config.js

/**
 *
 */
window.onload = function() {

    $('#pluginFlyvemdm-mqtt-test').on('click', function() {
        data = $("#pluginFlyvemdm-config input,#pluginFlyvemdm-config select").serialize();
        posting = jQuery.post('../ajax/mqtt_test.php', data, 'json');
        posting.done(function(data) {
         var successIcon = ' OK';
         var failIcon = ' KO';
            var feedback = $.parseJSON(data);
         if (feedback.status == "Test message sent") {
             $('#pluginFlyvemdm-test-feedback').empty().append(successIcon);
         } else {
            $('#pluginFlyvemdm-test-feedback').empty().append(failIcon);
         }

        });
        return false;
    });
};