<div ng-controller="opcuaClientController as vm">
    <div class="panel-content" style="padding: 10px;">
        <div ng-if="!vm.connected">
            <input type="text" ng-model="vm.url"><br>
            <button class="btn btn-default" ng-click="vm.connect()">Connect!</button>
        </div>
        <div ng-if="vm.connected">
            <button class="btn btn-default" ng-click="vm.getNodes()">Get nodes!</button>
            <button class="btn btn-default" ng-click="vm.subscribe()">Subscribe to nodes!</b