How to pass a unique value for each VU? (refresh token testing)

Grafana k6
1

Hello,
I need to test the refresh token handler with ramping arrival rate.
There is a certain array of tokens = [token1, token2…]
And I want tokens[0] to be given to VU 1, and token[1] to be given to VU 2.
And then there is a recursive update of tokens in each iterations, something like this:

const refreshTokens = JSON.parse(open('../../tests/refreshs.json'));

export async function getOnlyRefresh() {

    for (let refresh of refreshTokens) {
        let newRefresh = await oauthTokenRefresh(refresh, clientId)
        await refreshRecursive(newRefresh) //call refresh again till the end of test
    }
}

Because the way it works right now is that I give an array of tokens and each VU tries to update it

2 
const refreshTokens = JSON.parse(open('../../tests/refreshs.json'));
// refreshTokens.length = 100

assuming you execute with k6 run test.js -u 100 -d 10s

export async function getOnlyRefresh() {

    let newRefresh = await oauthTokenRefresh(refreshTokens[exec.vu.idInTest], clientId)
    await refreshRecursive(newRefresh) //call refresh again till the end of test
}

make it safe
good luck