匹配猫鼬填充中的特定值

Question

以下是用户集合的架构：

const Mongoose = require('mongoose')

const Schema = Mongoose.Schema

const userSchema = new Schema({
    name: {
        type: String,
        required: true
    },
    email: {
        type: String,
        required: true
    },
    password: {
        type: String
    },
    supporterOf: [{
        type: Schema.Types.ObjectId,
        ref: 'individual',
        required: false
    }],
})

module.exports = Mongoose.model('user', userSchema);

我想填充“supporterOf”，它是个人的集合（参考：个人）。'supporterOf' 包含一个 ObjectId 数组。我遇到了将特定 objectId 与该 ObjectId 数组匹配的问题。谁能建议我如何将特定的 ObjectId 与填充函数中的 ObjectIds 数组匹配？

Answer 1

You have a reference of 'individual' in supporterOf and you want to populate only relevant object from the array of individuals? If this is right case then do the following:

YourUserModel.findById(userId, function (err, user) {
        console.log(user)
     }).populate({
        path: 'supporterOf',
        match: {
           yourObjectOfIndividualDocument: yourMatchingIdOfIndividual
        }
     })
     .exec()

Replace yourObjectOfIndividualDocument: yourMatchingIdOfIndividual by name: 'abcd'. Here name is the field of Individual document not of User document.