PHP provides a fancy way of opening and including files directly over HTTP, which they call "URL wrappers". As tempting as it may seem, in the long run doing remote opens with URL wrappers is not the best practice. So here's what I came up with when needing to do this kind of caching thing in my own scenarios. It requires you have the cURL module installed and that the webserver can read and write from /tmp.
It often happens that when you're building a web page or app, you may want to include some content from a remote server. Say that it's some statistic figure that the remote outputs as HTML or TXT and you then want to retrieve it and either do something with it or directly display as part of your own page. And you're working in PHP.
They provide the short script that does the work inside a function (easy to drop into a class), and grabs the remote file, and pulls down to /tmp for the script to use. It even allows you to specify a timeout for the file, forcing the script to grab a new copy every so often...
