Better way to check if script is running on dev server or prod server

Question

For several years, I have been using the approach usually recommended to check whether a page was invoked locally or remotely by inspecting whether $_SERVER['SERVER_ADDR'] equals 127.0.0.1 or is empty. This has been discussed in other questions, such as this and this. Other superglobals such as $_SERVER['REMOTE_ADDR'] are also often mentioned.

Over time, I have found that this approach sometimes seems to fail.

What I really want to know is whether the script has been invoked on my dev server (xampp, wamp, IDE debugger...) or on a production server. This is so that paths to scripts above the web root can be properly set. While this works 99.999% of the time, it seems that sometimes, when Apache redirects to a 404 page, the $_SERVER['SERVER_ADDR'] must be lost, and a script running on a production server passes the "local" test.

As a result, I am looking for other approaches. Of course I may be doing something wrong in Apache, but regardless, it would be good to have a foolproof test in php.

A couple ideas came to me, and I wonder if these are safe, or whether someone has a better idea.

A. One idea is to look at the current path: something like

define ( 'DEV_SERVER',

           (substr(

                   strtolower($_SERVER['DOCUMENT_ROOT']),

                   0,8)

            =="c:/xampp")
);

B. Another idea would be to check for the existence of a local file with a particular name, but hitting the file system seems like too much work.

Thanks in advance for all insights!

Answer 1

You could also try gethostname().

Although, the best method is probably to only deploy dev specific stuff to dev servers. I.e. keep those scripts separate to your production / regression testing scripts. You don't want these DEV server specific stuff to accidentally become visible to users.