Mongoose 填充子文档

Question

我有一个orderSchema 有一个subdoc productOrder：

const paymentTrans = require('./PaymentTrans').schema;
const productOrder = require('./ProductOrder').schema;

const orderSchema = new mongoose.Schema({
    orderId: { type: mongoose.Schema.Types.ObjectId },
    userId : {type: mongoose.Schema.Types.ObjectId, ref: 'User'},
    productOrder: [productOrder],
    totalPerOrder: {type: Number, default:''},
    paymentTrans: [paymentTrans]
}, { timestamps: true });

const Order = mongoose.model('Order', orderSchema);

module.exports = Order;

产品订单架构

const productOrderSchema = new mongoose.Schema({
    sku: { type: String, default: '' },
    name: { type: String, default: '' },
    quantity: { type: Number, default: '' },
    price: { type: Number, default: '' },
    total: { type: Number, default: '' }
});

const ProductOrder = mongoose.model('ProductOrder', productOrderSchema);

module.exports = ProductOrder;

我希望从order（orderSchema）得到productOrder：

试过这些

Order.findById(req.body.id)
        .exec(function (err, products) {
            var opts = {
                path: 'productOrder',
                model: 'ProductOrder'
            };

            Order.populate(products, opts, function (ree, products) {
                console.log(JSON.stringify(products));
            });

            res.render('store/cart', {
                title: 'MyCart',
                angularApp: 'storeApp',
                products: products
            });
        });

其中req.body.id 是orderId，console 中的object 如下所示：（抱歉，WebStorm 不能从控制台复制/粘贴）

我尝试过的另一种方法

Order.findById(req.body.id, function (err, products) {
        var opts = [
            { path: 'productOrder',  model: 'ProductOrder' }
        ]

        Order.populate(products, opts, function (err, products) {
            console.log(products);
        })
    })

还有一个

Order.find({ _id: req.body.id, userId: req.user._id })
        .populate({
            path: 'productOrder',
            populate: {
                path: 'productOrder',
                model: 'ProductOrder'
            }

        })
        .exec(function (err, productOrder) {
            //products.forEach(function(elem){
                console.log("products = " + JSON.stringify(productOrder));
            //});

            console.log("REQ._ID " + req.body.id);
            res.render('store/cart', {
                title: 'MyCart',
                angularApp: 'storeApp',
                products: productOrder
            });
        });

他们最终都给了我整个订单的doc。 我怎样才能只得到订单的产品？ (productOrder) 谢谢

Answer 1

您可以使用select 函数然后填充如下

Order.findOne({ _id: req.body.id})
    .select('-_id productOrder')
    .populate('productOrder')
    .exec(function (err, orderObj) {
      if(!err) {
        var productOrder = orderObj.productOrder;
        //products.forEach(function(elem){
            console.log("products = " + JSON.stringify(productOrder));
        //});

        console.log("REQ._ID " + req.body.id);
        res.render('store/cart', {
            title: 'MyCart',
            angularApp: 'storeApp',
            products: productOrder
        });
      }
    });