Provided by: libmoosex-storage-perl_0.45-1_all 
NAME
MooseX::Storage - A serialization framework for Moose classes
VERSION
version 0.45
SYNOPSIS
package Point;
use Moose;
use MooseX::Storage;
with Storage('format' => 'JSON', 'io' => 'File');
has 'x' => (is => 'rw', isa => 'Int');
has 'y' => (is => 'rw', isa => 'Int');
1;
my $p = Point->new(x => 10, y => 10);
## methods to pack/unpack an
## object in perl data structures
# pack the class into a hash
$p->pack(); # { __CLASS__ => 'Point-0.01', x => 10, y => 10 }
# unpack the hash into a class
my $p2 = Point->unpack({ __CLASS__ => 'Point-0.01', x => 10, y => 10 });
## methods to freeze/thaw into
## a specified serialization format
## (in this case JSON)
# pack the class into a JSON string
$p->freeze(); # { "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }
# unpack the JSON string into a class
my $p2 = Point->thaw('{ "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }');
## methods to load/store a class
## on the file system
$p->store('my_point.json');
my $p2 = Point->load('my_point.json');
DESCRIPTION
MooseX::Storage is a serialization framework for Moose, it provides a very flexible and
highly pluggable way to serialize Moose classes to a number of different formats and
styles.
Important Note
This is still an early release of this module, so use with caution. It's outward facing
serialization API should be considered stable, but I still reserve the right to make
tweaks if I need too. Anything beyond the basic pack/unpack, freeze/thaw and load/store
should not be relied on.
Levels of Serialization
There are 3 levels to the serialization, each of which builds upon the other and each of
which can be customized to the specific needs of your class.
base
The first (base) level is "pack" and "unpack". In this level the class is serialized
into a Perl HASH reference, it is tagged with the class name and each instance
attribute is stored. Very simple.
This level is not optional, it is the bare minimum that MooseX::Storage provides and
all other levels build on top of this.
See MooseX::Storage::Basic for the fundamental implementation and options to "pack"
and "unpack"
format
The second (format) level is "freeze" and "thaw". In this level the output of "pack"
is sent to "freeze" or the output of "thaw" is sent to "unpack". This levels primary
role is to convert to and from the specific serialization format and Perl land.
This level is optional, if you don't want/need it, you don't have to have it. You can
just use "pack"/"unpack" instead.
io The third (io) level is "load" and "store". In this level we are reading and writing
data to file/network/database/etc.
This level is also optional, in most cases it does require a "format" role to also be
used, the exception being the "StorableFile" role.
Behaviour modifiers
The serialization behaviour can be changed by supplying "traits". This can be done as
follows:
use MooseX::Storage;
with Storage( traits => [Trait1, Trait2,...] );
The following traits are currently bundled with "MooseX::Storage":
OnlyWhenBuilt
Only attributes that have been built (i.e., where the predicate returns 'true') will
be serialized. This avoids any potentially expensive computations.
See MooseX::Storage::Traits::OnlyWhenBuilt for details.
How we serialize
There are always limits to any serialization framework, there are just some things which
are really difficult to serialize properly and some things which cannot be serialized at
all.
What can be serialized?
Currently only numbers, string, ARRAY refs, HASH refs and other MooseX::Storage enabled
objects are supported.
With Array and Hash references the first level down is inspected and any objects found are
serialized/deserialized for you. We do not do this recursively by default, however this
feature may become an option eventually.
The specific serialize/deserialize routine is determined by the Moose type constraint a
specific attribute has. In most cases subtypes of the supported types are handled
correctly, and there is a facility for adding handlers for custom types as well. This will
get documented eventually, but it is currently still in development.
What can not be serialized?
We do not support CODE references yet, but this support might be added in using B::Deparse
or some other deep magic.
Scalar refs are not supported, mostly because there is no way to know if the value being
referenced will be there when the object is inflated. I highly doubt will be ever support
this in a general sense, but it would be possible to add this yourself for a small
specific case.
Circular references are specifically disallowed, however if you break the cycles yourself
then re-assemble them later you can get around this. The reason we disallow circular refs
is because they are not always supported in all formats we use, and they tend to be very
tricky to do for all possible cases. It is almost always something you want to have tight
control over anyway.
CAVEAT
This is not a persistence framework; changes to your object after you load or store it
will not be reflected in the stored class.
EXPORTS
Storage (%options)
This module will export the "Storage" method and can be used to load a specific set of
MooseX::Storage roles to implement a specific combination of features. It is meant to
make things easier, but it is by no means the only way. You can still compose your
roles by hand if you like.
By default, options are assumed to be short forms. For example, this:
Storage(format => 'JSON');
...will result in looking for MooseX::Storage::Format::JSON. To use a role that is
not under the default namespace prefix, start with an equal sign:
Storage(format => '=My::Private::JSONFormat');
To use a parameterized role (for which, see MooseX::Role::Parameterized) you can pass
an arrayref of the role name (in short or long form, as above) and its parameters:
Storage(format => [ JSONpm => { json_opts => { pretty => 1 } } ]);
METHODS
import
Introspection
meta
TODO
This module needs docs and probably a Cookbook of some kind as well. This is an early
release, so that is my excuse for now :)
For the time being, please read the tests and feel free to email me if you have any
questions. This module can also be discussed on IRC in the #moose channel on irc.perl.org.
BUGS
All complex software has bugs lurking in it, and this module is no exception. If you find
a bug please either email me, or add the bug to cpan-RT.
AUTHORS
• Chris Prather <chris.prather@iinteractive.com>
• Stevan Little <stevan.little@iinteractive.com>
• XXXX XXX'XX (Yuval Kogman) <nothingmuch@woobling.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2007 by Infinity Interactive, Inc..
This is free software; you can redistribute it and/or modify it under the same terms as
the Perl 5 programming language system itself.
CONTRIBUTORS
• Chris Prather <chris@prather.org>
• Cory Watson <gphat@Crankwizzah.local>
• Dagfinn Ilmari Mannsaaker <ilmari@ilmari.org>
• David Golden <dagolden@cpan.org>
• David Steinbrunner <dsteinbrunner@pobox.com>
• Florian Ragwitz <rafl@debian.org>
• Johannes Plunien <plu@pqpq.de>
• Jonathan Rockway <jon@jrock.us>
• Jonathan Yu <frequency@cpan.org>
• Jos Boumans <jos@dwim.org>
• Karen Etheridge <ether@cpan.org>
• Ricardo Signes <rjbs@cpan.org>
• Robert Boone <robo4288@gmail.com>
• Shawn M Moore <sartak@gmail.com>
• Tomas Doran <bobtfish@bobtfish.net>
• Yuval Kogman <nothingmuch@woobling.org>