Cannot access cookies in Chrome, works properly in Firefox

Question

Basic situation and basic relevant info: I have a php code that executes before the opening <doctype> tag. The hope was to (if necessary) send a redirect based on user's browser's language preferences before anything else loads.

The script attempts to do two things based on highest supported language preference:

1. Use php: setcookie() to create a cookie with the two-letter language code.
   • Example cookie name = value: x_language = es
2. Use php: header("Location: " . $requestedSite); to redirect to a subdomain,
   • Example domain: es.domain.com

Example:

if (isset($_COOKIE['x_language'])) {
    -Determine correct subdomain based on cookie value-
    -If not currently on that subdomain, redirect to it-
} else {
    setcookie('x_language','es',time() + 31536000 ,'/','.domain.com' );
    header("Location: " . $requestedSite);
}

The problem: Firefox works perfectly. Chrome (and other browsers) fail to recognize the cookies at all.

I've boiled it down to this:

• print_r($_COOKIE) works properly in Firefox, and returns a lovely, populated array.
• print_r($_COOKIE) fails in Chrome, and returns an empty array.

This is the core of the problem, my function doesn't recognize the existence of a cookie because Chrome doesn't.

• I've made sure every browser accepts cookies.
• I've checked dev tools to make sure the cookie is in place on all browsers, (it is).
• I realize a cookie's value isn't available until the next page load, but that isn't an issue here. Even after it is set, it won't read.
• There is no output above the initial setcookie();

So how do I get Chrome (and other browsers) to recognize its own cookies?! Does anyone know why this would all work flawlessly on Firefox but fail elsewhere?

---

On a lark I decided to try this. I created a file that only contains:

<?php
print_r($_COOKIE);
?>

Again, I see the cookie array in Firefox. Meanwhile, in Chrome, IE, Opera, Safari, I get an empty array. Could this be a server issue?

Answer 1

OP returns with answer:

Alright, I'm adding this as an 'Answer' in case anyone else comes across this (totally bizarre) behavior and lands here:

It turns out my hosting provider was doing some seriously aggressive caching with my WordPress site that I was unaware of.

At the time I posted my question, I didn't think being on WordPress was relevant, but apparently it was.

Basically it was doing this:

---

With a clean Cache:

• Visitor 1 visits the site.
• The php processes and produces output as expected.

• Visitor 1 is served php output (based on his browser's parameters and such).

• Visitor 2 visits the site. Visitor 2 sees *Visitor 1's version of the site.

The php is processed once and only once per Cache-clear.

This caching behavior meant that accessing cookies through php was simply not going to work right, but accessing them with Javascript WOULD work.

(Important note: It turns out the above-stated caching behavior is disabled for any user viewing the site while logged into wordpress, and this is common behavior for WordPress Cache plugins. That is why I was seeing different behavior in Firefox than I saw in other browsers, because I was actively logged in with Firefox. This could be a helpful piece of information for someone out there.)

---

My solution:

Use Javascript to run an AJAX query to a .php file which would process the language preferences of the visitor and return the output as a 2-character code, (i.e. 'en' 'es' 'pt' 'de', etc).

Using AJAX to call php allowed me to use php's server-side access to a browser's language preferences while circumventing the super-agro caching of my host.

I hope this helps someone! And thanks to everyone who tried to help me out with this.