Hobbes Framework for Page / Component Testing

I am exploring Hobbes Framework to automate my test cases for Page / Components .I am stuck in finding the DOM element ID .Any help is much appreciated .

Sample Code where DOM ID from AEM Hobbes Example :-

new hobs.TestSuite("Home Page Test Suite", {path:"/etc/clientlibs/myTests/myFirstTest/myTestSuite.js"})

.addTestCase(new hobs.TestCase("Navigate to home page")

   .navigateTo("/content/geometrixx-outdoors/en.html"))

.addTestCase(new hobs.TestCase("Hover Over Topnav")

             .mouseover("li.topnav-item-1"))

.addTestCase(new hobs.TestCase("Click Topnav Link")

             .click("li.topnav-item-1 a"));

How to get "li.topnav-item-1" element Id ?

Is there any script which will automate events like Page publish / drag &drop components , dialog authoring ...