How to use Gem included when developing Rails API server (rack-cors, rspec-rails, factory_bot_rails, rubocop)

Premise

Building Rails API server environment using docker-compose I didn't mention Gem much in this article, so continue

Editing Gemfile

Install the following Gem.

...
gem 'rack-cors'

group :development, :test do
...
  gem 'rspec-rails', '~> 3.9'
  gem 'factory_bot_rails'
end

group :development do
...
  gem 'rubocop', require: false
end

rack-cors Required when using postman. If you don't do it, a CORS problem will occur and an error will occur.

config > initializers > cors.rb If you write as follows, you can hit the API from anywhere.

cors.rb

Rails.application.config.middleware.insert_before 0, Rack::Cors do
  allow do
    origins '*'

    resource '*',
             headers: :any,
             methods: %i[get post put patch delete options head]
  end
end

rspec-rails, factory_bot_rails Since there is a file that is automatically generated when generating a model or controller, it is better to put it in advance.

rspec-rails GitHub Rails 5 uses 3 series of rspec-rails. (4 ~ in Rails 6)

After bundler install, the initial file below? Installation

rails generate rspec:install
…
      create  .rspec
      create  spec
      create  spec/spec_helper.rb
      create  spec/rails_helper.rb

Also added the following to .rspec and application.rb

See Procedure for installing Rspec and Factory_bot in Rails app

.rspec:.rspec

--color
--require rails_helper
--format documentation

application.rb

    config.generators do |g|
      g.test_framework :rspec,
                       view_specs: false,
                       helper_specs: false,
                       controller_specs: false,
                       routing_specs: false

The model test was automatically generated, The integration test was manually created for writing in Request spec.

spec > requests > hoge_api_spec.rb I named it like this.

The request spec was written with the following configuration

hoge_spec.rb

RSpec.describe 'HogeAPI' do
  describe 'POST #create' do #Show action name
    context 'If xxx' do　#conditions
      before do
        #Prepare dummy data
        FactoryBot.create(:hoge)
        ...
      end

      it 'yy' do
        expect do #When detecting a change in DB
          post '/hoge/create', params: { name: "Hoge" }
        end.to change(Hoge, :count).by(+1) and change(Table2, :count).by(0)
        expect(response.status).to eq(201) #Check the status code
      end
    end

reference

[Rspec] Rails model test basics [Rails] How to write API test Test API using RSpec How to create test data using FactoryBot in Rails project

How to write application.rb that was useless

Since the generators in application.rb just don't want to generate the controller test file to generate the controller, Refer to Everyday Rails-Introduction to Rails Testing with RSpec

application.rb

# NG
    config.generators do |g|
      g.test_framework :rspec,
                       controller_specs: false

At first I wrote, but the controller generation was as expected, but for some reason the model test file could not be generated due to an error.

rubocop Since rubocop is also used when formatting with VS Code, I installed it locally.

It will check if the file is written correctly.

//When you want to check
rubocop

//When you can check and fix it automatically
rubocop -a

It's a very warning, so check the content of the warning and set it to skip if it is unnecessary.

Example

.yml:.rubocop.yml

AllCops:
    Exclude: #Specify the files you want to exclude in Exclude.
      - 'spec/*.rb'
      - 'db/schema.rb'
      - 'test/*'
      - 'config/**/*'
      - 'Gemfile'
      - 'bin/*'


Style/FrozenStringLiteralComment:
    Enabled: false

Style/Documentation:
    Enabled: false

Style/StringLiterals:
    Enabled: false

Metrics/BlockLength:
    Exclude:
        - 'spec/**/*'

Metrics/MethodLength:
    Max: 30

Metrics/AbcSize:
    Max: 30

Style/AsciiComments:
    Enabled: false

AllCops is a setting common to all warnings

reference

Set CORS for API in Rails Let's use RuboCop with Rails option and Lint option