Saving to MongoDB using Mongoose fails on ObjectId as string

Question

I'm currently receiving a validation error when trying to save my object to MongoDB using Mongoose/Joigoose. The basic gist of the schema is that of a simple Group object with a reference to a parent Group's ObjectId (parent_group).

Here's the error: ValidationError: parent_group: Validator failed for path 'parent_group' with value '5f32d6c58d0c4a080c48bc79'

The code for my Group schema definition looks like this:

// Imports (for reference)
const mongoose = require('mongoose'); // v5.9.29
const Joigoose = require('joigoose')(mongoose); // v7.1.2
const Joi = require('@hapi/joi'); // v17.1.1
const uniqueValidator = require('mongoose-unique-validator'); // v2.0.3
const ObjectId = mongoose.Schema.Types.ObjectId;

// Schema
const joiGroupSchema = Joi.object().keys({
    id: Joi.string().required().meta({ _mongoose: { unique: true }}).regex(/^[\w-]+$/).max(50),
    name: Joi.string().required().max(50),
    notes: Joi.string().allow(null),
    parent_group: Joi.string().allow(null).regex(/^[0-9A-Fa-f]*$/).max(24).meta({ _mongoose: { type: ObjectId, ref: 'Group' }}),
}).options({stripUnknown: true});

const groupSchema = new mongoose.Schema(Joigoose.convert(joiGroupSchema));
groupSchema.plugin(uniqueValidator);
const Group = mongoose.model("Group", groupSchema);

My mongoose save call looks like this:

// This code is inside of an Express HTTP POST definition (hence the result.value and req/res)
let model = new Group(result.value);
model.save(function (err, doc) {
    // On error
    if (err) {
        if (err.errors.id && err.errors.id.properties.type == 'unique') {
            res.status(409);
            return res.send('POST failed');
        }
        res.status(500);
        return res.send('POST failed');
    }
    res.status(200);
    return res.send('success');
});

The data I'm passing using Postman looks like this:

{
    "id": "asdf",
    "name": "ASDF",
    "notes": "postman",
    "parent_group": "5f32d6c58d0c4a080c48bc79"
}

I've tried different formats of the parent_group string, tried passing it through JS after converting it using mongoose.Types.ObjectId("5f32d6c58d0c4a080c48bc79") , but I keep receiving the same error. I was unable to identify which validator is failing, but that could just be my unfamiliarity with debugging Mongoose.

It is also worth noting:

• the ObjectId is correct
• a null ObjectId works just fine
• the error is being caught in model.save()

Any help would be much appreciated!

Answer 1

The reason my ObjectId was failing validation is joigoose adds joi validators to the Mongoose schema behind the scenes . Without looking into it too deeply, my understanding is that when joi validates the ObjectId as a string, it passes; after Mongoose converts the ObjectId to an object rather than a string (as the joi validator was expecting), that's where the added validator fails.

Since adding joi validators to Mongoose schema is not a functionality that I want (I am just using joigoose to consolidate schemas), as a quick-and-dirty fix, I commented that section out of joigoose directly in my local copy of it. I am currently using patch-package to maintain this patch in my application.