Delete is not working for javascript object in NodeJs

Did you try lean() when you query? like find(query).lean()... check this http://blog.sandromartis.com/2016/05/08/mongoose-lean/ This will allow you to do any operation to the object.

Other way could be extending the root object with removing unwanted properties from it. you can use https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign

example:

var obj = { a: 1 };
var copy = Object.assign({}, obj);
console.log(copy); // { a: 1 }
delete copy._id;//or whatever you want
console.lg(copy);//check this doesnt have the _id;

Thanks Hope this helps

I recently had a similar problem. I used loadash to cut off the values I didn't need from the array, but had to use .toObject() in the fetched object so I could use it as an argument. Something like:

let resultExample = _.omit(exampleObject.toObject(), ['x', 'y', 'z']);

use something like this 

 var event= event.toObject();
 delete event._id;

Old question, but I'm throwing my 2-cents into the fray....

I came across this issue and I used Object.entries() + Array.reduce() to solve it. Here's my take:

// define dis-allowed keys and values
const disAllowedKeys = ['_id','__v','password'];
const disAllowedValues = [null, undefined, ''];

// our object, maybe a Mongoose model, or some API response
const someObject = {
  _id: 132456789,
  password: '$1$O3JMY.Tw$AdLnLjQ/5jXF9.MTp3gHv/',
  name: 'John Edward',
  age: 29,
  favoriteFood: null
}; 

// use reduce to create a new object with everything EXCEPT our dis-allowed keys and values!
const withOnlyGoodValues = Object.entries(someObject).reduce((ourNewObject, pair) => {
  const key = pair[0];
  const value = pair[1]; 
  if (
    disAllowedKeys.includes(key) === false &&
    disAllowedValues.includes(value) === false
  ){
    ourNewObject[key] = value; 
  }
  return ourNewObject; 
}, {}); 

// what we get back...
// {
//   name: 'John Edward',
//   age: 29
// }

// do something with the new object!
server.sendToClient(withOnlyGoodValues);

This can be cleaned up more once you understand how it works, especially with some fancy ES6 syntax. I intentionally tried to make it extra-readable, for the sake of the demo.

Read docs on how Object.entries() works: MDN - Object.entries()

Read docs on how Array.reduce() works: MDN - Array.reduce()

Thanks for quick help. You first solution works, but has only issue that, properties are hardcoded, though we can make it configurable. Second solution I tried but couldn't gives any effect. Third one is good, but copies hell lot of properties, those we really don't required.

Apart from these I tried following solution and works for now, though its costly for performance but its fine till I don't get one proper:

let savableEvent = JSON.parse(JSON.stringify(event));
delete savableEvent._id;
delete savableEvent.__v;
delete savableEvent.__t;

Will post if I get something better.