Configure RSpec Ruby on Rails API mode with Serializer and Factory Bot, part 2

In Rails, the serializer allows you to customize the data instead of having a default rendering.

In this article, we’ll look at a step-by-step guide to using serializers in your applications. The following is the implementation of Rspec in the Serializer.

1. Add serializer gem to Gemfile

gem 'active_model_serializers'

go back to terminal and run

 bundle install 

2. create a serializer file

 bundle exec rails g serializer Customer

edit app/serializers/customer.rb add validation

 class Customer < ActiveModel::Serializer  
  attributes :name, :email
 end  

In the example file above, the response in the client json will show the name and email attributes.

function The serializer file itself can be used to customize the response based on the front-end response requirements.

3. Install the factory robot

Add the Gem Factory bot to Gemfile in the :development, :test group

gem 'factory_bot_rails'

4. Configure Factory Bot

In connection with the previous tutorial in this tutorial, we still use the Customer.rb model.

then open terminal to create factory file in rspec folder by running command

rails g factory_bot:model customer

After running the above command, a file like this will be automatically created

after creating the spec/factories/customers.rb file

configure factory customer.rb file as below

FactoryBot.define do 
  factory :customer do |f|
    f.name {Faker::Name.name}
    f.email {Faker::Internet.email}
   end
end 

5. Configure RSpec with Serializer and Factory Bot

add folders and files like this spec/support/serializer_spec_helper.rb

then add the line of code like below

module SerializerSpecHelper
  def serialize(obj, opts={})
    serializer_class = opts.delete(:serializer_class) || "#{obj.class.name}Serializer".constantize
    serializer = serializer_class.send(:new,obj)
    adapter = ActiveModelSerializers::Adapter.create(serializer, opts)
    adapter.to_json 
  end  
end 

Configure RSpec configuration with factory bot, add spec/support/factory_bot.rb file

then add the code below

RSpec.configure do |config|
 config.include FactoryBot::Syntax::Methods  
end 

Add the code below to the spec/rails_helper.rb file, so that RSpec can detect files in the support/ and serializer_spec_helper.rb folders.

 Dir [Rails.root.join('spec', 'support', '**', '*.rb'].sort.each { |f| require f}
 RSpec.configure do |config| #sisipkan kode dibawah 
 config.include SerializerSpecHelper, type: :serializer 

6. Configure Skenario Test RSpec and FactoryBot serializer

[
  {
        "name": "Persada Ersad",
        "email": "ersad@doterb.com"
    }
]

Add the code below to the spec/serializers/customer_serializer_spec.rb folder and file

require 'rails_helper'  
 RSpec.describe CustomerSerializer, :type => :serializer do
  customer = FactoryBot.create(:customer)
  serializer = CustomerSerializer.new(customer)
  describe 'attributes' do
    it { expect(serializer).to include(:name, :email) }

    it 'returns data should be contain name and email' do
      expect(serializer).to include(
        name: customer.name,
        email: customer.email
      )
    end
  end
end 

Then go back to the terminal and type the command

rspec

We are trying to train if there are data errors in the CustomerSerializer response

in the app/serializers/customer_serializer.rb file remove the ‘:email’ code

class CustomerSerializer < ActiveModel::Serializer
  attributes :name
end

Then go back to the terminal and type the command

rspec

the result will be a fail test as below:

Good luck and congratulations 😀

Tutorial created by: Doterb | Persada Ersad