BoxGetAllUsers.js

'use strict';
const box = require('box-node-sdk');
const fs = require('fs');
const util = require('util');

let configFile = fs.readFileSync('config.json');
configFile = JSON.parse(configFile);

let session = box.getPreconfiguredInstance(configFile);
let serviceAccountClient = session.getAppAuthClient("enterprise");
serviceAccountClient._useIterators = true;

serviceAccountClient.enterprise.getUsers({ limit: 1000 })
    .then((usersIterator) => {
        return autoPage(usersIterator);
    })
    .then((usersCollection) => {
        console.log(usersCollection.length);
    });

function autoPage(iterator) {
    let collection = [];
    let moveToNextItem = () => {
        return iterator.next()
            .then((item) => {
                if (item.value) {
                    collection.push(item.value);
                }
                if (item.done !== true) {
                    return moveToNextItem();
                } else {
                    return collection;
                }
            })
    }
    return moveToNextItem();
}