var tasks = [
  {
    id: 'Task 1',
    name: 'Redesign website',
    start: '2016-12-28',
    end: '2016-12-31',
    progress: 20,
    dependencies: 'Task 2, Task 3',
    custom_class: 'bar-milestone' // optional
  },
  ...
]
var gantt = new Gantt("#gantt", tasks);