title: Rails: PayPal Express Checkout Integration in Localhost
body: <p>I don't know, where to start. I'm integrating PayPal Express Checkout in my RoR application in my Localhost server. </p>
  
  <p>Yes, I'm using a gem, <a href="https://github.com/paypal/merchant-sdk-ruby" rel="nofollow noreferrer">merchant-sdk-ruby</a>. </p>
  
  <p>In this integration, I'm trying to follow this working flow:
  <img src="https://i.stack.imgur.com/FRKpC.gif" alt="enter image description here"></p>
  
  <ol>
  <li>set_express_checkout </li>
  <li>get_express_checkout</li>
  <li>do_express_checkout</li>
  </ol>
  
  <p>In <code>set_express_checkout</code> I'm able to generate <code>token</code> successfully and able to redirect to <a href="https://www.sandbox.paypal.com/webscr?cmd=_express-checkout&amp;token=EC-93W211694E768010D" rel="nofollow noreferrer">https://www.sandbox.paypal.com/webscr?cmd=_express-checkout&amp;token=EC-93W211694E768010D</a> here with my generated token. </p>
  
  <p>Inside the method which generates <code>token</code>, I mean in <code>set_express_checkout</code>, I had to provide 3 URL. </p>
  
  <ol>
  <li><strong>ReturnUrl</strong> </li>
  <li>NotifyUrl</li>
  <li>CancelUrl</li>
  </ol>
  
  <p>Isn't it ReturnUrl (a URL of my application <strong>(which in localhost)</strong> with <code>token</code> and <code>payerID</code>) in which PayPal redirects after generating Checkout Details? </p>
  
  <p>My Question is:
  <strong>Does PayPal redirects in a specific URL of my Application which is hosted on my Local Server?</strong></p>
  
  <p>Please help to integrate PayPal Express Checkout in my localhost.</p>