Why can't I delete a mongoose model's object properties?

Question

When a user registers with my API they are returned a user object. Before returning the object I remove the hashed password and salt properties. I have to use

user.salt = undefined; user.pass = undefined; 

Because when I try

delete user.salt; delete user.pass; 

the object properties still exist and are returned.

Why is that?

Answer 1

To use delete you would need to convert the model document into a plain JavaScript object by calling toObject so that you can freely manipulate it:

user = user.toObject(); delete user.salt; delete user.pass; 

Answer 2

Non-configurable properties cannot be re-configured or deleted.

You should use strict mode so you get in-your-face errors instead of silent failures:

(function() {     "use strict";      var o = {};      Object.defineProperty(o, "key", {          value: "value",          configurable: false,          writable: true,          enumerable: true      });      delete o.key; })() // TypeError: Cannot delete property 'key' of #<Object>