/**
* Attempts to retrieve a Request Token from an OAuth Provider which is
* later exchanged for an authorized Access Token used to access the
* protected resources exposed by a web service API.
*
* @param null|array $customServiceParameters Non-OAuth Provider-specified parameters
* @param null|string $httpMethod
* @param null|Zend_Oauth_Http_RequestToken $request
* @return Zend_Oauth_Token_Request
*/
public function getRequestToken(array $customServiceParameters = null, $httpMethod = null, Zend_Oauth_Http_RequestToken $request = null)
{
if ($request === null) {
$request = new Zend_Oauth_Http_RequestToken($this, $customServiceParameters);
} elseif ($customServiceParameters !== null) {
$request->setParameters($customServiceParameters);
}
if ($httpMethod !== null) {
$request->setMethod($httpMethod);
} else {
$request->setMethod($this->getRequestMethod());
}
$this->_requestToken = $request->execute();
return $this->_requestToken;
}