POST Requests seen as GET by server

Got a really strange problem here. When sending post requests to my PHP script

$_SERVER['REQUEST_METHOD']

returns "GET" instead of "POST".

It works fine for every other REST method

so this is what I get

GET -> GET
POST-> GET
PUT -> PUT
DELETE -> DELETE

It only happens on one of my servers so i'm assuming it's an apache problem and i've managed to figure out that it only happens if I add "www" to my url.

I.e

www.something.com

causes the problem but

something.com

does not

I have tested on different sites on the same server and I get the same thing so I'm assuming it's global config.

Any thoughts

Solution

As the HTTP spec says for response codes 301 and 302:

Note: For historic reasons, a user agent MAY change the request method from POST to GET for the subsequent request. If this behavior is undesired, the 307 (Temporary Redirect) status code can be used instead

A third (but unlikely) possibility is you're getting a 303 response to the initial URI. The solution is twofold:

Configure the clients which are under your control to POST to the canonical URI so they are not redirected at all.
Configure your server to redirect using 307 in this case instead of 301/302.