A sample for how to receive webhook calls from the BreweryDB API. This code comes with no guarantees and hasn't been thoroughly tested.
This is a very simple PHP script you could use to just receive a web hook call.
You'd put this somewhere where it can be accessed via the outside world (i.e. - http://mywebsite.com/webhookreceiver.php) and register it in your developer dashboard on http://brewerydb.com (note that web hooks are only available to premium subscribers).
Then the BreweryDB API will send a POST to that URL when something changes in the API and you can process the data like below. What you do with the information depends on your specific needs.