Update nested array in mongodb

Question

Hello,

I have been looking for a solution to my problem, which I will mention below, but I still haven’t found the right way to solve it, the solutions I find usually update the whole array rather than some specific elements.

Problem:

const user = await Users.getById(userID); // Um documento da coleção

for (let item of items) {
    const index = user.inventory.findIndex(element => element.id == item.id);

    if (index > -1) {
        user.inventory[index].quantity += item.quantity;
    } else {
        user.inventory.push(item);
    }
}

user.markModified('inventory');
await user.save();

I want to make only one request to the database and not two as my code is currently doing, one request to get the document and another to save.

Answer 1

The mongodb javascript API provides the methods updateOne and updateMany, who accept the key $set to make partial updates.

Verify: https://docs.mongodb.com/manual/tutorial/update-documents/

If you are using Mongoose, updateOne and updateMany are registered as properties of the Model:

https://mongoosejs.com/docs/api/model.html#model_Model.updateOne

When consulting the Mongoose documentation you will usually not find the complete information, you have to consult also in the Mongo documentation.