code: function getAccessTokenSecretPair(api, callback) {
    // get authorization url
    api.getAuthorizationUrl('http://localhost/complete', function(error, url, requestToken, requestTokenSecret) {
      if (error) throw new Error('can not get authorization url, error: ' + error);
      debug(requestToken, 'got a request token');
      debug(requestTokenSecret, 'got a request token secret');
  
      // authorize application
      var i = rl.createInterface(process.stdin, process.stdout);
      i.question('Please, visit an url ' + url + ' and enter a verifier: ', function(verifier) {
        i.close();
        process.stdin.destroy();
        debug(verifier, 'entered verifier is');
  
        // get access token/secret pair
        api.getAccessToken(requestToken, requestTokenSecret, verifier, function(error, accessToken, accessTokenSecret) {
          if (error) throw new Error(error);
  
          debug(accessToken, 'got an access token');
          debug(accessTokenSecret, 'got an access token secret');
  
          callback(accessToken, accessTokenSecret);
        });
      });
    });
  }
docs: you can use your own client for OAuth routine, just identify it here and use as a second parameter for UpworkApi constructor (see the example of usage below) note: your client must support the following methods: 1. getAuthorizationUrl - gets request token/secret pair, creates and returns authorization url, based on received data 2. getAccessToken(requestToken, requestTokenSecret, verifier, callback) - requests access token/secret pair using known request token/secret pair and verifier 3. setAccessToken(token, secret, callback) - sets known access token/secret pair 4. get|post|put|delete(path, data, callback) - for GET, POST, PUT and DELETE methods respectively 5. setEntryPoint(entryPoint) - allows setup different entry point for base url  var MyClient = require('../lib/myclient').MyClient;  by default predefined lib/client.js will be used that works with other upwork oauth library a function to get access token/secret pair