How to update an object inside an array inside another array in a mongoose schema?

Question

found a lot of questions like these here, but not an answer.

Problem

Lets say I have the following mongoose schema:

const mySchema = new mongoose.Schema({
  sanePeoplesField: String,
  comments: [
    normalStuff: {type: Date, default: Date.now},
    damNestedAgain: [String]
  ]
})

So to recap, damNested array is inside the comments array on the schema.

If I was lucky and wanted to change normalStuff (obj inside an array), I'd do this:

mySchema.findOneAndUpdate({"comments._id": req.body.commentId},
{
    $push:
    {
      comments: { normalStuff: 12122020 } }
    }
})

This would've updated normalStuff with a new value.

However, I need to update a field in damNestedAgain , but don't know how to reach it!

Question

How to update the nested array of a nested array, damNestedAgain , in my example?

Answer 1

mySchema.findOneAndUpdate({"comments._id": req.body.commentId},
{
    $push:
    {
      "comments.$.damNestedAgain": req.body.commentId
    }
})

That has done the trick, thanks.