Subdocument function "pull" and "id" not working in Mongoose - node.js

Question

I am pretty new at mongoose and nodejs so I was doing my project referring to mongoose document. I want to remove a particular subdocument in the comment array by identifing the subdocument with its id. I trried doing it using "pull" as well as "id" method as shown in the image. I couldn't find any mistake in my syntax as well but still it is working.
This is sample document from my db:
{
comments: [
{
replyComment: [],
_id: 601a673735644c83e0aa1be3,
username: 'xyz123#gmail.com',
email: 'xyz123#gmail.com',
comment: 'test123'
},
{
replyComment: [],
_id: 601a6c94d1653c618c75ceae,
username: 'xyz123#gmail.com',
email: 'xyz123#gmail.com',
comment: 'reply test'
},
{
replyComment: [],
_id: 601eb7ba7233015d7090c6bf,
username: 'xyz123#gmail.com',
email: 'xyz123#gmail.com',
comment: 'test comment'
},
{
replyComment: [],
_id: 601ec090f5f22d75b41bec7b,
username: 'xyz123#gmail.com',
email: 'xyz123#gmail.com',
comment: 'test comment123'
}
],
_id: 601a3b8038b13e70405cf9ea,
title: 'latest test',
snippet: 'latest test snippet',
body: 'latest test body',
createdAt: 2021-02-03T05:58:24.123Z,
updatedAt: 2021-02-07T06:56:53.902Z,
__v: 15
}
By doing this test findById("601a3b8038b13e70405cf9ea") and console.log(result)
My topicSchema file:
const mongoose = require('mongoose');
const Schema =mongoose.Schema;
const topicSchema = new Schema({
title: {
type: String,
required: true
},
snippet: {
type: String,
required: true
},
body: {
type: String,
required: true
},
comments: {
type: Array,
required: false
}
}, {timestamps: true},{ versionKey: false });
const Topic = mongoose.model('Topic', topicSchema);
module.exports = Topic;
My commentSchema file:
const mongoose = require('mongoose');
const Schema =mongoose.Schema;
const comSchema = new Schema({
username: {
type: String,
required: true
},
email: {
type: String,
required: true
},
comment: {
type: String,
required: true
},
replyComment: {
type: Array,
required: false
},
}, {timestamps: true},{versionKey: false});
const Comm = mongoose.model('comm', comSchema);
module.exports = Comm;

Answer 1

You have not defined topic and don't using topic = result, with , because it's not necessary
so doing like this :
result.comments.id(commId).remove();
result.save()
if you want to using topic just try
let topic = result;
topic.comments.id(commId).remove();
topic.save()
for this document you can using update and $pull like this:
Topic.updateOne(
{
_id: req.params.id,
},
{
$pull: {
"comments" : { _id: req.params.id1 }
},
},
).then((res)=>{
console.log(res)
}).catch(err=>{
console.log(err)
});
if you can use async/await just try
app.delete('/topic/:id/comments/:id1',async(req,res)=>{
let result = await Topic.findById(req.params.id);
result.comments.id(req.params.id1).remove();
let finalResult = await result.save()
console.log(finalResult)
})
and with .then() .catch approach:
Topic.findById(res.params.id).then(result=>{
let topic = result;
topic.comments.id(res.params.id1).remove();
topic.save().then(result=>{
console.log(result)
}).catch(err=>console.log(err))
}
).catch(err=>{
console.log(err)
});
NOTE: update the mongodb to 4.4 and uninstall mongoose module and install again