使用KeystoneJs进行Mongoose两级人口

时间:2015-08-24 05:09:43

标签: node.js mongodb mongoose keystonejs

我需要用Mongoose / Keystone填充两个级别,但是已经遇到了障碍。

我有3个型号:地区,国家和城市。 地区包含国家和国家/地区包含城市。

我的模特:

模特区域:

var Region = new keystone.List('Region');

Region.add({
      name: {type: Types.Text}
    , countries: {type: Types.Relationship, ref: 'Country', many: true}
});

模特国家

var Country = new keystone.List('Country');

Country.add({
      name: {type: Types.Text}
    , cities: {type: Types.Relationship, ref: 'City', many: true}
});

模范城市

var City = new keystone.List('City');

City.add({
      name: {type: Types.Text}
});

查询:

keystone.list('Region').model.find()
    .populate('countries')
    .exec(function(err, regions){
        console.log(regions)
    });

收率:

    {
        name: 'Oceania',

        countries: [
            {
                _id: 55d9b260415baa6958ac04c1   
                name: 'Australia',
                cities: [
                    _id: 55d9b260415baa6958ac04c2,
                    _id: 55d9b260415baa6958ac04c3,
                    _id: 55d9b260415baa6958ac04c4
                ]
            },

                {
                _id: 55d9b260415baa6958ac04c5
                name: 'New Zealand',
                cities: [
                    _id: 55d9b260415baa6958ac04c6,
                    _id: 55d9b260415baa6958ac04c7
                ]
            }
        ]
    },

    {
        name: 'Americas',
        countries: [
            {
                _id: 55d9b260415baa6958ac04c1   
                name: 'USA',
                cities: [
                    _id: 55d9b260415baa6958ac04d2,
                    _id: 55d9b260415baa6958ac04d3,
                    _id: 55d9b260415baa6958ac04d4
                ]
            },

                {
                _id: 55d9b260415baa6958ac04c5
                name: 'Canada',
                cities: [
                    _id: 55d9b260415baa6958ac04e6,
                    _id: 55d9b260415baa6958ac04e7
                ]
            }
        ]
    }
]

我如何填充城市?据我所知,Mongoose不支持深度人口。

我可以查询结果或如何查询?

1 个答案:

答案 0 :(得分:6)

在猫鼬中你可以这样做:

regionModel.find().populate("countries").exec(function(err, regions){

    if(err){
        throw err;
    }

    // Regions with populate countries
    cityModel.populate(regions, {
        path: 'countries.cities',
        select: '_id name'
    },function(err, regions) {

        //Regions with Countries and Populated Cities

    });

})

其实我不熟悉keystone语法,但我尝试将其转换为keystone语法。希望它有效,如果没有请尝试转换相当于keystonejs的上述代码

keystone.list('Region').model.find()
        .populate('countries')
        .exec(function(err, regions){

            if(err){
                throw err;
            }

            keystone.list('City').model.find()
                    .populate('cities')
                    .exec(function(err, regions){
                        console.log(regions)
                    });

        });