Run PHP script without webpage waiting for it to f

Question

I have some basic website tracking software that sends a JSON object with jQuery AJAX from a webpage cross-domain to a server where the data is processed by a php script. This is triggered on window.onbeforeunload.

When benchmarking my php script I have realised that the client website on a different domain is still waiting for the php script to finish running before loading the next page. For example, a visitor to a client site navigates to another page. We send the JSON object cross domain to the server to process it. If I add sleep(30); to my php script the client website will not load the next page until this php script finishes (30+ seconds).

I do not need to return any values after running this script so how can I ensure this php script runs without having any impact on the client site?

I hope I've explained myself well enough. Ask any questions if I haven't, thanks.

SOLUTION:

This is what worked for me (http://php.net/manual/en/features.connection-handling.php#93441):

ob_end_clean();
header("Connection: close\r\n");
header("Content-Encoding: none\r\n");
ignore_user_abort(true); // optional
ob_start();
echo ('Text user will see');
$size = ob_get_length();
header("Content-Length: $size");
ob_end_flush();     // Strange behaviour, will not work
flush();            // Unless both are called !
ob_end_clean();

//do processing here
sleep(5);

echo('Text user will never see');
//do some processing

Answer 1

• For PHP-fpm:

  To close connection with client (send response), but continue running script and processing some data, this function can help you - fastcgi_finish_request

• For apache:

  See this link - close a connection early