blog_rails_api_auth_pt_1_10.rb

# app/controllers/v1/users_controller.rb

def create
  user = SignUpUser.perform(user_params)

  if user.save
    render json: user, serializer: AuthenticationSerializer, root: :user
  else
    render json: { errors: user.errors.full_messages },
           status: :unprocessable_entity
  end
end