live_banners.rb

<div class="container container-fluid">
  <ul class="list-group" id="banners"></ul>
</div>
<script>
var json;
var source = new EventSource('/api/live_banners'); 
source.onmessage = function(evnt) { 
  json = JSON.parse(evnt.data);
  addBanner(json);
}
var banner;
var banners = document.getElementById("banners")
function addBanner(data) {
  banner = document.createElement("li");
  banner.setAttribute("class", "list-group-item" );  
  banner.appendChild(document.createTextNode(JSON.stringify(data)));
  banners.appendChild(banner);  
}
</script>