upsert (update or create) a nested array in mongoose near atomicly without save function

schema.js

import mongoose from 'mongoose';
import _ from 'lodash';
import dotize from 'dotize';

ApplicationSchema.methods.upsertRelease = function(query, object) {
  const application = this;

  // Create an object from query using dot notation instead of objects ('releases.github.id')
  const dotQuery = dotize.convert(query, 'releases');
  // Create an object of values to update to, uses mongoose's $ operator
  const dotUpdate = dotize.convert(object, 'releases.$');
  // Create a new object of dotQuery, but with mongodb's not operator for value
  const notDotQuery = _.mapValues(dotQuery, value => ({ $ne: value }));

  return Promise.all([ // Return two promises, one for update, and one for insert
    Application.update(_.extend({ // Find an application with same _id, and includes release query
      _id: application._id,
    }, dotQuery), dotUpdate), // Use generated dotUpdate object for updating
    Application.update(_.extend({ // Find an application that has _id but does NOT include release (avoids adding when already exists)
      _id: application._id,
    }, notDotQuery), {
      $addToSet: {
        releases: object, // Push new release into array
      },
    }),
  ]);
}

This function comes in handy when using promises that run in parallel. It does not use any .save() functions, so it will never be using out of date information to calculate existence. It depends on one of the functions failing while the other succeeds, hence the not query in the second function.