Update boolean value inside of nested array Mongoose

Question

I have a Schema that holds an array of objects for comments and I would like to update the boolean value of the flagged comments accordingly, I have tried updateOne and aggregate but it isn't working out at this point, I have also tried to use $elemMatch but it isn't working.

The comment _id is being pulled from the front end element that has an ID that is the same as the id that needs to be pulled from MongoDB.

Comments Array within the question Schema:

    comments: [
        {
            user: {
                type: Object,
            },
            commentDate: {
                type: Date,
                default: Date.now()
            }, 
            flagged: {
                type: Boolean,
                default: false
            },
            flaggedDate:{type: Date},
            comment: String,
        }
    ],

function I tried to run last.

    const id = req.params.id

    const updateFlag = Question.updateOne(
        {
            comments: [
                {
                    _id: id
                }
            ]
        },
        {
            $set: {
                comments: [
                    {
                        flagged: req.body.flagged
                    }
                ]
            }
        }
    )

Any help would be appreciated!

Answer 1

You can do it with positional operator - $:

db.collection.update({
  "comments._id": "3"
},
{
  "$set": {
    "comments.$.flagged": true
  }
})

Working example