let basicAuth = btoa(`${pm.environment.get('authUsername')}:${pm.environment.get('authPassword')}`)

let echoPostRequest = {
  url: pm.environment.get('authApi'),
  method: 'POST',
  header: {
     'Content-Type': 'application/x-www-form-urlencoded',
     'Authorization': `Basic ${basicAuth}`,
  },
  body: {
      mode: 'urlencoded',
      urlencoded: [
        {key: "grant_type", value: "client_credentials", disabled: false},
        {key: "scope", value: pm.environment.get('authScopes'), disabled: false},
    ]
  }
};

var getToken = false;

if (!pm.environment.get('tokenExpiry') || !pm.environment.get('token')) {
    getToken = true;
} else if (pm.environment.get('tokenExpiry') <= (new Date()).getTime()) {
    getToken = true;
}

if (getToken === true) {
    pm.sendRequest(echoPostRequest, function (err, res) {
    console.log(err ? err : res.json());
        if (err === null) {
            var responseJson = res.json();
            pm.environment.set('token', responseJson.access_token)

            var expiryDate = new Date();
            expiryDate.setSeconds(expiryDate.getSeconds() + responseJson.expires_in);
            pm.environment.set('tokenExpiry', expiryDate.getTime());
        }
    });
}