title: How to check if a user liked a url
body: <p>Suppose that we put like button on the link "http://myshop.com/product/1"</p>
  
  <p>We want to check if a user click liked on this link "http://myshop.com/product/1" or not.
  If user cliked like on this. we will gave some discount for him or give him some reward.</p>
  
  <p>how to do this</p>