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 with Storage('format' => 'JSON', 'io' => 'File');
69 has 'x' => (is => 'rw', isa => 'Int');
70 has 'y' => (is => 'rw', isa => 'Int');
74 my $p = Point->new(x => 10, y => 10);
76 ## methods to pack/unpack an
77 ## object in perl data structures
79 # pack the class into a hash
80 $p->pack(); # { __CLASS__ => 'Point', x => 10, y => 10 }
82 # unpack the hash into a class
83 my $p2 = Point->unpack({ __CLASS__ => 'Point', x => 10, y => 10 });
85 ## methods to freeze/thaw into
86 ## a specified serialization format
87 ## (in this case JSON)
89 # pack the class into a JSON string
90 $p->freeze(); # { "__CLASS__" : "Point", "x" : 10, "y" : 10 }
92 # unpack the JSON string into a class
93 my $p2 = Point->thaw('{ "__CLASS__" : "Point", "x" : 10, "y" : 10 }');
95 ## methods to load/store a class
98 $p->store('my_point.json');
100 my $p2 = Point->load('my_point.json');
104 MooseX::Storage is a serialization framework for Moose, it provides
105 a very flexible and highly pluggable way to serialize Moose classes
106 to a number of different formats and styles.
108 =head2 Important Note
110 This is still an early release of this module, so use with caution.
111 It's outward facing serialization API should be considered stable,
112 but I still reserve the right to make tweaks if I need too. Anything
113 beyond the basic pack/unpack, freeze/thaw and load/store should not
116 =head2 Levels of Serialization
118 There are 3 levels to the serialization, each of which builds upon
119 the other and each of which can be customized to the specific needs
126 The first (base) level is C<pack> and C<unpack>. In this level the
127 class is serialized into a Perl HASH reference, it is tagged with the
128 class name and each instance attribute is stored. Very simple.
130 This level is not optional, it is the bare minumum that
131 MooseX::Storage provides and all other levels build on top of this.
135 The second (format) level is C<freeze> and C<thaw>. In this level the
136 output of C<pack> is sent to C<freeze> or the output of C<thaw> is sent
137 to C<unpack>. This levels primary role is to convert to and from the
138 specific serialization format and Perl land.
140 This level is optional, if you don't want/need it, you don't have to
141 have it. You can just use C<pack>/C<unpack> instead.
145 The third (io) level is C<load> and C<store>. In this level we are reading
146 and writing data to file/network/database/etc.
148 This level is also optional, it does however require the C<format> level
149 to be present (at least the current state does).
153 =head2 How we serialize
155 There are always limits to any serialization framework, there are just
156 some things which are really difficult to serialize properly and some
157 things which cannot be serialized at all.
159 =head2 What can be serialized?
161 Currently only numbers, string, ARRAY refs, HASH refs and other
162 MooseX::Storage enabled objects are supported.
164 With Array and Hash references the first level down is inspected and
165 any objects found are serialized/deserialized for you. We do not do
166 this recusively by default, however this feature may become an
169 The specific serialize/deserialize routine is determined by the
170 Moose type constraint a specific attribute has. In most cases subtypes
171 of the supported types are handled correctly, and there is a facility
172 for adding handlers for custom types as well. This will get documented
173 eventually, but it is currently still in development.
175 =head2 What can not be serialized?
177 We do not support CODE references yet, but this support might be added
178 in using B::Deparse or some other deep magic.
180 Scalar refs are not supported, mostly because there is no way to know
181 if the value being referenced will be there when the object is inflated.
182 I highly doubt will be ever support this in a general sense, but it
183 would be possible to add this yourself for a small specific case.
185 Circular references are specifically disallowed, however if you break
186 the cycles yourself then re-assemble them later you can get around this.
187 The reason we disallow circular refs is because they are not always supported
188 in all formats we use, and they tend to be very tricky to do for all
189 possible cases. It is almost always something you want to have tight control
194 This is B<not> a persistence framework, changes to your object after
195 you load or store it will not be reflected in the stored class.
201 =item B<Storage (%options)>
203 This module will export the C<Storage> method will can be used to
204 load a specific set of MooseX::Storage roles to implement a specific
205 combination of features. It is meant to make things easier, but it
206 is by no means the only way. You can still compose your roles by
229 This module needs docs and probably a Cookbook of some kind as well.
230 This is an early release, so that is my excuse for now :)
232 For the time being, please read the tests and feel free to email me
233 if you have any questions. This module can also be discussed on IRC
234 in the #moose channel on irc.perl.org.
238 All complex software has bugs lurking in it, and this module is no
239 exception. If you find a bug please either email me, or add the bug
244 Chris Prather E<lt>chris.prather@iinteractive.comE<gt>
246 Stevan Little E<lt>stevan.little@iinteractive.comE<gt>
248 =head1 COPYRIGHT AND LICENSE
250 Copyright 2007 by Infinity Interactive, Inc.
252 L<http://www.iinteractive.com>
254 This library is free software; you can redistribute it and/or modify
255 it under the same terms as Perl itself.