angluarjs嵌套ajax调用 Promise写法

Question

如何用Promise解决嵌套ajax调用?

$ionicLoading.show({template: '校验信息中...'});
$http.post('/API/ClientAuthorize/GetUserByOpenID',{OpenID: openId})
    .success(function(json){
            if(json['ErrCode'] == 0){
                $ionicLoading.show({template: '提交订单中...'});
                $http.post('/API/ClientBooking/MakeBooking', {
                    name: json.Data.name,
                    phone: json.Data.phone,
                    date: '2017-01-13'
                })
                .success(function(json){
                    if(json['ErrCode'] == 0){
                        $state.go('xxx', {id: json.Data.id});
                    }
                    else{
                        alert(json['errMessage']);
                    }
                })
                .error(function(){
                     $ionicLoading.show({
                        template:'网络环境欠佳，请稍后重试', 
                        noBackdrop: true, 
                        duration: 1000
                    });
                })
            }
            else{
                $ionicLoading.hide();
                alert(json['ErrMessage'])
            }
    })
    .error(function(){
        $ionicLoading.show({
            template:'网络环境欠佳，请稍后重试', 
            noBackdrop: true, 
            duration: 1000
       });
    })