$msg = array
                  (
                'body'  => 'Test Test',
                'title' => 'Test',
                'click_action' => 'https://google.com/',
                'icon'  => 'smallicon',/*Default Icon*/
                 'sound' => 'mySound'/*Default sound*/
                  );
            $fields = array
                    (
                        'to'        => 'token',
                        'notification'  => $msg
                    );


            $headers = array
                    (
                        'Authorization: key=',
                        'Content-Type: application/json'
                    );
                $ch = curl_init();
                curl_setopt( $ch,CURLOPT_URL, 'https://fcm.googleapis.com/fcm/send' );
                curl_setopt( $ch,CURLOPT_POST, true );
                curl_setopt( $ch,CURLOPT_HTTPHEADER, $headers );
                curl_setopt( $ch,CURLOPT_RETURNTRANSFER, true );
                curl_setopt( $ch,CURLOPT_SSL_VERIFYPEER, false );
                curl_setopt( $ch,CURLOPT_POSTFIELDS, json_encode( $fields ) );
                $result = curl_exec($ch );
                curl_close( $ch );