When using findOneAndUpdate(), how to leave fields as is if no value provided (instead of overwriting with null)?

Question

The user has the option of updating any of a few values - however, if he only passes in { name: "new name" }, the email and password fields are also updated but to "null".

How can I only update the fields that are actually provided in req.body, leaving the rest as they are?

This is while still specifying which fields can be updated with a POST request - I've avoided just passing in req.body because I'd like to limit this.

My code looks like:

db.User.findOneAndUpdate({_id: req.params.id}, { 
        name: req.body.name,
        email: req.body.emaill, 
        password: req.body.password
})

Using something like name: req.body.name && req.body.name to check if a value is not undefined also overwrites with "null".

Thanks!

Answer 1

Prepare your update object first:

let params = { 
        name: req.body.name,
        email: req.body.emaill, 
        password: req.body.password
};

for(let prop in params) if(!params[prop]) delete params[prop]; //This will not handle intentionally setting to false, empty string, null, 0, or other falsey values.

db.User.findOneAndUpdate({_id: req.params.id}, params);

Or, if your property names match:

let params = {};

for(let prop in req.body) if(req.body[prop]) params[prop] = req.body[prop];

db.User.findOneAndUpdate({_id: req.params.id}, params);