How can i declare global variable and reuse it in each part of the script?


I have created a function in a separate file which will return an authorisation token.

At the top of the the main script I have declared a variable in the init context, i assume this is a global variable: var authToken

In the export function setup() i call the utility.generateAuthToken() function and successfully get the authtoken and the console log prints out the obtained authtoken

authToken = utility.generateAuthToken()

Part of the generateAuthToken
let loginRes =, payload_Login, header_Login)
authToken = loginRes.json(‘access_token’);
check(authToken, { ‘logged in successfully’: () => authToken !== ‘’ });

console.log(`Inside setup Authorisation token - ${authToken}`)
return authToken;

I then wish to reuse this authorisation token in the default function console.log(Inside default autorisation token - ${authToken})
However authToken is undefined: INFO[0010] Inside default autorisation token - undefined source=console

Since I have declared the variable in the init section should i not be able to use this from within all functions in the script?

The only way i have found to get the value of authToken is to define var authToken directly above export default function () and call the utility.generateAuthToken function within export default function
However this means that i call utility.generateAuthToken() each time i send a request and i only want to call this 1 time during the execution of the script store the value of autToken and reuse it.

How can i declare global variable and reuse it in each part of the script?
Or is there a better way to get and reuse authorisation tokens.

Hi @pbains1 !

Instead of using global variables, you can use the data that returns from the setup()

For instance:

import http from 'k6/http';
import { check } from "k6";

export function setup() {
  const res = http.get('');

  check(res, { 'logged in successfully': () => res.url !== '' });

  return { authToken: res.url };

export default function (data) {

Let me know if that helps,

1 Like

Hi Oleg,

Yes that helps! Thanks

1 Like

I ran into this issue as well. I wish to use the global variable in the init function as I have a test executor constant-arrival-rate which spikes at the start of my test but goes down shortly after the test is running.

For long running test my token expires and I konw that each VU has its own JS vm and currently the variable cannot be updated across the VUs when this happens, but I would like to be able to update the setup variable so I don’t have to keep running code where I have to check if the intial token is stale after it expires then check my VU init variable for expiration once I set it.

this is just pseudo code I quickly wrote out of the logic I’m thinking I will have to use

let vuToken = null;

export function setup() {
     return authenticateUsingOkta( **whatever**);

export default function(data) {
               if(    *** check if data token is NOT  expired )  {
                             ///   use  dataToken
               else {
                         if (  ** check if vuToken is null or expired ) {  
                                         vuToken  =   authenticateUsingOkta( **whatever**);
                        ///  use  vuToken