overleaf/services/web/scripts/add_multiple_emails.js

const mongojs = require('../app/js/infrastructure/mongojs')
const { db } = mongojs
const async = require('async')
const minilist = require('minimist')

const updateUser = function (user, callback) {
  console.log(`Updating user ${user._id}`)
  const update = {
    $set: {
      emails: [{
        email: user.email,
        createdAt: new Date()
      }]
    }
  }
  db.users.update({_id: user._id}, update, callback)
}

const updateUsers = (users, callback) =>
  async.eachLimit(users, ASYNC_LIMIT, updateUser, function (error) {
    if (error) {
      callback(error)
      return
    }
    counter += users.length
    console.log(`${counter} users updated`)
    loopForUsers(callback)
  })

var loopForUsers = callback =>
  db.users.find(
    { emails: {$exists: false} },
    { email: 1 }
  ).limit(FETCH_LIMIT, function (error, users) {
    if (error) {
      callback(error)
      return
    }
    if (users.length === 0) {
      console.log(`DONE (${counter} users updated)`)
      return callback()
    }
    updateUsers(users, callback)
  })

var counter = 0
var run = () =>
  loopForUsers(function (error) {
    if (error) { throw error }
    process.exit()
  })

let FETCH_LIMIT, ASYNC_LIMIT
var setup = function () {
  let args = minilist(process.argv.slice(2))
  FETCH_LIMIT = (args.fetch) ? args.fetch : 100
  ASYNC_LIMIT = (args.async) ? args.async : 10
}

setup()
run()