Kafka\Protocol\Encoder::metadataRequest PHP Method

    public function metadataRequest($topics)
    {
        if (!is_array($topics)) {
            $topics = array($topics);
        }
        foreach ($topics as $topic) {
            if (!is_string($topic)) {
                throw new \Kafka\Exception\Protocol('request metadata topic array have invalid value. ');
            }
        }
        $header = self::requestHeader('kafka-php', 0, self::METADATA_REQUEST);
        $data = self::encodeArray($topics, array(__CLASS__, 'encodeString'), self::PACK_INT16);
        $data = self::encodeString($header . $data, self::PACK_INT32);
        return $this->stream->write($data);
    }