node.js - 删除多个引用

Question

我有一个关于删除多个引用的问题。我有 3 个模式模型 -> 事件、帖子和评论。事件存储对帖子的引用(一对多)和帖子存储对评论的引用(一对多)。

<小时/>

事件架构

const mongoose = require('mongoose'),
  Schema = mongoose.Schema,
  ObjectId = mongoose.Schema.Types.ObjectId;

const EventSchema = new Schema({
  organizer: { 
    type: ObjectId, 
    required: true, 
  }, 
  date: { 
    start: { 
      type: Date, 
      required: true, 
    }, 
    end: { 
      type: Date, 
      required: true, 
    }, 
  }, 
  name: {
    type: String,
    required: true,
  },
  description: {
    type: String,
    required: true,
  },
  category: {
    type: String,
    required: true,
  },
  posts: [{
    type: ObjectId,
    ref: 'Post',
  }],
});

module.exports = mongoose.model('Event', EventSchema);

<小时/>

发布架构

const mongoose = require('mongoose'),
  Schema = mongoose.Schema,
  ObjectId = mongoose.Schema.Types.ObjectId;

const PostSchema = new Schema({
  author: {
    type: String,
    required: true,
  },
  date: {
    type: Date,
    default: Date.now(),
    required: true,
  },
  content: {
    type: String,
    required: true,
  },
  comments: [{
    type: ObjectId,
    ref: 'Comment',
  }],
});

module.exports = mongoose.model('Post', PostSchema);

<小时/>

评论架构

const mongoose = require('mongoose'),
  Schema = mongoose.Schema,
  ObjectId = mongoose.Schema.Types.ObjectId;

const CommentSchema = new Schema({
  author: {
    name: {
      type: String,
      required: true,
    },
    id: {
      type: ObjectId,
      required: true,
    },
  },
  date: {
    type: Date,
    default: Date.now(),
  },
  content: {
    type: String,
    required: true,
  },
});

module.exports = mongoose.model('Comment', CommentSchema);

现在看看这种情况:我正在删除一个事件，因此我还需要删除帖子(简单)和相关评论(ups!)。这是我的问题:如何轻松删除事件及其所有引用(删除事件会自动删除帖子和与此帖子相关的评论)？我真的不知道。感谢您的帮助!

Answer 1

0) 阅读您要删除的事件

cont eventObj = Event.findOne({
  _id: myEventId,
})

1) 获取与要删除的事件相关的所有帖子

const posts = eventObj.posts;

const postObjs = Post.find({
  _id: {
    $in: posts,
  },
});

2) 获取与您要删除的帖子相关的所有评论

   const comments = postsObjs.reduce((tmp, x) => [
      ...tmp,
      ...x.comments,
   ], []);

3)删除所有评论

   Comments.remove({
     _id: {
       $in: comments,
     },
   });

4)删除所有帖子

   Post.remove({
     _id: {
       $in: posts,
     },
   });

5) 删除事件

  Event.remove({
     _id: {
       $in: event,
     },
   });