Seed DB with Mongoose

seeds.js

require('./database');
var Celebrity = require('../models/celebrity');
var Movie = require('../models/movie');

Promise.all([Celebrity.remove({}), Movie.remove({})])

.then(function() {
  return Celebrity.create([
    {name: 'Don Johnson'},
    {name: 'Harrison Ford'},
    {name: 'Chewy'},
    {name: 'Val Kilmer'}
  ]);
})

.then(function(celebs) {
  console.log('celebs created:\n', celebs);
  return Movie.create([
    {title: 'Star Wars', celebrities: [celebs[2]._id, celebs[1]._id]},
    {title: 'Top Gun', celebrities: [celebs[3]._id]},
    {title: 'Miami Vice - The Movie', celebrities: [celebs[0]._id]},
    {title: 'Scarface'}
  ]);
})

.then(function(movies) {
  // log out movies before populating celebrities
  console.log('movies without populated celebrities:\n', movies);
  // demo population of celebities
  return Movie.find({}).populate('celebrities').exec();
})

.then(function(movies) {
  // third arg in stringify specifies whitespace for pretty print
  console.log('movies with populated celebrities:\n', JSON.stringify(movies, null, 2));
  // remove Harrison Ford
  return Celebrity.findOne({name: 'Harrison Ford'});
})

.then(function(harrison) {
  return harrison.remove();
})

.then(function() {
  // check if Harrison is removed
  return Celebrity.find({});
})

.then(function(celebrities) {
  // verify no more Harrison
  console.log('verify no more Harrison:\n', celebrities);
  // now gonna check post remove middleware on Celebrity model
  return Movie.find({});
})

.then(function(movies) {
  // verify Harrison removed from Star Wars
  console.log('verify Harrison removed from Star Wars:\n', JSON.stringify(movies, null, 2));
})

.then(function() {
  require('mongoose').connection.close();
  process.exit();
});