PHP check whether Incoming Request is JSON type

Question

Is there anyway to check whether an incoming request is of AJAX JSON type?

I tried

if(($_SERVER[\'REQUEST_METHOD\']==\'JSON\'))
{
}

Answer 1

You would need to set a header from the client side. jQuery and other libraries set a x-requested-with header:

if(strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest')
{
   echo "Ajax request";
}

Answer 2

Try json_decode()

Answer 3

Where are you accepting requests from, exactly, that you wouldn't know?

You could have a function at the beginning of the script that tries to import the data as JSON or simplexml. If it catches an error, you know it's the other one...

On second thought, have it test it to be JSON, simplexml will throw an error for tons of reasons.

 $json_request = (json_decode($request) != NULL) ? true : false;

Answer 4

You can check the X-Requested-With header, some libraries, like jQuery set it to "XMLHttpRequest".

$isAjaxRequest = $_SERVER['X_REQUESTED_WITH'] == 'XMLHttpRequest';

Answer 5

You can do a check on the accept param, if it's text/javascript your talking json, if it's text/xml guess what :P

$_SERVER['HTTP_ACCEPT']

Answer 6

you can always set an extra header specifying that, or use an arbitrary variable to indicate JSON requests.