2 package MooseX::Storage;
5 use MooseX::Storage::Meta::Attribute::DoNotSerialize;
12 return if $pkg eq 'main';
15 || confess "This package can only be used in Moose based classes";
17 $pkg->meta->alias_method('Storage' => sub {
20 $params{'base'} ||= 'Basic';
23 ('MooseX::Storage::' . $params{'base'}),
27 # you don't have to have a format
28 # role, this just means you dont
29 # get anything other than pack/unpack
30 push @roles => 'MooseX::Storage::Format::' . $params{'format'}
31 if exists $params{'format'};
34 # if you do choose an IO role, then
35 # you *must* have a format role chosen
36 # since load/store require freeze/thaw
37 if (exists $params{'io'}) {
38 (exists $params{'format'})
39 || confess "You must specify a format role in order to use an IO role";
40 push @roles => 'MooseX::Storage::IO::' . $params{'io'};
43 Class::MOP::load_class($_)
44 || die "Could not load role (" . $_ . ") for package ($pkg)"
59 MooseX::Storage - An serialization framework for Moose classes
67 our $VERSION = '0.01';
69 with Storage('format' => 'JSON', 'io' => 'File');
71 has 'x' => (is => 'rw', isa => 'Int');
72 has 'y' => (is => 'rw', isa => 'Int');
76 my $p = Point->new(x => 10, y => 10);
78 ## methods to pack/unpack an
79 ## object in perl data structures
81 # pack the class into a hash
82 $p->pack(); # { __CLASS__ => 'Point-0.01', x => 10, y => 10 }
84 # unpack the hash into a class
85 my $p2 = Point->unpack({ __CLASS__ => 'Point-0.01', x => 10, y => 10 });
87 ## methods to freeze/thaw into
88 ## a specified serialization format
89 ## (in this case JSON)
91 # pack the class into a JSON string
92 $p->freeze(); # { "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }
94 # unpack the JSON string into a class
95 my $p2 = Point->thaw('{ "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }');
97 ## methods to load/store a class
100 $p->store('my_point.json');
102 my $p2 = Point->load('my_point.json');
106 MooseX::Storage is a serialization framework for Moose, it provides
107 a very flexible and highly pluggable way to serialize Moose classes
108 to a number of different formats and styles.
110 =head2 Important Note
112 This is still an early release of this module, so use with caution.
113 It's outward facing serialization API should be considered stable,
114 but I still reserve the right to make tweaks if I need too. Anything
115 beyond the basic pack/unpack, freeze/thaw and load/store should not
118 =head2 Levels of Serialization
120 There are 3 levels to the serialization, each of which builds upon
121 the other and each of which can be customized to the specific needs
128 The first (base) level is C<pack> and C<unpack>. In this level the
129 class is serialized into a Perl HASH reference, it is tagged with the
130 class name and each instance attribute is stored. Very simple.
132 This level is not optional, it is the bare minumum that
133 MooseX::Storage provides and all other levels build on top of this.
137 The second (format) level is C<freeze> and C<thaw>. In this level the
138 output of C<pack> is sent to C<freeze> or the output of C<thaw> is sent
139 to C<unpack>. This levels primary role is to convert to and from the
140 specific serialization format and Perl land.
142 This level is optional, if you don't want/need it, you don't have to
143 have it. You can just use C<pack>/C<unpack> instead.
147 The third (io) level is C<load> and C<store>. In this level we are reading
148 and writing data to file/network/database/etc.
150 This level is also optional, it does however require the C<format> level
151 to be present (at least the current state does).
155 =head2 How we serialize
157 There are always limits to any serialization framework, there are just
158 some things which are really difficult to serialize properly and some
159 things which cannot be serialized at all.
161 =head2 What can be serialized?
163 Currently only numbers, string, ARRAY refs, HASH refs and other
164 MooseX::Storage enabled objects are supported.
166 With Array and Hash references the first level down is inspected and
167 any objects found are serialized/deserialized for you. We do not do
168 this recusively by default, however this feature may become an
171 The specific serialize/deserialize routine is determined by the
172 Moose type constraint a specific attribute has. In most cases subtypes
173 of the supported types are handled correctly, and there is a facility
174 for adding handlers for custom types as well. This will get documented
175 eventually, but it is currently still in development.
177 =head2 What can not be serialized?
179 We do not support CODE references yet, but this support might be added
180 in using B::Deparse or some other deep magic.
182 Scalar refs are not supported, mostly because there is no way to know
183 if the value being referenced will be there when the object is inflated.
184 I highly doubt will be ever support this in a general sense, but it
185 would be possible to add this yourself for a small specific case.
187 Circular references are specifically disallowed, however if you break
188 the cycles yourself then re-assemble them later you can get around this.
189 The reason we disallow circular refs is because they are not always supported
190 in all formats we use, and they tend to be very tricky to do for all
191 possible cases. It is almost always something you want to have tight control
196 This is B<not> a persistence framework, changes to your object after
197 you load or store it will not be reflected in the stored class.
203 =item B<Storage (%options)>
205 This module will export the C<Storage> method will can be used to
206 load a specific set of MooseX::Storage roles to implement a specific
207 combination of features. It is meant to make things easier, but it
208 is by no means the only way. You can still compose your roles by
231 This module needs docs and probably a Cookbook of some kind as well.
232 This is an early release, so that is my excuse for now :)
234 For the time being, please read the tests and feel free to email me
235 if you have any questions. This module can also be discussed on IRC
236 in the #moose channel on irc.perl.org.
240 All complex software has bugs lurking in it, and this module is no
241 exception. If you find a bug please either email me, or add the bug
246 Chris Prather E<lt>chris.prather@iinteractive.comE<gt>
248 Stevan Little E<lt>stevan.little@iinteractive.comE<gt>
250 =head1 COPYRIGHT AND LICENSE
252 Copyright 2007 by Infinity Interactive, Inc.
254 L<http://www.iinteractive.com>
256 This library is free software; you can redistribute it and/or modify
257 it under the same terms as Perl itself.