Nested document referencing in mongodb with mongoose - node.js

Question

I am trying to build a kanban as a project for my portfolio with the mern stack with a rest api. I am having issues querying the models with deeply nested objects in it. My idea is to have the lists be referenced in the project, the task be referenced in the list and the user be referenced in the task and the project as a contributor. My issue is getting the information of the task (title, etc.) through populating the project model with mongoose, or MongoDB for that matter. How should I approach this? Is it even possible to do with MongoDB? I see a lot of people doing this with a sql database. The four model schemas are as follows:
const projectSchema = new Schema({
title: { type: String, required: true, max: 32, trim: true },
lists: [{ type: Schema.Types.ObjectId, ref: 'List' }],
contributors: [{ type: Schema.Types.ObjectId, ref: 'User' }],
});
const listSchema = new Schema({
title: { type: String, required: true, max: 32, trim: true },
tasks: [{ type: Schema.Types.ObjectId, ref: 'Task' }],
});
const taskSchema = new Schema({
title: { type: String, required: true, max: 38, trim: true },
text: { type: String, max: 255, trim: true },
assignee: { type: Schema.Types.ObjectId, ref: 'User' },
});
const userSchema = new Schema(
Name: { type: String, required: true, trim: true },
projects: [{ type: Schema.Types.ObjectId, ref: 'Project' }],
tasks: [{ type: Schema.Types.ObjectId, ref: 'Task' }],
);
The issue I have is displaying the tasks in the list. When I populate the list with the project call, I get the ObjectId of the task, but would like to get the task title, which as it seems is not possible by applying the .populate call again. I have the following api controller/route:
router.get('/:projectId', async (req, res) => {
try {
const project = await Project.findOne({
_id: req.params.projectId,
}).populate('lists', 'title tasks');
res.json(project);
} catch (error) {
if (error) {
console.error(error.message);
res.status(500).send('Server Error');
}
}
});
How would I approach getting the task title and later on the user name for all the tasks in the list referencing a project?

Answer 1

So I found a solution to this. Not sure if this is the most efficient method to solve this. If anyone can provide a better solution, please post it on here.
I found the mongoose documents explains quite well how to populate over multiple levels.
https://mongoosejs.com/docs/populate.html#deep-populate
Now the solution for the answer looks as follows
router.get('/:projectId', async (req, res) => {
try {
const project = await Project.findOne({
_id: req.params.projectId,
}).populate({ path: 'lists', populate: { path: 'tasks' } });
res.json(project);
} catch (error) {
if (error) {
console.error(error.message);
res.status(500).send('Server Error');
}
}
});