gistfile1.js

var old_data;

//Presentations
function presentations()
{
	$.ajax({
	  url: '/jsonapi/presentations/',
	  type: 'POST',
	  dataType: 'json',
	  complete: function(xhr, textStatus) {
	    setTimeout("presentations()", 5000);
	  },
	  success: function(data, textStatus, xhr) {
	  
    if(data === old_data){
      // do nothing
    } else {
      old_data = data;
      
      console.log('Checking presentations');
  		var item_list = '';
  		for (var i=0; i < good_data.length; i++) {

  			var thumbnail = '<div class="thumbnail"><img src="/static/img/default_avatar.png" /></div>';
  			var title = '<span class="title">' + data[i].name + '</span>';
  			var author = '<span class="author">' + data[i].user + '</span>';
  			var twitter_name = '<span class="twitter_username">@' + data[i].twitter_name + '</span>';
  			var content = '<div class="content">'+ title + author + twitter_name + '</div>';

  			var countdown = (data[i].status == 'ongoing' ? '<div class="countdown">9:38</div>' : '');

  			var item = '<li class="'+ data[i].status +'">'+ thumbnail + content + countdown + '</li>';

  			item_list += item;

  			var now = new Date();
  			var endingSoon = new Date(now);
  			endingSoon.setMinutes(now.getMinutes() + 1);
  			// $(".ongoing .countdown").countdown(endingSoon,
  			// 	{
  			// 		precision: "simple"
  			// 	}
  			// );

  		};
    }
    
		console.log(item_list);
		console.log($("#presentations ul").html());
		if($("#presentations ul").html() == item_list)
		{
			console.log('No change in presentation');
		}
		else
		{
			console.log('Presentations changed');
			$("#presentations ul").html(item_list);
		}
		
		
	  },
	  error: function(xhr, textStatus, errorThrown) {
	    //called when there is an error
	  }
	});
}

presentations();