/**
* Return the Random Access Token.
* The access method should be POST.
* The POST body should include 'client_id', 'client_secret', 'grant_type', 'code' and 'redirect_uri' used before.
* The 'grant_type' must be 'authorization_code';
* The 'client_id' and 'client_secret' are registered in developer's center.
* @return array AccessToken array if above parameters are valid, or error No. and message.
*/
public function run()
{
GrantType::checkGrantType(Yii::$app->request->post('grant_type'), GrantType::GRANT_TYPE_AUTHORIZATION_CODE);
Client::checkClientSecret(Client::checkClientId(Yii::$app->request->post('client_id')), Yii::$app->request->post('client_secret'));
AuthorizationCode::checkAuthorizationCode(Yii::$app->request->post('code'), Yii::$app->request->post('redirect_uri'));
return AccessToken::createAccessToken(Yii::$app->request->post('client_id'), Yii::$app->request->post('code'));
}
