7 创建schema的技巧

在egg.js中：

    const UserSchema = new Schema({
        userId: { type: String  },
        userName: { type: String  },
        userPwd: { type: String  },
        cartList: [
            {
                ...goodsItem,
                productNum:{
                    type:Number,
                    default:1
                }
            }
        ],
    });

goodsItem.js

module.exports = goodsItem = {
    productId: { type: String  },
    productName: { type: String  },
    salePrice: { type: Number  },
    productImage: { type: String  },
}