gistfile1.txt

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

let configFile = fs.readFileSync('config.json');
configFile = JSON.parse(configFile);
let session = box.getPreconfiguredInstance(configFile);
let serviceAccountClient = session.getAppAuthClient('user');

serviceAccountClient.enterprise.addAppUser("Jonathan", { "external_app_user_id": "jonathan" })
  .then((user) => {
    console.log(user);
  })
  .catch((err) => {
    handleConflictError(err);
  });

const handleConflictError = (err) => {
    let userID;
    if (err && err.response && err.response.body && err.response.body.context_info &&
        err.response.body.context_info && err.response.body.context_info.conflicts) {
        if (err.response.body.context_info.conflicts.length > 0) {
            console.log(err.response.body.context_info);
            userID = err.response.body.context_info.conflicts[0].id;
            console.log("User already exists");
            console.log(userID);
        }
    }
}