function glip_webhook($webhook_url,$title, $body, $activity,$icon ='' ) {

$json = json_encode(array('icon'=>$icon,'activity'=>$activity,'title'=>$title,'body'=>$body) );

$ch = curl_init($webhook_url);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_POSTFIELDS, $json);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
    'Content-Type: application/json',
    'Content-Length: ' . strlen($json))
);
$r = curl_exec($ch);
return $r;
}