints: {subdomain: 'api'} do
  resources :subjects
  resources :students
end
resources :pages

app/controllers/api/subjects_controller.rb
module Api
  class SubjectsController < ApplicationController
  end
end

config/initializers/inflectos.rb
ActiveSupport::Inflector.inflections(:en) do |inflect|
  inflect.acronym 'API'
end

app/controllers/pages_controller.rb
class PageController < ApplicationController
end
------------------------------------------------------- end 1



Chapter 2
------------------------------------------------------- 2
namespace :api, path: '/', constraints: {subdomain: 'api'} do
  resources :subjects
end

test/integration/listing_subject_test.rb

require 'test_helper'

class ListingSubjectsTest < ActionDispatch::IntegrationTest
  setup { host! 'api.example.com'}
  test 'returns list of all subjects' do
    get '/zombies'
    assert_equal 200, response.status
    refute_empty response.body
  end
end
------------------------------------------------------- end 2


------------------------------------------------------- 3

module API
  class SubjectsController < ApplicationController
    def index
      subjects = Subjects.all
      render json: subjects, status: 200
    end
  end
end

/subjects
/subjects/:id
/subjects?id=1

/subjects?weapon=axe         Filters
/subjects?keyword=Amir       Searches
/subjects?page2&per_page=25  pagination


module API
  class SubjectsController < AplicationController
    def index
      subjects = Subject.all
      if weapon = params[:weapon]
        subjects = subjects.where(weapon: weapon)
      end
      render json: subjects, status: 200
    end
    
    def show
      subject = Subject.find(params[:id])
      render json: subject, status: 200
      #render json: subject, status: ok
    end
    
  end
end

------------------------------------------------------- end 3

$curl : using for GET testing
$curl http://api.cs-subject-dev.com:3000/subject


------------------------------------------------------- 4

class SubjectsController < ApplicationController
  def index
    subjects = Subjects.all
    respond_to do |format|
      format.json { render json: subjects, status: 200 }
      format.xml { render xml: subjects, status: 200 }
    end
  end
end

------------------------------------------------------- end 4


------------------------------------------------------- 5
-if we whant to have a respond
class EpisodesController < ApplicationController
  def create
    episode = Episode.new(episode_params)
    if episode.save
      render json: episode, status:201, location: episode 
    end
  end
  
  private
    def episode_params
    params.require(:episode).permit(:title, :description)
  end
end


class EpisodesController < ApplicationController
  def create
    episode = Episode.new(episode.params)
    if episode.save
      render nothing: true, status: 204, location: episode
    emd
  end
  ...
end

class EpisodesController < ApplicationController
  def create
    episode = Episode.new(episode.params)
    if episode.save
      head 204, location: episode
    emd
  end
  ...
end

------------------------------------------------------- end 5

------------------------------------------------------- 6

class Episode < ActiveRecord::Base
  validates :title, presence: true
end

class EpisodesController < ApplicationController
  def create
    episode = Episode.new(episode_params)
    if episode.save
      render json: episode, status: :created, location: episode
    else
      render json: episode.errors, status: 422
    end
  end
  
  ...
  
end

------------------------------------------------------- end 6

------------------------------------------------------- 7

module V1
  class SubjectsControllers < ApplicationControllers
    def
      render json: "#{@remote_ip} Version One", status: 200
    end
  end
end

module V2
  class SubjectsControllers < ApplicationControllers
    def
      render json: "#{@remote_ip} Version Two", status: 200
    end
  end
end

class ApplicationController < ApplicationController::Base
  before_action ->{@remote_ip = request.headers['REMOTE_ADDR']}
end

module V2
  class VersionController < ApplicationController
    abstract!
  
    before_action :audit_logging_for_v2
    def audit_logging_for_v2
  end
end

------------------------------------------------------- end 7

AUTH
------------------------------------------------------- 8
class EpisodesController < ApplicationController
  before_action :authenticate
  
  def index
    episodes = Episode.all
    render jsone: episodes, status: 200
  end
  
  protected
    def authenticate
      authenticate_or_request_with_http_basic do |username, password|
        User.authenticate(username, password)
      end
    end
end
------------------------------------------------------- end 8