Mongoose 根据某些过滤器从对象数组中删除对象答案

【问题标题】：Mongoose remove objects from array of objects based on some filterMongoose 根据某些过滤器从对象数组中删除对象
【发布时间】：2020-11-21 22:30:00
【问题描述】：

我有这样的架构：

var resortSchema = new mongoose.Schema ({
name: String,
price: String,
reviews: [
    {
        type: mongoose.Schema.Types.ObjectId,
        ref: "Review"
    }
]});


var reviewSchema = new mongoose.Schema({
    rating: {
        // Setting the field type
        type: Number,
        // Defining min and max values
        min: 1,
        max: 5,
        // Adding validation to see if the entry is an integer
        validate: {
            // validator accepts a function definition which it uses for validation
            validator: Number.isInteger,
            message: "{VALUE} is not an integer value."
        }
    },
    // author id and username fields
    author: {
        id: {
            type: mongoose.Schema.Types.ObjectId,
            ref: "User"
        },
        username: String
    },
    // resort associated with the review
    resort: {
        type: mongoose.Schema.Types.ObjectId,
        ref: "Resort"
    }
});

在代码中，我在resorts 文档中填充了reviews 数组，我想从resort.reviews 数组中删除一些特定的评论（基于作者ID）。比如：

resort.reviews.pull({"author.id": someSpecificUserID});
resort.save();

但这不起作用。我该怎么做？

编辑： 我可以按特定用户 ID 找到所有评论，但我不知道如何按度假村过滤。我试过这个：

console.log("req.user._id: " + typeof req.user._id); // object
console.log("req.params.id: " + typeof req.params.id); // string
console.log("ObjectId: " + typeof mongoose.Types.ObjectId(req.params.id));

var resortObjectID = mongoose.Types.ObjectId(req.params.id);

// Get ids of reviews matching a particular author
const reviews = await Review.find({ "author.id": req.user._id, "resort": resortObjectID });
console.log("reviews: " + reviews);     // reviews is []. if I remove "resort": resortObjectID I do get all the reviews of that user in all resorts. But I need to filter to only one resort.

//Pass review ids to $pull     // I am not sure if this works yet
await Resort.updateOne(
    { _id: req.params.id },
    { $pull: { reviews: { $in: reviews.map(x=>x._id) } } },
    { multi: true })

【问题讨论】：

标签： arrays mongodb mongoose pull

【解决方案1】：

由于两个集合 (resort and review) 不同，因此根据其他集合的值从一个集合中提取值根本行不通。因此，您首先必须从 review 集合中获取要删除的评论的 ID，然后将它们传递给 $pull

 1. Get ids of reviews matching a particular author
    
    const reviews = await db.review.find({"author.id": <someSpecificUserID>}, {_id: 1});

 2. Pass review ids to $pull

    await db.resort.update(
    { },
    { $pull: { reviews: { $in: reviews.map(x=>x._id) } } },
    { multi: true })

【讨论】：

并非如此。我编辑了原始帖子并添加了更多代码。