oAuthRequest returns empty array

Question

I have created a Twitter application for a website. I would like to integrate the possibility of logging in/registering with Twitter. I am using php files as helpers, which are named TwitterOAuth.php and OAuth.php, respectively. When a user clicks on the Twitter button, he/she is redirected to a page called twitter.php, which has the following source-code:

<?php

/* Build TwitterOAuth object with client credentials. */
$connection = Common::twitter();

/* Get temporary credentials. */
$request_token = $connection->getRequestToken(App::env()->get('url'));

/* Save temporary credentials to session. */
$token = $request_token['oauth_token'];
$_SESSION['twitter'] = array('id' => $request_token['oauth_token'], 'token' => $request_token['oauth_token_secret']);

/* If last connection failed don't display authorization link. */
switch ($connection->http_code) {
  case 200:
    /* Build authorize URL and redirect user to Twitter. */
    $url = $connection->getAuthorizeURL($token);
    header('Location: ' . $url);
    break;
  default:
    /* Show notification if something went wrong. */
    var_dump($request_token);
    echo 'Could not connect to Twitter. Refresh the page or try again later.';
}

The Common::twitter() function is as follows:

/**
 * Returns the twitter OAuth service.
 * 
 * @return TwitterOAuth
 */
public static function twitter() {
    if (!self::$tw) {
        if ((User::isLoggedIn()) && (User::current()->hasTwitterAccount())) {
            self::$tw = new TwitterOAuth(
                App::env()->get('twitter', 'consumerKey'), 
                App::env()->get('twitter', 'consumerSecret'),
                App::CurrentUser()->getTwitterId(),
                App::CurrentUser()->getTwitterUserAccessToken()
            );
        } else {
            self::$tw = new TwitterOAuth(
                App::env()->get('twitter', 'consumerKey'), 
                App::env()->get('twitter', 'consumerSecret')
            );
        }
    }        

    return self::$tw;
}

In the scenario I am testing with, the else branch is executed. However, I get an exception:

Exception 'PHPErrorException' with message 'Notice [8] Undefined index: oauth_token Error on line 81 in file ...\lib\TwitterOAuth.php

The function where the problem occurs is as follows:

  /**
   * Get a request_token from Twitter
   *
   * @returns a key/value array containing oauth_token and oauth_token_secret
   */
  function getRequestToken($oauth_callback) {
    $parameters = array();
    $parameters['oauth_callback'] = $oauth_callback; 
    $request = $this->oAuthRequest($this->requestTokenURL(), 'GET', $parameters);
    $token = OAuthUtil::parse_parameters($request);
    $this->token = new OAuthConsumer($token['oauth_token'], $token['oauth_token_secret']);
    return $token;
  }

The problem is that OAuthUtil::parse_parameters($request) returns an empty array. This is happening, because $request is false, however, $this->requestTokenURL is https://api.twitter.com/oauth/request_token, $parameters has an oauth_callback, which holds the callback URL defined in the Twitter application. What could be the cause of this issue?

EDIT:

Source of `$this->oAuthRequest`:

  /**
   * Format and sign an OAuth / API request
   */
  function oAuthRequest($url, $method, $parameters) {
    if (strrpos($url, 'https://') !== 0 && strrpos($url, 'http://') !== 0) {
      $url = "{$this->host}{$url}.{$this->format}";
    }
    $request = OAuthRequest::from_consumer_and_token($this->consumer, $this->token, $method, $url, $parameters);
    $request->sign_request($this->sha1_method, $this->consumer, $this->token);
    switch ($method) {
    case 'GET':
      return $this->http($request->to_url(), 'GET');
    default:
      return $this->http($request->get_normalized_http_url(), $method, $request->to_postdata());
    }
  }

This method is inside of TwitterOAuth.php.

Answer 1

In OAuth.php there was a code chunk in the get_normalized_http_url method, namely:

$port = @$parts['port'];

This caused some errors, so I have fixed it like this:

$port = (array_key_exists('port', $parts) ? $parts['port'] : 80);

However, apparently port number 80 was the problem and after I changed the chunk to this:

$port = (array_key_exists('port', $parts) ? $parts['port'] : 443);

it worked like a spell.