distill.js

var distill = require('distill');
var data = {
  id: 1,
  title: 'Hello, World',
  dirty_field: 'This field should not be exposed.',
  authors: {
    id: 2,
    name: 'Joshua',
    email: 'joshua@example.org'
  }
};

var output =
  distill(data)
    .field('id')
    .field('title')
    .embed('authors', 'id')
    .bottle();

// Output
{
  id: 1,
  title: 'Hello, World',
  authors: [
    { id: 2 }
  ]
}