Updating text within nested model

I have just started learning the MERN stack and I am having trouble updating a text within a model. I appreciate any tips/comments!

I am working with 2 models, with the comments model embedded within the cats models like so.

const mongoose = require(“mongoose”);

const Schema = mongoose.Schema;

const commentSchema = new Schema(


user_id: { type: String, required: true },

cat_id: { type: String, required: true },

text: {

  type: String,

  min: [3, "Comment cannot be too short"],


email: { type: String, required: true },


{ timestamps: true }


const Comment = mongoose.model(“Comment”, commentSchema);

module.exports = Comment;

And this is within the cat models

const mongoose = require(“mongoose”);

const Schema = mongoose.Schema;

const Comment = require(“./comments.js”);

const catSchema = new Schema(


name: {

  type: String,

  required: true,

  unique: true,

  min: [2, "Cat name minimum of 2 characters."],


description: { type: String, required: true },

image: { type: String },

comments: [Comment.schema],


{ timestamps: true }


const Cat = mongoose.model(“Cat”, catSchema);

module.exports = Cat;

In my controller, when I update a comment, I need to update the respective comment inside the cat model too, but I’m not able to do so. I tried targeting the particular cat, foundCat, and I can’t access the comment with foundCat.comments.id(req.params.id)

Strangely enough, when I console log “foundCat.comments.id”, it tells me that this is a function? So I don’t know why I can’t access and update that text…

Here is my code:

Comment.findOne({ _id: req.params.id }, (err, comment) => {

if (err) {

  return res.status(404).json({


    message: "Comment not found!",




// update the comment details

comment.text = req.body.text;

// save the updated comment



  .then(() => {

    // return json response if successful

    return res.status(200).json({

      success: true,

      id: comment._id,

      message: "Comment updated!",



  .catch((error) => {

    return res.status(404).json({


      message: "Comment not updated!",



// now update the comment entry for the cat too

Cat.findOne({ _id: comment.cat_id }, (err, foundCat) => {

  console.log("This doesnt work", foundCat.comments.id(req.params.id));

  foundCat.save((err, updatedCat) => {






Example of the comments within a cat:

Hi @Zinc ,

To update a specific elements inside an array you need to use an array filter operator:

Its probably available. In mongoose but you can use a native driver for mean stack.

See this guide