Automate login and re-login to refresh token

collectionPreRequestScript.js

var moment = require('moment');

var tokenExpirationDate = pm.collectionVariables.get("token-expiration-date");
var currentTime = moment().format();

if ( (tokenExpirationDate === "") || (currentTime >= tokenExpirationDate) ){

    pm.sendRequest({
        url: pm.collectionVariables.get("local-url") + '/login',
        method: 'POST',
        header: {
            'content-type': 'application/json',
        },
        body: {
            mode: 'raw',
            raw: JSON.stringify({ email: pm.collectionVariables.get("admin-email"), password: pm.collectionVariables.get("admin-password") })
        }
    }, function (err, res) {

        if (res.code == 200) {
            pm.collectionVariables.set("token-expiration-date", moment().add(pm.collectionVariables.get("token-timeout"), 'm').format());
            pm.collectionVariables.set("user-token", res.json().Token);
        }

    });

}