How to use HTTP_REFERER in PHP

Question

I know this may be a duplicate of another link on here but I am not able to find a fix for my code.

I am trying to make a puzzle for my friends and family can try to do and I need a way to track what website they just came from so I know whether to send them to the next puzzle/win screen, or to send them to a page effectively saying they are cheaters. I am trying to use $_SERVER[HTTP_REFERER] to make this easier for me, but I want to echo out the address that the user is coming from to test my code, and I keep getting an index error.

MY CODE:

<?php
$_SERVERADDR=$_SERVER['HTTP_REFERER'];
echo "$_SERVERADDR";
?>

I keep getting an index error on this line $_SERVERADDR=$_SERVER['HTTP_REFERER'];

Can anyone help out?

What do you get if you `echo "
".print_r($_SERVER,1)."
;"`? I mean, you are seeing the $_SERVER object? — Kinglish, May 13 '21 at 15:48
@JohnTyner I put the information here: https://pastebin.com/cR5m2c5u — Michael Pate, May 13 '21 at 15:58

score 1 · Accepted Answer · answered May 13 '21 at 15:59

https://stackoverflow.com/a/60288899/7044855

Referrer isn't always set. You can set HTTP headers manually if you're testing using curl/postman/etc, but not if you were testing by simply hitting your script in a browser.

Using this key/value combination you should see the following output

<?php

$referer = $_SERVER['HTTP_REFERER'];

echo $referer;
// https://google.com

How to use HTTP_REFERER in PHP

1 Answers1