uwsgi Websocket error: ASYNC call without async mode !!!, IOError: unable to fd to the event queue

<!doctype html>
<meta charset=utf-8>
<title>UWSGI WS test</title>
<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css">
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.26/angular.min.js"></script>
<script>
  angular.module('app', []).controller('Ctrl', function ($scope) {
    this.logMessages = [];

var self = this;

var log = function (msg) {
      self.logMessages.push({date: new Date(), msg: msg});
      $scope.$digest();
    }

<div ng-repeat="msg in ctrl.logMessages.slice().reverse()"><pre>[{{msg.date|date:'mediumTime'}}]: {{msg.msg}}</pre><div>
</body>

https://ajax.googleapis.com/ajax/libs/angularjs/1.2.26/angular.min.js