Authenticate with the Trello API

trello-authenticate.html

   <script src="https://api.trello.com/1/client.js?key=MY_KEY"></script>

    <script type="text/javascript">
      Trello.authorize({
        name: "My site",
        scope: {
          read: true,
          write: false
        },
        expiration: "never",
        error: function() {
          console.log("Failed authentication");
        }
      });
    </script>