2 package MooseX::Storage;
5 use MooseX::Storage::Meta::Attribute::DoNotSerialize;
8 our $AUTHORITY = 'cpan:STEVAN';
13 return if $pkg eq 'main';
16 || confess "This package can only be used in Moose based classes";
18 $pkg->meta->alias_method('Storage' => sub {
21 if (exists $params{'base'}) {
22 $params{'base'} = ('Base::' . $params{'base'});
25 $params{'base'} = 'Basic';
29 ('MooseX::Storage::' . $params{'base'}),
33 # you don't have to have a format
34 # role, this just means you dont
35 # get anything other than pack/unpack
36 push @roles => 'MooseX::Storage::Format::' . $params{'format'}
37 if exists $params{'format'};
40 # if you do choose an IO role, then
41 # you *must* have a format role chosen
42 # since load/store require freeze/thaw
43 if (exists $params{'io'}) {
44 (exists $params{'format'})
45 || confess "You must specify a format role in order to use an IO role";
46 push @roles => 'MooseX::Storage::IO::' . $params{'io'};
49 Class::MOP::load_class($_)
50 || die "Could not load role (" . $_ . ") for package ($pkg)"
65 MooseX::Storage - An serialization framework for Moose classes
73 our $VERSION = '0.01';
75 with Storage('format' => 'JSON', 'io' => 'File');
77 has 'x' => (is => 'rw', isa => 'Int');
78 has 'y' => (is => 'rw', isa => 'Int');
82 my $p = Point->new(x => 10, y => 10);
84 ## methods to pack/unpack an
85 ## object in perl data structures
87 # pack the class into a hash
88 $p->pack(); # { __CLASS__ => 'Point-0.01', x => 10, y => 10 }
90 # unpack the hash into a class
91 my $p2 = Point->unpack({ __CLASS__ => 'Point-0.01', x => 10, y => 10 });
93 ## methods to freeze/thaw into
94 ## a specified serialization format
95 ## (in this case JSON)
97 # pack the class into a JSON string
98 $p->freeze(); # { "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }
100 # unpack the JSON string into a class
101 my $p2 = Point->thaw('{ "__CLASS__" : "Point-0.01", "x" : 10, "y" : 10 }');
103 ## methods to load/store a class
104 ## on the file system
106 $p->store('my_point.json');
108 my $p2 = Point->load('my_point.json');
112 MooseX::Storage is a serialization framework for Moose, it provides
113 a very flexible and highly pluggable way to serialize Moose classes
114 to a number of different formats and styles.
116 =head2 Important Note
118 This is still an early release of this module, so use with caution.
119 It's outward facing serialization API should be considered stable,
120 but I still reserve the right to make tweaks if I need too. Anything
121 beyond the basic pack/unpack, freeze/thaw and load/store should not
124 =head2 Levels of Serialization
126 There are 3 levels to the serialization, each of which builds upon
127 the other and each of which can be customized to the specific needs
134 The first (base) level is C<pack> and C<unpack>. In this level the
135 class is serialized into a Perl HASH reference, it is tagged with the
136 class name and each instance attribute is stored. Very simple.
138 This level is not optional, it is the bare minumum that
139 MooseX::Storage provides and all other levels build on top of this.
143 The second (format) level is C<freeze> and C<thaw>. In this level the
144 output of C<pack> is sent to C<freeze> or the output of C<thaw> is sent
145 to C<unpack>. This levels primary role is to convert to and from the
146 specific serialization format and Perl land.
148 This level is optional, if you don't want/need it, you don't have to
149 have it. You can just use C<pack>/C<unpack> instead.
153 The third (io) level is C<load> and C<store>. In this level we are reading
154 and writing data to file/network/database/etc.
156 This level is also optional, it does however require the C<format> level
157 to be present (at least the current state does).
161 =head2 How we serialize
163 There are always limits to any serialization framework, there are just
164 some things which are really difficult to serialize properly and some
165 things which cannot be serialized at all.
167 =head2 What can be serialized?
169 Currently only numbers, string, ARRAY refs, HASH refs and other
170 MooseX::Storage enabled objects are supported.
172 With Array and Hash references the first level down is inspected and
173 any objects found are serialized/deserialized for you. We do not do
174 this recusively by default, however this feature may become an
177 The specific serialize/deserialize routine is determined by the
178 Moose type constraint a specific attribute has. In most cases subtypes
179 of the supported types are handled correctly, and there is a facility
180 for adding handlers for custom types as well. This will get documented
181 eventually, but it is currently still in development.
183 =head2 What can not be serialized?
185 We do not support CODE references yet, but this support might be added
186 in using B::Deparse or some other deep magic.
188 Scalar refs are not supported, mostly because there is no way to know
189 if the value being referenced will be there when the object is inflated.
190 I highly doubt will be ever support this in a general sense, but it
191 would be possible to add this yourself for a small specific case.
193 Circular references are specifically disallowed, however if you break
194 the cycles yourself then re-assemble them later you can get around this.
195 The reason we disallow circular refs is because they are not always supported
196 in all formats we use, and they tend to be very tricky to do for all
197 possible cases. It is almost always something you want to have tight control
202 This is B<not> a persistence framework, changes to your object after
203 you load or store it will not be reflected in the stored class.
209 =item B<Storage (%options)>
211 This module will export the C<Storage> method will can be used to
212 load a specific set of MooseX::Storage roles to implement a specific
213 combination of features. It is meant to make things easier, but it
214 is by no means the only way. You can still compose your roles by
237 This module needs docs and probably a Cookbook of some kind as well.
238 This is an early release, so that is my excuse for now :)
240 For the time being, please read the tests and feel free to email me
241 if you have any questions. This module can also be discussed on IRC
242 in the #moose channel on irc.perl.org.
246 All complex software has bugs lurking in it, and this module is no
247 exception. If you find a bug please either email me, or add the bug
252 Chris Prather E<lt>chris.prather@iinteractive.comE<gt>
254 Stevan Little E<lt>stevan.little@iinteractive.comE<gt>
256 =head1 COPYRIGHT AND LICENSE
258 Copyright 2007 by Infinity Interactive, Inc.
260 L<http://www.iinteractive.com>
262 This library is free software; you can redistribute it and/or modify
263 it under the same terms as Perl itself.