title: How to get http request origin in php
body: <p>I want to create an API, and to authenticate API consumers, I will provide an API KEY, App-id and App-Secret. The problem is that I want to know where the http Request is coming from, so that I can know if the Host that is making que request is the registered Host. For example : www.someone.com has an app-id :0001, app-secret:1200 and api-key:458. If this credentials are used to make A request, I want to know if the requester is really www.someone.com</p>