Testing Facebook login with Rspec & Capybara using koala gem- Ruby on Rails

login_using_facebook_spec.rb

require 'rails_helper'
require 'koala'

feature 'Login using facebook' do
  before do
    @test_users_api=Koala::Facebook::TestUsers.new(:app_id =>FB_APP_ID , :secret =>FB_SECRET_KEY)
    @test_user=@test_users_api.create(false)
  end
  after do
    @test_users_api.delete(@test_user["id"])
  end
  scenario 'authenticates successfully' do
    visit root_path
    click_on "Sign In"
    click_on "Login with Facebook"
    fill_in "email",with: @test_user["email"]
    fill_in "pass",with: @test_user["password"]
    click_on "loginbutton"
    find(:xpath, "//button[@name='__CONFIRM__']").click
    expect(page).to have_content("Successfully authenticated from Facebook account.")
  end  
end