Recursive updating of Mongoose document - node.js

Question

I am currently trying to implement symmetrical (AES256-GCM) encryption to a document before it gets saved into the database. Therefore I have hooked into the pre('save') method to grab data and encrypt it before it gets saved to the database. I need to do this to meet regulations which require all medical data to be encrypted and can only be decrypted by the user who owns the data. This is was for a bit of background
So I have a complex schema setup for the user which contains a lot of PII information so I can't post an example but I can give you a sanitised JSON structure of the data, that doesn't give away what I am working on. (NDAs...).
{
"title": "",
"firstName": "",
"lastName": "",
"XXXXXXXXXX": [{
"XXX": "",
"XXX": "",
"XXX": "",
"XXX": "",
"XXX": "",
"XXX": "",
"XXX": "",
"XXX": ""
}],
"contact": {
"contactNumbers": [{
"type": "",
"number": ""
}],
"emailAddresses": [{
"type": "",
"address": ""
}]
},
"XXX": {
"XXX": {
"XXX": "",
"firstName": "",
"lastName": "",
"XXX": ""
},
"XXX": [{
"XXX": "",
"firstName": "",
"lastName": "",
"XXX": ""
}],
"name": "",
"XXX": "",
"XXX": "",
"XXX": ""
},
"XXX": [{
"name": "",
"number": ""
}],
"XXX": [{
"code": "",
"name": "",
"XXX": "",
"XXX": ""
}],
"XXX": [{
"code": "",
"name": "",
"XXX": "",
"XXX": ""
}],
"XXX": [{
"name": "",
"XXX": "",
"contactNumber": "",
"emailAddress": "",
"address": {
"street1": "",
"street2": "",
"suburb": "",
"city": "",
"province": "",
"country": "",
"postalCode": ""
}
}]
}
So I have been trying to recursively loop through the data so that I can encrypt each field before saving the document. I came across the following package which somewhat works. It doesn't recurse into the arrays. I tried converting the document into a JSON Object to make it easier to work with. Which didn't help much besides removing the metadata from the document object.
I was trying to write a cursive function (C# is my wheelhouse) but I cannot access the length of the children of a JSON object so I couldn't recurse on that.
I would greatly appreciate it if someone has a solution to recursing through a Mongoose document, because I am stumped.

Answer 1

Okay, so that package I mentioned did the trick. There is an unspecified option that treats arrays as objects which allows the iterator to recurse into the arrays. So the working iterator looks as follows:
let iterator = require('object-recursive-iterator');
iterator.forAll(jsonProfile, (path, key, obj) => {
obj[key] = 'processed';
}, {treatArrayAsObject: true});
Hope this helps someone in the future.