Commit | Line | Data |
e59193fb |
1 | |
2 | package MooseX::Storage::Engine; |
3 | use Moose; |
4 | |
69b45b7d |
5 | our $VERSION = '0.02'; |
6 | our $AUTHORITY = 'cpan:STEVAN'; |
ba5bba75 |
7 | |
8 | # the class marker when |
9 | # serializing an object. |
10 | our $CLASS_MARKER = '__CLASS__'; |
11 | |
e59193fb |
12 | has 'storage' => ( |
7eb5dc63 |
13 | is => 'ro', |
14 | isa => 'HashRef', |
15 | default => sub {{}} |
16 | ); |
17 | |
18 | has 'seen' => ( |
19 | is => 'ro', |
e9739624 |
20 | isa => 'HashRef', |
e59193fb |
21 | default => sub {{}} |
22 | ); |
23 | |
e9739624 |
24 | has 'object' => (is => 'rw', isa => 'Object'); |
25 | has 'class' => (is => 'rw', isa => 'Str'); |
e59193fb |
26 | |
e9739624 |
27 | ## this is the API used by other modules ... |
e59193fb |
28 | |
29 | sub collapse_object { |
34dcaa5d |
30 | my ( $self, %options ) = @_; |
7eb5dc63 |
31 | |
32 | # NOTE: |
33 | # mark the root object as seen ... |
34 | $self->seen->{$self->object} = undef; |
35 | |
34dcaa5d |
36 | $self->map_attributes('collapse_attribute', \%options); |
c1830046 |
37 | $self->storage->{$CLASS_MARKER} = $self->object->meta->identifier; |
e59193fb |
38 | return $self->storage; |
39 | } |
40 | |
e9739624 |
41 | sub expand_object { |
219c1cc5 |
42 | my ($self, $data, %options) = @_; |
43 | |
44 | $options{check_version} = 1 unless exists $options{check_version}; |
45 | $options{check_authority} = 1 unless exists $options{check_authority}; |
7eb5dc63 |
46 | |
47 | # NOTE: |
48 | # mark the root object as seen ... |
49 | $self->seen->{$data} = undef; |
50 | |
219c1cc5 |
51 | $self->map_attributes('expand_attribute', $data, \%options); |
e9739624 |
52 | return $self->storage; |
e59193fb |
53 | } |
54 | |
e9739624 |
55 | ## this is the internal API ... |
56 | |
57 | sub collapse_attribute { |
f6e1331f |
58 | my ($self, $attr, $options) = @_; |
59 | $self->storage->{$attr->name} = $self->collapse_attribute_value($attr, $options) || return; |
e9739624 |
60 | } |
61 | |
62 | sub expand_attribute { |
219c1cc5 |
63 | my ($self, $attr, $data, $options) = @_; |
64 | $self->storage->{$attr->name} = $self->expand_attribute_value($attr, $data->{$attr->name}, $options) || return; |
e59193fb |
65 | } |
66 | |
e9739624 |
67 | sub collapse_attribute_value { |
f6e1331f |
68 | my ($self, $attr, $options) = @_; |
e9739624 |
69 | my $value = $attr->get_value($self->object); |
7eb5dc63 |
70 | |
b430caa3 |
71 | # NOTE: |
72 | # this might not be enough, we might |
73 | # need to make it possible for the |
74 | # cycle checker to return the value |
34dcaa5d |
75 | $self->check_for_cycle_in_collapse($attr, $value) |
7eb5dc63 |
76 | if ref $value; |
77 | |
e9739624 |
78 | if (defined $value && $attr->has_type_constraint) { |
3db8f791 |
79 | my $type_converter = $self->find_type_handler($attr->type_constraint); |
e9739624 |
80 | (defined $type_converter) |
81 | || confess "Cannot convert " . $attr->type_constraint->name; |
f6e1331f |
82 | $value = $type_converter->{collapse}->($value, $options); |
e9739624 |
83 | } |
84 | return $value; |
85 | } |
86 | |
87 | sub expand_attribute_value { |
219c1cc5 |
88 | my ($self, $attr, $value, $options) = @_; |
7eb5dc63 |
89 | |
b430caa3 |
90 | # NOTE: |
91 | # (see comment in method above ^^) |
45d9a73c |
92 | $self->check_for_cycle_in_expansion($attr, $value) |
7eb5dc63 |
93 | if ref $value; |
94 | |
e9739624 |
95 | if (defined $value && $attr->has_type_constraint) { |
3db8f791 |
96 | my $type_converter = $self->find_type_handler($attr->type_constraint); |
219c1cc5 |
97 | $value = $type_converter->{expand}->($value, $options); |
e9739624 |
98 | } |
99 | return $value; |
100 | } |
101 | |
b430caa3 |
102 | # NOTE: |
103 | # possibly these two methods will |
104 | # be used by a cycle supporting |
105 | # engine. However, I am not sure |
106 | # if I can make a cycle one work |
107 | # anyway. |
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108 | |
7eb5dc63 |
109 | sub check_for_cycle_in_collapse { |
45d9a73c |
110 | my ($self, $attr, $value) = @_; |
7eb5dc63 |
111 | (!exists $self->seen->{$value}) |
45d9a73c |
112 | || confess "Basic Engine does not support cycles in class(" |
c1830046 |
113 | . ($attr->associated_class->name) . ").attr(" |
45d9a73c |
114 | . ($attr->name) . ") with $value"; |
7eb5dc63 |
115 | $self->seen->{$value} = undef; |
116 | } |
117 | |
118 | sub check_for_cycle_in_expansion { |
45d9a73c |
119 | my ($self, $attr, $value) = @_; |
7eb5dc63 |
120 | (!exists $self->seen->{$value}) |
45d9a73c |
121 | || confess "Basic Engine does not support cycles in class(" |
c1830046 |
122 | . ($attr->associated_class->name) . ").attr(" |
45d9a73c |
123 | . ($attr->name) . ") with $value"; |
7eb5dc63 |
124 | $self->seen->{$value} = undef; |
125 | } |
126 | |
b430caa3 |
127 | # util methods ... |
128 | |
e9739624 |
129 | sub map_attributes { |
130 | my ($self, $method_name, @args) = @_; |
131 | map { |
132 | $self->$method_name($_, @args) |
b430caa3 |
133 | } grep { |
134 | # Skip our special skip attribute :) |
135 | !$_->isa('MooseX::Storage::Meta::Attribute::DoNotSerialize') |
e9739624 |
136 | } ($self->object || $self->class)->meta->compute_all_applicable_attributes; |
e59193fb |
137 | } |
138 | |
913d96dd |
139 | ## ------------------------------------------------------------------ |
3db8f791 |
140 | ## This is all the type handler stuff, it is in a state of flux |
141 | ## right now, so this may change, or it may just continue to be |
142 | ## improved upon. Comments and suggestions are welcomed. |
913d96dd |
143 | ## ------------------------------------------------------------------ |
144 | |
145 | # NOTE: |
146 | # these are needed by the |
147 | # ArrayRef and HashRef handlers |
148 | # below, so I need easy access |
149 | my %OBJECT_HANDLERS = ( |
150 | expand => sub { |
219c1cc5 |
151 | my ($data, $options) = @_; |
ba5bba75 |
152 | (exists $data->{$CLASS_MARKER}) |
913d96dd |
153 | || confess "Serialized item has no class marker"; |
c1830046 |
154 | # check the class more thoroughly here ... |
155 | my ($class, $version, $authority) = (split '-' => $data->{$CLASS_MARKER}); |
156 | my $meta = eval { $class->meta }; |
219c1cc5 |
157 | confess "Class ($class) is not loaded, cannot unpack" if $@; |
158 | |
159 | if ($options->{check_version}) { |
160 | my $meta_version = $meta->version; |
161 | if (defined $meta_version && $version) { |
162 | if ($options->{check_version} eq 'allow_less_than') { |
163 | ($meta_version <= $version) |
164 | || confess "Class ($class) versions is not less than currently available." |
165 | . " got=($version) available=($meta_version)"; |
166 | } |
167 | elsif ($options->{check_version} eq 'allow_greater_than') { |
168 | ($meta->version >= $version) |
169 | || confess "Class ($class) versions is not greater than currently available." |
170 | . " got=($version) available=($meta_version)"; |
171 | } |
172 | else { |
173 | ($meta->version == $version) |
174 | || confess "Class ($class) versions don't match." |
175 | . " got=($version) available=($meta_version)"; |
176 | } |
177 | } |
178 | } |
179 | |
180 | if ($options->{check_authority}) { |
181 | my $meta_authority = $meta->authority; |
182 | ($meta->authority eq $authority) |
183 | || confess "Class ($class) authorities don't match." |
184 | . " got=($authority) available=($meta_authority)" |
185 | if defined $meta_authority && defined $authority; |
186 | } |
187 | |
c1830046 |
188 | # all is well ... |
34dcaa5d |
189 | $class->unpack($data, %$options); |
913d96dd |
190 | }, |
191 | collapse => sub { |
34dcaa5d |
192 | my ( $obj, $options ) = @_; |
c4a322ec |
193 | # ($obj->can('does') && $obj->does('MooseX::Storage::Basic')) |
194 | # || confess "Bad object ($obj) does not do MooseX::Storage::Basic role"; |
1c6ac775 |
195 | ($obj->can('pack')) |
196 | || confess "Object does not have a &pack method, cannot collapse"; |
34dcaa5d |
197 | $obj->pack(%$options); |
913d96dd |
198 | }, |
199 | ); |
200 | |
201 | |
e59193fb |
202 | my %TYPES = ( |
3db8f791 |
203 | # These are boring ones, so they use the identity function ... |
e9739624 |
204 | 'Int' => { expand => sub { shift }, collapse => sub { shift } }, |
205 | 'Num' => { expand => sub { shift }, collapse => sub { shift } }, |
206 | 'Str' => { expand => sub { shift }, collapse => sub { shift } }, |
3db8f791 |
207 | # These are the trickier ones, (see notes) |
208 | # NOTE: |
209 | # Because we are nice guys, we will check |
210 | # your ArrayRef and/or HashRef one level |
211 | # down and inflate any objects we find. |
212 | # But this is where it ends, it is too |
213 | # expensive to try and do this any more |
214 | # recursively, when it is probably not |
215 | # nessecary in most of the use cases. |
216 | # However, if you need more then this, subtype |
217 | # and add a custom handler. |
913d96dd |
218 | 'ArrayRef' => { |
e9739624 |
219 | expand => sub { |
34dcaa5d |
220 | my ( $array, @args ) = @_; |
913d96dd |
221 | foreach my $i (0 .. $#{$array}) { |
222 | next unless ref($array->[$i]) eq 'HASH' |
ba5bba75 |
223 | && exists $array->[$i]->{$CLASS_MARKER}; |
34dcaa5d |
224 | $array->[$i] = $OBJECT_HANDLERS{expand}->($array->[$i], @args); |
913d96dd |
225 | } |
226 | $array; |
227 | }, |
34dcaa5d |
228 | collapse => sub { |
229 | my ( $array, @args ) = @_; |
913d96dd |
230 | # NOTE: |
231 | # we need to make a copy cause |
232 | # otherwise it will affect the |
233 | # other real version. |
234 | [ map { |
235 | blessed($_) |
34dcaa5d |
236 | ? $OBJECT_HANDLERS{collapse}->($_, @args) |
913d96dd |
237 | : $_ |
238 | } @$array ] |
239 | } |
240 | }, |
241 | 'HashRef' => { |
3db8f791 |
242 | expand => sub { |
34dcaa5d |
243 | my ( $hash, @args ) = @_; |
3db8f791 |
244 | foreach my $k (keys %$hash) { |
245 | next unless ref($hash->{$k}) eq 'HASH' |
ba5bba75 |
246 | && exists $hash->{$k}->{$CLASS_MARKER}; |
34dcaa5d |
247 | $hash->{$k} = $OBJECT_HANDLERS{expand}->($hash->{$k}, @args); |
3db8f791 |
248 | } |
249 | $hash; |
250 | }, |
251 | collapse => sub { |
34dcaa5d |
252 | my ( $hash, @args ) = @_; |
3db8f791 |
253 | # NOTE: |
254 | # we need to make a copy cause |
255 | # otherwise it will affect the |
256 | # other real version. |
257 | +{ map { |
95f31c36 |
258 | blessed($hash->{$_}) |
f6e1331f |
259 | ? ($_ => $OBJECT_HANDLERS{collapse}->($hash->{$_}, @args)) |
3db8f791 |
260 | : ($_ => $hash->{$_}) |
261 | } keys %$hash } |
262 | } |
e1bb45ff |
263 | }, |
913d96dd |
264 | 'Object' => \%OBJECT_HANDLERS, |
e1bb45ff |
265 | # NOTE: |
266 | # The sanity of enabling this feature by |
267 | # default is very questionable. |
268 | # - SL |
269 | #'CodeRef' => { |
270 | # expand => sub {}, # use eval ... |
271 | # collapse => sub {}, # use B::Deparse ... |
7eb5dc63 |
272 | #} |
e59193fb |
273 | ); |
274 | |
3db8f791 |
275 | sub add_custom_type_handler { |
276 | my ($class, $type_name, %handlers) = @_; |
277 | (exists $handlers{expand} && exists $handlers{collapse}) |
278 | || confess "Custom type handlers need an expand *and* a collapse method"; |
279 | $TYPES{$type_name} = \%handlers; |
280 | } |
281 | |
282 | sub remove_custom_type_handler { |
283 | my ($class, $type_name) = @_; |
284 | delete $TYPES{$type_name} if exists $TYPES{$type_name}; |
285 | } |
286 | |
287 | sub find_type_handler { |
e59193fb |
288 | my ($self, $type_constraint) = @_; |
e1bb45ff |
289 | |
290 | # this should handle most type usages |
291 | # since they they are usually just |
292 | # the standard set of built-ins |
293 | return $TYPES{$type_constraint->name} |
294 | if exists $TYPES{$type_constraint->name}; |
295 | |
296 | # the next possibility is they are |
297 | # a subtype of the built-in types, |
298 | # in which case this will DWIM in |
299 | # most cases. It is probably not |
300 | # 100% ideal though, but until I |
301 | # come up with a decent test case |
302 | # it will do for now. |
e59193fb |
303 | foreach my $type (keys %TYPES) { |
304 | return $TYPES{$type} |
305 | if $type_constraint->is_subtype_of($type); |
306 | } |
e1bb45ff |
307 | |
308 | # NOTE: |
309 | # the reason the above will work has to |
310 | # do with the fact that custom subtypes |
311 | # are mostly used for validation of |
312 | # the guts of a type, and not for some |
313 | # weird structural thing which would |
314 | # need to be accomidated by the serializer. |
315 | # Of course, mst or phaylon will probably |
316 | # do something to throw this assumption |
317 | # totally out the door ;) |
318 | # - SL |
319 | |
e9739624 |
320 | # NOTE: |
321 | # if this method hasnt returned by now |
322 | # then we have no been able to find a |
323 | # type constraint handler to match |
324 | confess "Cannot handle type constraint (" . $type_constraint->name . ")"; |
e59193fb |
325 | } |
326 | |
327 | 1; |
e9739624 |
328 | |
329 | __END__ |
330 | |
331 | =pod |
332 | |
ec9c1923 |
333 | =head1 NAME |
334 | |
1390c23d |
335 | MooseX::Storage::Engine - The meta-engine to handle collapsing and expanding objects |
ec9c1923 |
336 | |
337 | =head1 DESCRIPTION |
338 | |
1390c23d |
339 | No user serviceable parts inside. If you really want to know, read the source :) |
340 | |
ec9c1923 |
341 | =head1 METHODS |
342 | |
343 | =head2 Accessors |
344 | |
345 | =over 4 |
346 | |
347 | =item B<class> |
348 | |
349 | =item B<object> |
350 | |
351 | =item B<storage> |
352 | |
b430caa3 |
353 | =item B<seen> |
354 | |
ec9c1923 |
355 | =back |
356 | |
357 | =head2 API |
358 | |
359 | =over 4 |
360 | |
361 | =item B<expand_object> |
362 | |
363 | =item B<collapse_object> |
364 | |
365 | =back |
366 | |
367 | =head2 ... |
368 | |
369 | =over 4 |
370 | |
371 | =item B<collapse_attribute> |
372 | |
373 | =item B<collapse_attribute_value> |
374 | |
375 | =item B<expand_attribute> |
376 | |
377 | =item B<expand_attribute_value> |
378 | |
b430caa3 |
379 | =item B<check_for_cycle_in_collapse> |
380 | |
381 | =item B<check_for_cycle_in_expansion> |
382 | |
ec9c1923 |
383 | =item B<map_attributes> |
384 | |
3db8f791 |
385 | =back |
386 | |
387 | =head2 Type Constraint Handlers |
388 | |
389 | =over 4 |
390 | |
391 | =item B<find_type_handler> |
392 | |
393 | =item B<add_custom_type_handler> |
394 | |
395 | =item B<remove_custom_type_handler> |
ec9c1923 |
396 | |
397 | =back |
398 | |
399 | =head2 Introspection |
400 | |
401 | =over 4 |
402 | |
403 | =item B<meta> |
404 | |
405 | =back |
406 | |
407 | =head1 BUGS |
408 | |
409 | All complex software has bugs lurking in it, and this module is no |
410 | exception. If you find a bug please either email me, or add the bug |
411 | to cpan-RT. |
412 | |
413 | =head1 AUTHOR |
414 | |
415 | Chris Prather E<lt>chris.prather@iinteractive.comE<gt> |
416 | |
417 | Stevan Little E<lt>stevan.little@iinteractive.comE<gt> |
418 | |
419 | =head1 COPYRIGHT AND LICENSE |
420 | |
421 | Copyright 2007 by Infinity Interactive, Inc. |
422 | |
423 | L<http://www.iinteractive.com> |
424 | |
425 | This library is free software; you can redistribute it and/or modify |
426 | it under the same terms as Perl itself. |
427 | |
e9739624 |
428 | =cut |
429 | |
430 | |
ec9c1923 |
431 | |