old_contents: angular.module('landingApp', [])
  .controller('landingController', ['$scope', '$window', function($scope, $window) {
    var host = "ws://" + $window.location.host + "/userwebsocket"
    ws = new WebSocket(host);
    ws.onmessage = function(e) {
      $scope.cameraInfo = JSON.parse(e.data);
      $scope.$apply();
    };
  
    $scope.changeChk = function(cameraInfo, status) {
      cameraInfo.status = status;
      ws.send(JSON.stringify(cameraInfo));
    };
  }]);
new_contents: angular.module('landingApp', [])
  .controller('landingController', ['$scope', '$window', function($scope, $window) {
    var host = "ws://" + $window.location.host + "/userwebsocket"
    ws = new WebSocket(host);
    ws.onmessage = function(e) {
      $scope.cameraInfo = JSON.parse(e.data);
      $scope.$apply();
    };
  
    $scope.changeChk = function(cameraInfo, status) {
      cameraInfo.status = status;
      ws.send(JSON.stringify([cameraInfo]));
    };
  }]);
subject: send data in array format