Rspec API Helper

rspec_api_helper.rb

#rspec/support/rspec_api_helper.rb
module RspecApiHelper
  module ExampleMethods
    def objectize_resources(json, root: root)
      array = []
      array_hash = HashWithIndifferentAccess.new(MultiJson.load(json))

      if root
        array_hash = array_hash[root]
      end

      array_hash.each do |resource|
        array << object_hash(resource)
      end

      return array
    end

    def objectize_resource(json, root: root)
      hash = HashWithIndifferentAccess.new(MultiJson.load(json))
      if root
        obj = object_hash(hash[root])
      else
        obj = object_hash(hash)
      end

      return obj
    end

    def object_hash(hash)
      ObjectHash.new(hash)
    end

    class ObjectHash
      attr_accessor :hash
      def initialize(hash)
        @hash = HashWithIndifferentAccess.new(hash)
      end
      def method_missing(name)
        return hash[name] if hash.key? name
        raise KeyError.new("Attribute not found: #{name}")
      end
    end
  end

  module ExampleGroupMethods
    def it_returns_status(status)
      it 'returns the correct status' do
        expect(last_response.status).to eql(status)
      end
    end

    def it_returns_attributes(resource:, model:, only: [], modifier: nil)
      it "expects returned resource to have the following model's attributes" do
        @api_resource = objectize_resource(last_response.body, root: resource)

        @model = eval(model)
        if @model.is_a? Hash
          @model = object_hash(@model)
        end

        if only
          only.each do |attribute|
            if modifier
              expect(@api_resource.send(attribute)).to(
                eql(@model.send(attribute).send(modifier.to_sym))
              )
            else
              expect(@api_resource.send(attribute)).to eql(@model.send(attribute))
            end
          end
        end
      end
    end
    alias_method :it_returns_db_model, :it_returns_attributes
    alias_method :it_returns_more_attributes, :it_returns_attributes

    def it_includes_in_headers(headers: {})
      it 'returns the correct headers' do
        headers.each do |header, value|
          expect(last_response.headers[header.to_s]).to eq(eval(value))
        end
      end
    end

    def it_returns_the_resources(root:, number:)
      it 'returns the correct number of data in the body' do
        users = objectize_resources(last_response.body, root: root)
        expect(users.length).to eql(number)
      end
    end
  end


  def self.included(receiver)
    receiver.extend         ExampleGroupMethods
    receiver.send :include, ExampleMethods
  end
end

RSpec.configure do |config|
  config.include RspecApiHelper, type: :api #apply to all spec for apis folder
end

users_spec.rb

#rspec/apis/users_spec.rb
require 'rails_helper'

describe Api::V1::UsersController, type: :api do
  context :index do
    before do
      create_and_sign_in_user
      5.times{ FactoryGirl.create(:user) }

      get api_v1_users_path, format: :json
    end

    it_returns_status(200)

    it_returns_the_resources(root: 'users', number: 5+1)
  end

  context :create do
    before do
      @user = FactoryGirl.attributes_for(:user)

      post api_v1_users_path, user: @user.as_json, format: :json
    end

    it_returns_status(201)

    it_returns_attributes(resource: 'user', model: '@user', only: [
      :email, :first_name, :last_name
    ])

    it_returns_more_attributes(
      resource: 'user',
      model: 'User.last!',
      only: [:updated_at, :created_at],
      modifier: 'iso8601'
    )
  end

  context :show do
    before do
      create_and_sign_in_user
      @user = FactoryGirl.create(:user)

      get api_v1_user_path(@user.id), format: :json
    end

    it_returns_status(200)

    it_returns_attributes(resource: 'user', model: '@user', only: [
      :email, :first_name, :last_name
    ])

    it_returns_more_attributes(
      resource: 'user',
      model: '@user',
      only: [:updated_at, :created_at],
      modifier: 'iso8601'
    )
  end

  context :update do
    before do
      create_and_sign_in_user
      @user = FactoryGirl.create(:user)
      @user.first_name = 'Another name'

      put api_v1_user_path(@user.id), user: @user.as_json, format: :json
    end

    it_returns_status(200)

    it_includes_in_headers(headers: {Location: 'api_v1_user_path(@user.id)'})

    it_returns_attributes(resource: 'user', model: '@user', only: [
      :email, :first_name, :last_name
    ])

    it_returns_more_attributes(
      resource: 'user',
      model: '@user',
      only: [:updated_at, :created_at],
      modifier: 'iso8601'
    )
  end

  context :delete do
    context 'when the resource does NOT exist' do
      before do
        create_and_sign_in_user
        @user = FactoryGirl.create(:user)

        delete api_v1_user_path(rand(100..1000)), format: :json
      end

      it_returns_status(404)
    end

    context 'when the resource does exist' do
      before do
        create_and_sign_in_user
        @user = FactoryGirl.create(:user)

        delete api_v1_user_path(@user.id), format: :json
      end

      it_returns_status(204)

      it 'actually deletes the resource' do
        expect(User.find_by(id: @user.id)).to eql(nil)
      end
    end
  end
end