NAME
Data::MessagePack - MessagePack serialising/deserialising
SYNOPSIS
use Data::MessagePack;
my $packed = Data::MessagePack->pack($dat);
my $unpacked = Data::MessagePack->unpack($dat);DESCRIPTION
This module converts Perl data structures to MessagePack and vice versa.
ABOUT MESSAGEPACK FORMAT
MessagePack is a binary-based efficient object serialization format. It enables to exchange structured objects between many languages like JSON. But unlike JSON, it is very fast and small.
ADVANTAGES
- PORTABLE
-
The MessagePack format does not depend on language nor byte order.
- SMALL IN SIZE
-
say length(JSON::XS::encode_json({a=>1, b=>2})); # => 13 say length(Storable::nfreeze({a=>1, b=>2})); # => 21 say length(Data::MessagePack->pack({a=>1, b=>2})); # => 7The MessagePack format saves memory than JSON and Storable format.
- STREAMING DESERIALIZER
-
MessagePack supports streaming deserializer. It is useful for networking such as RPC. See Data::MessagePack::Unpacker for details.
If you want to get more information about the MessagePack format, please visit to http://msgpack.org/.
METHODS
- my $packed = Data::MessagePack->pack($data[, $max_depth]);
-
Pack the $data to messagepack format string.
This method throws an exception when the perl structure is nested more than $max_depth levels(default: 512) in order to detect circular references.
Data::MessagePack->pack() throws an exception when encountering blessed object, because MessagePack is language-independent format.
- my $unpacked = Data::MessagePack->unpack($msgpackstr);
-
unpack the $msgpackstr to a MessagePack format string.
Configuration Variables
SPEED
This is a result of benchmark/serialize.pl and benchmark/deserialize.pl on my SC440(Linux 2.6.32-23-server #37-Ubuntu SMP). (You should benchmark them with your data if the speed matters, of course.)
-- serialize
JSON::XS: 2.3
Data::MessagePack: 0.24
Storable: 2.21
Benchmark: running json, mp, storable for at least 1 CPU seconds...
json: 1 wallclock secs ( 1.00 usr + 0.01 sys = 1.01 CPU) @ 141939.60/s (n=143359)
mp: 1 wallclock secs ( 1.06 usr + 0.00 sys = 1.06 CPU) @ 355500.94/s (n=376831)
storable: 1 wallclock secs ( 1.12 usr + 0.00 sys = 1.12 CPU) @ 38399.11/s (n=43007)
Rate storable json mp
storable 38399/s -- -73% -89%
json 141940/s 270% -- -60%
mp 355501/s 826% 150% --
-- deserialize
JSON::XS: 2.3
Data::MessagePack: 0.24
Storable: 2.21
Benchmark: running json, mp, storable for at least 1 CPU seconds...
json: 0 wallclock secs ( 1.05 usr + 0.00 sys = 1.05 CPU) @ 179442.86/s (n=188415)
mp: 0 wallclock secs ( 1.01 usr + 0.00 sys = 1.01 CPU) @ 212909.90/s (n=215039)
storable: 2 wallclock secs ( 1.14 usr + 0.00 sys = 1.14 CPU) @ 114974.56/s (n=131071)
Rate storable json mp
storable 114975/s -- -36% -46%
json 179443/s 56% -- -16%
mp 212910/s 85% 19% --CAVEAT
Unpacking 64 bit integers
This module can unpack 64 bit integers even if your perl does not support them (i.e. where perl -V:ivsize is 4), but you cannot calculate these values unless you use Math::BigInt.
TODO
- Error handling
-
MessagePack cannot deal with complex scalars such as object references, filehandles, and code references. We should report the errors more kindly.
- Streaming deserializer
-
The current implementation of the streaming deserializer does not have internal buffers while some other bindings (such as Ruby binding) does. This limitation will astonish those who try to unpack byte streams with an arbitrary buffer size (e.g.
while(read($socket, $buffer, $arbitrary_buffer_size)) { ... }). We should implement the internal buffer for the unpacker. - UTF8 mode
-
Data::MessagePack::Unpacker supports utf8 mode, which decodes strings as UTF8-8. << Data::MessagePack->unpack >> should support utf8 mode in a future.
AUTHORS
Tokuhiro Matsuno
Makamaka Hannyaharamitu
gfx
THANKS TO
Jun Kuriyama
Dan Kogai
FURUHASHI Sadayuki
hanekomu
LICENSE
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
http://msgpack.org/ is the official web site for the MessagePack format.