如何使用填充在猫鼬中

Question

当我收到用户并显示拥有用户的所有实体时，我正在尝试显示所有信息。

我的想法是用户有多个地图，其中一个地图有一个信息与params。

当我在地图路线中通过id获取地图时，请填写show me info properties，但是当我在用户路线上使用populate时，请显示_id。

当我得到一个用户时，如何使用populate显示我的信息属性???

// Get User by id
app.get('/:id', (req, res) => {

    var id = req.params.id;

    User.findById({_id: id})
    .populate('maps')
    .populate('info')
    .exec((err, user) => {

        if (err) {
            return res.status(500).json({
                ok: false,
                message: 'Error finding user'
            });
        }

        if (!user) {
            return res.status(404).json({
                ok: false,
                message: 'User with id ' + id + ' doesnt exist'
            });
        }

        return res.status(200).json({
            ok: true,
            user: user
        });
    });
});

回应：

{
    "ok": true,
    "user": {
        "maps": [
            {
                "visible": true,
                "crossOrigin": "",
                "layer": "",
                "url": "",
                "matrixSet": "",
                "format": "",
                "projection": "",
                "paramsformat": "",
                "paramsversion": "",
                "paramslayers": "",
                "paramsstyles": "",
                "_id": "5b10f594f962fd1d109ea1d5",
                "id": 0,
                "owner": "5b10f57df962fd1d109ea1d4",
                "name": "",
                "keyName": "",
                "type": "map",
                "zIndex": "0",
                "__v": 0,
                "info": "5b10f5f2f962fd1d109ea1d7"
            }
        ],
        "_id": "5b10f57df962fd1d109ea1d4",
        "id": 0,
        "name": "User",
        "email": "user@test.com",
        "password": "user",
        "__v": 1
    }
}

用户模型：

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var userSchema = new Schema({
    id: { type: Number, required: true },
    name: { type: String, required: true },
    email: { type: String, unique: true, required: true },
    password: { type: String, required: true },

    maps: [{ type: Schema.Types.ObjectId, ref: 'map'}]
});
module.exports = mongoose.model('user', userSchema);

地图模型：

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var mapSchema = new Schema({
    id: { type: Number, required: true },
    owner: { type: Schema.Types.ObjectId, ref: 'user'},
    name: { type: String, required: true },
    keyName: { type: String, required: true },
    type: { type: String, required: true },
    visible: { type: Boolean, required: true, default: true },
    zIndex: { type: String, required: true },
    crossOrigin: { type: String, required: false, default: '' },
    layer: { type: String, required: false, default: '' },
    url: { type: String, required: false, default: '' },
    matrixSet: { type: String, required: false, default: '' },
    format: { type: String, required: false, default: '' },
    projection: { type: String, required: false, default: '' },
    paramsformat: { type: String, required: false, default: '' },
    paramsversion: { type: String, required: false, default: '' },
    paramslayers: { type: String, required: false, default: '' },
    paramsstyles: { type: String, required: false, default: '' },

    info: { type: Schema.Types.ObjectId, ref: 'info' }
});
module.exports = mongoose.model('map', mapSchema);