function getEndpoint()
    {
        $this->api->curl_header = array(
            'Authorization: OAuth '.$this->api->access_token,
        );
        $data = $this->api->get( $this->metadata_url );

        if ( ! isset( $data->api_endpoint ) ){
            throw new Exception( "Endpoint request failed! {$this->providerId} returned an invalid response.", 6 );
        }

        return $data->api_endpoint;
    }