private function getLocalWsdlPath($wsdl)
    {
        $resourcesWsdlsPath = sprintf(
            self::$RESOURCES_WSDLS_PATH_FORMAT,
            __DIR__,
            DIRECTORY_SEPARATOR
        );
        // parse_url() returns the path part of any URLs, which may be composed of
        // many sub-paths delimited by forward slashes. We replace them with
        // DIRECTORY_SEPARATOR (which works with any OSs) here to get paths to local
        // WSDLs.
        $wsdlFilePath = str_replace(
            '/',
            DIRECTORY_SEPARATOR,
            parse_url($wsdl, PHP_URL_PATH)
        );

        return $resourcesWsdlsPath . $wsdlFilePath . self::$WSDL_FILE_EXTENSION;
    }