function sendMessage($mesaj){
        $content = array(
            "en" => $mesaj
            );
        
        $fields = array(
            'app_id' => "$APP IDIYI BURAYA GİR",
            'included_segments' => array('All'),
            'data' => array("foo" => "bar"),
            'contents' => $content
        );
        
        $fields = json_encode($fields);
        print("nJSON sent:n");
        print($fields);
        
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, "https://onesignal.com/api/v1/notifications");
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/json; charset=utf-8',
                                                   'Authorization: Basic API KEYİ BURAYA GİR'));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
        curl_setopt($ch, CURLOPT_HEADER, FALSE);
        curl_setopt($ch, CURLOPT_POST, TRUE);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $fields);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);

        $response = curl_exec($ch);
        curl_close($ch);
        
        return $response;
    }