Facebook Messenger API: Trouble setting up a webhook

Question

I am trying to set up a web hook for the new Facebook Messenger bot platform on my PHP webserver and am receiving this error:

The URL couldn\'t be val

Answer 1

I came across a fix. I scrapped my js attempt and created a new php file with the following code:

I got this code from the first 10 minutes of this video: https://www.facebook.com/marketingdevelopers/videos/883648801749520/