ng-table getData（）函数返回数据但不填充在html中的$ data对象中

Question

我是angularjs和ng-table的新手。使用下面的脚本和html来获取数据。唯一的问题是$data没有填充html。

控制器：

var app = angular.module('main', ['ngTable']);

app.controller('MainCtrl', function($scope, $http, ngTableParams) {
  $scope.tableParams = new ngTableParams({
                page: 1,
                count: 5,
            }, {
                getData: function ($defer, params) {
                    var page = params.page();
                    var size = params.count();
                    var testUrl = 'https://api.github.com/search/repositories';
                    var search = {
                      q: 'angular',
                      page: page,
                      per_page: size
                    }
                    $http.get(testUrl, { params: search, headers: { 'Content-Type': 'application/json'} })
                         .then(function(res) {
                            params.total(res.data.total_count);
                            $defer.resolve(res.data.items);
                        }, function(reason) {
                            $defer.reject();
                        }
                    );
                },
            });
});

HTML：

<link href="https://cdnjs.cloudflare.com/ajax/libs/ng-table/0.3.3/ng-table.min.css" rel="stylesheet"/>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/ng-table/0.3.3/ng-table.min.js"></script>
<div  ng-app="main"  ng-controller="MainCtrl">
   <table ng-table="tableParams" class="table table-striped table-bordered table-hover table-condensed">
        <tr ng-repeat="repo in $data">
            <td data-title="'id'">{{repo.id}}</td>
            <td data-title="'name'">{{repo.name}}</td>
            <td data-title="'owner'">{{repo.owner.login}}</td>
        </tr>
</table> 
<div>

为什么$data没有填充html？