Ruby on Rails

require 'net/http'
require 'json'

class CpfLookupService
  BASE_URL = 'https://api.cpfhub.io'

  Error   = Class.new(StandardError)
  NotFound = Class.new(Error)

  def self.call(cpf)
    new(cpf).call
  end

  def initialize(cpf)
    @cpf     = cpf
    @api_key = ENV.fetch('CPFHUB_API_KEY')
  end

  def call
    uri = URI("#{BASE_URL}/cpf/#{@cpf}")
    req = Net::HTTP::Get.new(uri)
    req['x-api-key'] = @api_key

    res = Net::HTTP.start(uri.host, uri.port, use_ssl: true) { |h| h.request(req) }
    body = JSON.parse(res.body)

    raise NotFound, body.dig('error', 'code') if res.code == '404'
    raise Error, body.dig('error', 'code')    unless res.is_a?(Net::HTTPSuccess)

    body['data']
  end
end

class CpfController < ApplicationController
  def show
    data = CpfLookupService.call(params[:cpf])
    render json: { data: data }
  rescue CpfLookupService::NotFound
    render json: { error: 'CPF não encontrado' }, status: :not_found
  rescue CpfLookupService::Error => e
    render json: { error: e.message }, status: :unprocessable_entity
  end
end

get '/cpf/:cpf', to: 'cpf#show'