NAME
    Data::MessagePack - MessagePack serializing/deserializing

SYNOPSIS
        use Data::MessagePack;

        my $mp = Data::MessagePack->new();
        $mp->canonical->utf8->prefer_integer if $needed;

        my $packed   = $mp->pack($dat);
        my $unpacked = $mp->unpack($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})); # => 7

        The 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 a
        blessed perl object, because MessagePack is a language-independent
        format.

    "my $unpacked = Data::MessagePack->unpack($msgpackstr);"
        unpack the $msgpackstr to a MessagePack format string.

    "my $mp = Data::MesssagePack->new()"
        Creates a new MessagePack instance.

    "$mp = $mp->prefer_integer([ $enable ])"
    "$enabled = $mp->get_prefer_integer()"
        If *$enable* is true (or missing), then the "pack" method tries a
        string as an integer if the string looks like an integer.

    "$mp = $mp->canonical([ $enable ])"
    "$enabled = $mp->get_canonical()"
        If *$enable* is true (or missing), then the "pack" method will
        output packed data by sorting their keys. This is adding a
        comparatively high overhead.

    "$mp = $mp->utf8([ $enable ])"
    "$enabled = $mp->get_utf8()"
        If *$enable* is true (or missing), then the "pack" method will apply
        "utf8::encode()" to all the string values.

        In other words, this property tell $mp to deal with text strings.
        See perlunifaq for the meaning of text string.

    "$packed = $mp->pack($data)"
    "$packed = $mp->encode($data)"
        Same as "Data::MessagePack->pack()", but properties are respected.

    "$data = $mp->unpack($data)"
    "$data = $mp->decode($data)"
        Same as "Data::MessagePack->unpack()", but properties are respected.

Configuration Variables (DEPRECATED)
    $Data::MessagePack::PreferInteger
        Packs a string as an integer, when it looks like an integer.

        This variable is deprecated. Use "$msgpack->prefer_integer" property
        instead.

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.

FAQ
    Why does Data::MessagePack have pure perl implementations?
        msgpack C library uses C99 feature, VC++6 does not support C99. So
        pure perl version is needed for VC++ users.

AUTHORS
    Tokuhiro Matsuno

    Makamaka Hannyaharamitu

    gfx

THANKS TO
    Jun Kuriyama

    Dan Kogai

    FURUHASHI Sadayuki

    hanekomu

    Kazuho Oku

    shohex

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.

    Data::MessagePack::Unpacker

    AnyEvent::MPRPC
