/**
* Decompress a message
*
* @param string $msg Message
* @param integer $compression 0=none, 1=gzip, 2=snappy
*
* @return string
* @throws \Kafka\Exception
*/
public static function decompress($msg, $compression)
{
switch ($compression) {
case self::COMPRESSION_NONE:
return $msg;
case self::COMPRESSION_GZIP:
// NB: this is really a MessageSet, not just a single message
// although I'm not sure this is the best way to handle the inner offsets,
// as the symmetry with the outer collection iteration is broken.
// @see https://issues.apache.org/jira/browse/KAFKA-406
$stream = fopen('php://temp', 'w+b');
fwrite($stream, gzinflate(substr($msg, 10)));
rewind($stream);
$socket = Socket::createFromStream($stream);
return new MessageSetInternalIterator($socket, 0, 0);
case self::COMPRESSION_SNAPPY:
throw new Exception\NotSupported('SNAPPY decompression not yet implemented');
default:
throw new Exception\NotSupported('Unknown compression flag: ' . $compression);
}
}
