Pushing items to array in mongoose - node.js

Question

i am trying to create items to specific id of collection using nodejs and mongoose but i am getting CastError which i shared below picture. So goal is, I binded items id in collection schema because collection has many items and when i create items to the specific id of collection i want to push them to items array in the collection schema.
ERROR
ITEMS ROUTE
itemRouter.post("/:collectionId", JWTAuthMiddleware, async (req, res, next) => {
const {name} = req.body
if (req.params.collectionId.length !== 24)
return next(createHttpError(400, "Invalid ID"));
const collection = await CollectionModal.findByIdAndUpdate(
req.params.collectionId,
{
$push : { items: { ...req.body, owner: req.user._id, id: uuidv4() } },
},
{ new: true }
);
if (!collection)
return next(
createHttpError(
400,
`The id ${req.params.collectionId} does not match any collections`
)
);
res.send(collection);
});
Collection schema
import mongoose from "mongoose";
const { Schema, model } = mongoose;
const collectionSchema = new Schema(
{
name: { type: String },
description: { type: String },
topic: { type: String },
image: { type: String },
additionalCustomFields: {
fieldNumber: { type: Number },
fieldName: { type: String },
fieldType: { type: String },
fieldChecked: { type: Boolean },
fieldDate: { type: Date },
},
owner: { type: Schema.Types.ObjectId, ref: "User" },
items: [{ type: Schema.Types.ObjectId, ref: "Item" }],
},
{ timestamps: true }
);
// collectionSchema.index({ "$**": "text" });
export default model("Collection", collectionSchema);
ITEM schema
import mongoose from "mongoose";
const { Schema, model } = mongoose;
const itemSchema = new Schema(
{
name: { type: String },
description: { type: String },
topic: { type: String },
image: { type: String },
comments: [
{
user: { type: Schema.Types.ObjectId, ref: "User", required: true },
text: { type: String },
},
],
tags: { type: String },
owner: { type: Schema.Types.ObjectId, ref: "User" },
likes: [{ type: Schema.Types.ObjectId, ref: "User" }],
collections: { type: Schema.Types.ObjectId, ref: "Collection" },
},
{ timestamps: true }
);
itemSchema.index({ "$**": "text" });
export default model("Item", itemSchema);

Answer 1

Are you sure that using referenced documents is the correct way to go here? Mongoose is complaining because you are trying to push whole objects to the "items" array, instead of ObjectIds of referenced documents.
You have 2 choices here:
1. use embedded documents
This way you can easily store objects directly to the items array, which does not allow you to store the Items in a seperate collection
2. first create Item documents, then push the reference to items array
In this case you have to first create the items in Item collection. Afterwards you can map the result to only ObjectIds and push these to items array of your collection document.