3 Catalyst::Upgrading - Instructions for upgrading to the latest Catalyst
5 =head1 Upgrading to Catalyst 5.90100
7 The method C<last_error> in L</Catalyst> was actually returning the first error. This has
8 been fixed but there is a small chance it could be a breaking issue for you. If this gives
9 you trouble changing to C<shift_errors> is the easiest workaround (although that does
10 modify the error stack so if you are relying on that not being changed you should try something
11 like @{$c->errors}[-1] instead. Since this method is relatively new and the cases when the
12 error stack actually has more than one error in it, we feel the exposure is very low, but bug
13 reports are very welcomed.
15 =head1 Upgrading to Catalyst 5.90090
17 L<Catalyst::Utils> has a new method 'inject_component' which works the same as the method of
18 the same name in L<CatalystX::InjectComponent>. You should start converting any
19 use of the non core method in your code as future changes to Catalyst will be
20 sychronized to the core method first. We reserve the right to cease support
21 of the non core version should we reach a point in time where it cannot be
22 properly supported as an external module. Luckily this should be a trivial
23 search and replace. Change all occurances of:
25 CatalystX::InjectComponent->inject(...)
29 Catalyst::Utils::inject_component(...)
31 and we expect everything to work the same (we'd consider it not working the same
32 to be a bug, and please report it.)
34 We also cored features from L<CatalystX::RoleApplicator> to compose a role into the
35 request, response and stats classes. The main difference is that with L<CatalystX::RoleApplicator>
41 use CatalystX::RoleApplicator;
43 __PACKAGE__->apply_request_class_roles(
44 qw/My::Request::Role Other::Request::Role/);
46 Whereas now we have three class attributes, 'request_class_traits', 'response_class_traits'
47 and 'stats_class_traits', so you use like this (note this value is an ArrayRef)
54 __PACKAGE__->request_class_traits([qw/
56 Other::Request::Role/]);
58 (And the same for response_class_traits and stats_class_traits. We left off the
59 traits for Engine, since that class does a lot less nowadays, and dispatcher. If you
60 used those and can share a use case, we'd be likely to support them.
62 Lastly, we have some of the feature from L<CatalystX::ComponentsFromConfig> in
63 core. This should mostly work the same way in core, except for now the
64 core version does not create an automatic base wrapper class for your configured
65 components (it requires these to be catalyst components and injects them directly.
66 So if you make heavy use of custom base classes in L<CatalystX::ComponentsFromConfig>
67 you might need a bit of work to use the core version (although there is no reason
68 to stop using L<CatalystX::ComponentsFromConfig> since it should continue to work
69 fine and we'd consider issues with it to be bugs). Here's one way to map from
70 L<CatalystX::ComponentsFromConfig> to core:
72 In L<CatalystX::ComponentsFromConfig>:
84 inject_components => {
85 'Model::MyClass' => { from_component => 'My::Class' },
92 Although the cored behavior requires more code, its better separates concerns
93 as well as plays more into core Catalyst expections of how configuration shoul
96 Also we added a new develop console mode only warning when you call a component
97 with arguments that don't expect or do anything meaningful with those args. Its
98 possible if you are logging debug mode in production (please don't...) this
99 could add verbosity to those logs if you also happen to be calling for components
100 and passing pointless arguments. We added this warning to help people not make this
101 error and to better understand the component resolution flow.
103 =head1 Upgrading to Catalyst 5.90085
105 In this version of Catalyst we made a small change to Chained Dispatching so
106 that when two or more actions all have the same path specification AND they
107 all have Args(0), we break the tie by choosing the last action defined, and
108 not the first one defined. This was done to normalize Chaining to following
109 the 'longest Path wins, and when several actions match the same Path specification
110 we choose the last defined.' rule. Previously Args(0) was hard coded to be a special
111 case such that the first action defined would match (which is not the case when
114 Its possible that this could be a breaking change for you, if you had used
115 action roles (custom or otherwise) to add additional matching rules to differentiate
116 between several Args(0) actions that share the same root action chain. For
117 example if you have code now like this:
119 sub check_default :Chained(/) CaptureArgs(0) { ... }
121 sub default_get :Chained('check_default') PathPart('') Args(0) GET {
122 pop->res->body('get3');
125 sub default_post :Chained('check_default') PathPart('') Args(0) POST {
126 pop->res->body('post3');
129 sub chain_default :Chained('check_default') PathPart('') Args(0) {
130 pop->res->body('chain_default');
133 The way that chaining will work previous is that when two or more equal actions can
134 match, the 'top' one wins. So if the request is "GET .../check_default" BOTH
135 actions 'default_get' AND 'chain_default' would match. To break the tie in
136 the case when Args is 0, we'd previous take the 'top' (or first defined) action.
137 Unfortunately this treatment of Args(0) is special case. In all other cases
138 we choose the 'last defined' action to break a tie. So this version of
139 Catalyst changed the dispatcher to make Args(0) no longer a special case for
140 breaking ties. This means that the above code must now become:
142 sub check_default :Chained(/) CaptureArgs(0) { ... }
144 sub chain_default :Chained('check_default') PathPart('') Args(0) {
145 pop->res->body('chain_default');
148 sub default_get :Chained('check_default') PathPart('') Args(0) GET {
149 pop->res->body('get3');
152 sub default_post :Chained('check_default') PathPart('') Args(0) POST {
153 pop->res->body('post3');
156 If we want it to work as expected (for example we we GET to match 'default_get' and
157 POST to match 'default_post' and any other http Method to match 'chain_default').
159 In other words Arg(0) and chained actions must now follow the normal rule where
160 in a tie the last defined action wins and you should place all your less defined
161 or 'catch all' actions first.
163 If this causes you trouble and you can't fix your code to conform, you may set the
164 application configuration setting "use_chained_args_0_special_case" to true and
165 that will revert you code to the previous behavior.
167 =head2 More backwards compatibility options with UTF-8 changes
169 In order to give better backwards compatiblity with the 5.90080+ UTF-8 changes
170 we've added several configuration options around control of how we try to decode
171 your URL keywords / query parameters.
173 C<do_not_decode_query>
175 If true, then do not try to character decode any wide characters in your
176 request URL query or keywords. Most readings of the relevent specifications
177 suggest these should be UTF-* encoded, which is the default that L<Catalyst>
178 will use, hwoever if you are creating a lot of URLs manually or have external
179 evil clients, this might cause you trouble. If you find the changes introduced
180 in Catalyst version 5.90080+ break some of your query code, you may disable
181 the UTF-8 decoding globally using this configuration.
183 This setting takes precedence over C<default_query_encoding> and
184 C<decode_query_using_global_encoding>
186 C<default_query_encoding>
188 By default we decode query and keywords in your request URL using UTF-8, which
189 is our reading of the relevent specifications. This setting allows one to
190 specify a fixed value for how to decode your query. You might need this if
191 you are doing a lot of custom encoding of your URLs and not using UTF-8.
193 This setting take precedence over C<decode_query_using_global_encoding>.
195 C<decode_query_using_global_encoding>
197 Setting this to true will default your query decoding to whatever your
198 general global encoding is (the default is UTF-8).
201 =head1 Upgrading to Catalyst 5.90080
203 UTF8 encoding is now default. For temporary backwards compatibility, if this
204 change is causing you trouble, you can disable it by setting the application
205 configuration option to undef:
207 MyApp->config(encoding => undef);
209 But please consider this a temporary measure since it is the intention that
210 UTF8 is enabled going forwards and the expectation is that other ecosystem
211 projects will assume this as well. At some point you application will not
212 correctly function without this setting.
214 As of 5.90084 we've added two additional configuration flags for more selective
215 control over some encoding changes: 'skip_body_param_unicode_decoding' and
216 'skip_complex_post_part_handling'. You may use these to more selectively
217 disable new features while you are seeking a long term fix. Please review
218 CONFIGURATION in L<Catalyst>.
220 For further information, please see L<Catalyst::UTF8>
222 A number of projects in the wider ecosystem required minor updates to be able
223 to work correctly. Here's the known list:
225 L<Catalyst::View::TT>, L<Catalyst::View::Mason>, L<Catalyst::View::HTML::Mason>,
226 L<Catalyst::View::Xslate>, L<Test::WWW::Mechanize::Catalyst>
228 You will need to update to modern versions in most cases, although quite a few
229 of these only needed minor test case and documentation changes so you will need
230 to review the changelog of each one that is relevant to you to determine your
233 =head1 Upgrading to Catalyst 5.90060
235 Starting in the v5.90059_001 development release, the regexp dispatch type is
236 no longer automatically included as a dependency. If you are still using this
237 dispatch type, you need to add L<Catalyst::DispatchType::Regex> into your build
240 The standalone distribution of Regexp will be supported for the time being, but
241 should we find that supporting it prevents us from moving L<Catalyst> forward
242 in necessary ways, we reserve the right to drop that support. It is highly
243 recommended that you use this last stage of deprecation to change your code.
245 =head1 Upgrading to Catalyst 5.90040
247 =head2 Catalyst::Plugin::Unicode::Encoding is now core
249 The previously stand alone Unicode support module L<Catalyst::Plugin::Unicode::Encoding>
250 has been brought into core as a default plugin. Going forward, all you need is
251 to add a configuration setting for the encoding type. For example:
257 __PACKAGE__->config( encoding => 'UTF-8' );
259 Please note that this is different from the old stand alone plugin which applied
260 C<UTF-8> encoding by default (that is, if you did not set an explicit
261 C<encoding> configuration value, it assumed you wanted UTF-8). In order to
262 preserve backwards compatibility you will need to explicitly turn it on via the
263 configuration setting. THIS MIGHT CHANGE IN THE FUTURE, so please consider
264 starting to test your application with proper UTF-8 support and remove all those
265 crappy hacks you munged into the code because you didn't know the Plugin
268 For people that are using the Plugin, you will note a startup warning suggesting
269 that you can remove it from the plugin list. When you do so, please remember to
270 add the configuration setting, since you can no longer rely on the default being
271 UTF-8. We'll add it for you if you continue to use the stand alone plugin and
272 we detect this, but this backwards compatibility shim will likely be removed in
273 a few releases (trying to clean up the codebase after all).
275 If you have trouble with any of this, please bring it to the attention of the
276 Catalyst maintainer group.
278 =head2 basic async and event loop support
280 This version of L<Catalyst> offers some support for using L<AnyEvent> and
281 L<IO::Async> event loops in your application. These changes should work
282 fine for most applications however if you are already trying to perform
283 some streaming, minor changes in this area of the code might affect your
284 functionality. Please see L<Catalyst::Response\write_fh> for more and for a
287 We consider this feature experimental. We will try not to break it, but we
288 reserve the right to make necessary changes to fix major issues that people
289 run into when the use this functionality in the wild.
291 =head1 Upgrading to Catalyst 5.90030
293 =head2 Regex dispatch type is deprecated.
295 The Regex dispatchtype (L<Catalyst::DispatchType::Regex>) has been deprecated.
297 You are encouraged to move your application to Chained dispatch (L<Catalyst::DispatchType::Chained>).
299 If you cannot do so, please add a dependency to Catalyst::DispatchType::Regex to your application's
302 =head1 Upgrading to Catalyst 5.9
304 The major change is that L<Plack>, a toolkit for using the L<PSGI>
305 specification, now replaces most of the subclasses of L<Catalyst::Engine>. If
306 you are using one of the standard subclasses of L<Catalyst::Engine> this
307 should be a straightforward upgrade for you. It was a design goal for
308 this release to preserve as much backwards compatibility as possible.
309 However, since L<Plack> is different from L<Catalyst::Engine>, it is
310 possible that differences exist for edge cases. Therefore, we recommend
311 that care be taken with this upgrade and that testing should be greater
312 than would be the case with a minor point update. Please inform the
313 Catalyst developers of any problems so that we can fix them and
316 It is highly recommended that you become familiar with the L<Plack> ecosystem
317 and documentation. Being able to take advantage of L<Plack> development and
318 middleware is a major bonus to this upgrade. Documentation about how to
319 take advantage of L<Plack::Middleware> by writing your own C<< .psgi >> file
320 is contained in L<Catalyst::PSGI>.
322 If you have created a custom subclass of L<Catalyst:Engine>, you will
323 need to convert it to be a subclass of L<Plack::Handler>.
325 If you are using the L<Plack> engine, L<Catalyst::Engine::PSGI>, this new
326 release supersedes that code.
328 If you are using a subclass of L<Catalyst::Engine> that is aimed at
329 nonstandard or internal/testing uses, such as
330 L<Catalyst::Engine::Embeddable>, you should still be able to continue
333 Advice for specific subclasses of L<Catalyst::Engine> follows:
335 =head2 Upgrading the FastCGI Engine
337 No upgrade is needed if your myapp_fastcgi.pl script is already upgraded
338 to use L<Catalyst::Script::FastCGI>.
340 =head2 Upgrading the mod_perl / Apache Engines
342 The engines that are built upon the various iterations of mod_perl,
343 L<Catalyst::Engine::Apache::MP13> (for mod_perl 1, and Apache 1.x) and
344 L<Catalyst::Engine::Apache2::MP20> (for mod_perl 2, and Apache 2.x),
345 should be seamless upgrades and will work using L<Plack::Handler::Apache1>
346 or L<Plack::Handler::Apache2> as required.
348 L<Catalyst::Engine::Apache2::MP19>, however, is no longer supported, as
349 Plack does not support mod_perl version 1.99. This is unlikely to be a
350 problem for anyone, as 1.99 was a brief beta-test release for mod_perl
351 2, and all users of mod_perl 1.99 are encouraged to upgrade to a
352 supported release of Apache 2 and mod_perl 2.
354 =head2 Upgrading the HTTP Engine
356 The default development server that comes with the L<Catalyst> distribution
357 should continue to work as expected with no changes as long as your C<myapp_server>
358 script is upgraded to use L<Catalyst::Script::HTTP>.
360 =head2 Upgrading the CGI Engine
362 If you were using L<Catalyst::Engine::CGI> there is no upgrade needed if your
363 myapp_cgi.pl script is already upgraded to use L<Catalyst::Script::CGI>.
365 =head2 Upgrading Catalyst::Engine::HTTP::Prefork
367 If you were using L<Catalyst::Engine::HTTP::Prefork> then L<Starman>
368 is automatically loaded. You should (at least) change your C<Makefile.PL>
369 to depend on Starman.
371 You can regenerate your C<myapp_server.pl> script with C<catalyst.pl>
372 and implement a C<MyApp::Script::Server> class that looks like this:
374 package MyApp::Script::Server;
376 use namespace::autoclean;
378 extends 'CatalystX::Script::Server::Starman';
382 This takes advantage of the new script system, and will add a number of
383 options to the standard server script as extra options are added by
386 More information about these options can be seen at
387 L<CatalystX::Script::Server::Starman/SYNOPSIS>.
389 An alternate route to implement this functionality is to write a simple .psgi
390 file for your application, and then use the L<plackup> utility to start the
393 =head2 Upgrading the PSGI Engine
395 If you were using L<Catalyst::Engine::PSGI>, this new release supersedes
396 this engine in supporting L<Plack>. By default the Engine is now always
397 L<Plack>. As a result, you can remove the dependency on
398 L<Catalyst::Engine::PSGI> in your C<Makefile.PL>.
400 Applications that were using L<Catalyst::Engine::PSGI>
401 previously should entirely continue to work in this release with no changes.
403 However, if you have an C<app.psgi> script, then you no longer need to
404 specify the PSGI engine. Instead, the L<Catalyst> application class now
405 has a new method C<psgi_app> which returns a L<PSGI> compatible coderef
406 which you can wrap in the middleware of your choice.
408 Catalyst will use the .psgi for your application if it is located in the C<home>
409 directory of the application.
411 For example, if you were using L<Catalyst::Engine::PSGI> in the past, you will
412 have written (or generated) a C<script/myapp.psgi> file similar to this one:
417 MyCatalystApp->setup_engine('PSGI');
420 enable ... # enable your desired middleware
421 sub { MyCatalystApp->run(@_) };
424 Instead, you now say:
430 enable ... #enable your desired middleware
431 MyCatalystApp->psgi_app;
434 In the simplest case:
436 MyCatalystApp->setup_engine('PSGI');
437 my $app = sub { MyCatalystApp->run(@_) }
441 my $app = MyCatalystApp->psgi_app(@_);
445 my $app = sub { MyCatalystApp->psgi_app(@_) };
446 # If you make ^^ this mistake, your app won't work, and will confuse the hell out of you!
448 You can now move C<< script/myapp.psgi >> to C<< myapp.psgi >>, and the built-in
449 Catalyst scripts and your test suite will start using your .psgi file.
451 B<NOTE:> If you rename your .psgi file without these modifications, then
452 any tests run via L<Catalyst::Test> will not be compatible with the new
453 release, and will result in the development server starting, rather than
454 the expected test running.
456 B<NOTE:> If you are directly accessing C<< $c->req->env >> to get the PSGI
457 environment then this accessor is moved to C<< $c->engine->env >>,
458 you will need to update your code.
460 =head2 Engines which are known to be broken
462 The following engines B<DO NOT> work as of Catalyst version 5.9. The
463 core team will be happy to work with the developers and/or users of
464 these engines to help them port to the new Plack/Engine system, but for
465 now, applications which are currently using these engines B<WILL NOT>
466 run without modification to the engine code.
470 =item Catalyst::Engine::Wx
472 =item Catalyst::Engine::Zeus
474 =item Catalyst::Engine::JobQueue::POE
476 =item Catalyst::Engine::XMPP2
478 =item Catalyst::Engine::SCGI
482 =head2 Engines with unknown status
484 The following engines are untested or have unknown compatibility.
485 Reports are highly encouraged:
489 =item Catalyst::Engine::Mojo
491 =item Catalyst::Engine::Server (marked as Deprecated)
493 =item Catalyst::Engine::HTTP::POE (marked as Deprecated)
497 =head2 Plack functionality
499 See L<Catalyst::PSGI>.
503 Tests should generally work the same in Catalyst 5.9, but there are
506 Previously, if using L<Catalyst::Test> and doing local requests (against
507 a local server), if the application threw an exception then this
508 exception propagated into the test.
510 This behavior has been removed, and now a 500 response will be returned
511 to the test. This change standardizes behavior, so that local test
512 requests behave similarly to remote requests.
514 =head1 Upgrading to Catalyst 5.80
516 Most applications and plugins should run unaltered on Catalyst 5.80.
518 However, a lot of refactoring work has taken place, and several changes have
519 been made which could cause incompatibilities. If your application or plugin
520 is using deprecated code, or relying on side effects, then you could have
521 issues upgrading to this release.
523 Most issues found with existing components have been easy to
524 solve. This document provides a complete description of behavior changes
525 which may cause compatibility issues, and of new Catalyst warnings which
528 If you think you have found an upgrade-related issue which is not covered in
529 this document, please email the Catalyst list to discuss the problem.
531 =head1 Moose features
533 =head2 Application class roles
535 You can only apply method modifiers after the application's C<< ->setup >>
536 method has been called. This means that modifiers will not work with methods
537 run during the call to C<< ->setup >>.
539 See L<Catalyst::Manual::ExtendingCatalyst> for more information about using
540 L<Moose> in your applications.
542 =head2 Controller actions in Moose roles
544 You can use L<MooseX::MethodAttributes::Role> if you want to declare actions
547 =head2 Using Moose in Components
549 The correct way to use Moose in a component in a both forward and backwards
552 package TestApp::Controller::Root;
554 BEGIN { extends 'Catalyst::Component' }; # Or ::Controller, or whatever
556 See L<Components which inherit from Moose::Object before Catalyst::Component>.
558 =head1 Known backwards compatibility breakages
560 =head2 Applications in a single file
562 Applications must be in their own file, and loaded at compile time. This
563 issue generally only affects the tests of CPAN distributions. Your
564 application will fail if you try to define an application inline in a
565 block, and use plugins which supply a C< new > method, then use that
566 application latter in tests within the same file.
568 This is due to the fact that Catalyst is inlining a new method on your
569 application class allowing it to be compatible with Moose. The method
570 used to do this changed in 5.80004 to avoid the possibility of reporting
571 an 'Unknown Error' if your application failed to compile.
573 =head2 Issues with Class::C3
575 Catalyst 5.80 uses the L<Algorithm::C3> method dispatch order. This is
576 built into Perl 5.10, and comes via L<Class::C3> for Perl 5.8. This
577 replaces L<NEXT> with L<Class::C3::Adopt::NEXT>, forcing all components
578 to resolve methods using C3, rather than the unpredictable dispatch
581 This issue manifests itself by your application failing to start due to an
582 error message about having a non-linear @ISA.
584 The Catalyst plugin most often causing this is
585 L<Catalyst::Plugin::Session::Store::FastMmap> - if you are using this
586 plugin and see issues, then please upgrade your plugins, as it has been
587 fixed. Note that Makefile.PL in the distribution will warn about known
588 incompatible components.
590 This issue can, however, be found in your own application - the only solution is
591 to go through each base class of the class the error was reported against, until
592 you identify the ones in conflict, and resolve them.
594 To be able to generate a linear @ISA, the list of superclasses for each
595 class must be resolvable using the C3 algorithm. Unfortunately, when
596 superclasses are being used as mixins (to add functionality used in your class),
597 and with multiple inheritance, it is easy to get this wrong.
599 Most common is the case of:
601 package Component1; # Note, this is the common case
602 use base qw/Class::Accessor::Fast Class::Data::Inheritable/;
604 package Component2; # Accidentally saying it this way causes a failure
605 use base qw/Class::Data::Inheritable Class::Accessor::Fast/;
608 use base qw/Component1 Component2/;
610 Any situation like this will cause your application to fail to start.
612 For additional documentation about this issue, and how to resolve it, see
613 L<Class::C3::Adopt::NEXT>.
615 =head2 Components which inherit from Moose::Object before Catalyst::Component
617 Moose components which say:
619 package TestApp::Controller::Example;
621 extends qw/Moose::Object Catalyst::Component/;
623 to use the constructor provided by Moose, while working (if you do some hacks
624 with the C< BUILDARGS > method), will not work with Catalyst 5.80 as
625 C<Catalyst::Component> inherits from C<Moose::Object>, and so C< @ISA > fails
628 The correct way to use Moose in a component in a both forward and backwards
631 package TestApp::Controller::Root;
633 BEGIN { extends 'Catalyst::Component' }; # Or ::Controller, or whatever
635 Note that the C< extends > declaration needs to occur in a begin block for
636 L<attributes> to operate correctly.
638 This way you do not inherit directly from C<Moose::Object>
639 yourself. Having components which do not inherit their constructor from
640 C<Catalyst::Component> is B<unsupported>, and has never been recommended,
641 therefore you're on your own if you're using this technique. You'll need
642 to detect the version of Catalyst your application is running, and deal
643 with it appropriately.
645 You also don't get the L<Moose::Object> constructor, and therefore attribute
646 initialization will not work as normally expected. If you want to use Moose
647 attributes, then they need to be made lazy to correctly initialize.
649 Note that this only applies if your component needs to maintain component
650 backwards compatibility for Catalyst versions before 5.71001 - in 5.71001
651 attributes work as expected, and the BUILD method is called normally
652 (although BUILDARGS is not).
654 If you depend on Catalyst 5.8, then B<all> Moose features work as expected.
656 You will also see this issue if you do the following:
658 package TestApp::Controller::Example;
660 use base 'Catalyst::Controller';
662 as C< use base > appends to @ISA.
664 =head3 use Moose in MyApp
666 Similar to the above, this will also fail:
675 If you need to use Moose in your application class (e.g. for method modifiers
676 etc.) then the correct technique is:
684 __PACKAGE__->config( name => 'MyApp' );
685 __PACKAGE__->setup(qw/
689 =head2 Anonymous closures installed directly into the symbol table
691 If you have any code which installs anonymous subroutine references directly
692 into the symbol table, you may encounter breakages. The simplest solution is
693 to use L<Sub::Name> to name the subroutine. Example:
695 # Original code, likely to break:
696 my $full_method_name = join('::', $package_name, $method_name);
697 *$full_method_name = sub { ... };
700 use Sub::Name 'subname';
701 my $full_method_name = join('::',$package_name, $method_name);
702 *$full_method_name = subname $full_method_name, sub { ... };
704 Additionally, you can take advantage of Catalyst's use of L<Class::MOP> and
705 install the closure using the appropriate metaclass. Example:
708 my $metaclass = Moose::Meta::Class->initialize($package_name);
709 $metaclass->add_method($method_name => sub { ... });
711 =head2 Hooking into application setup
713 To execute code during application start-up, the following snippet in MyApp.pm
717 my ($class, @args) = @_;
718 $class->NEXT::setup(@args);
719 ... # things to do after the actual setup
722 With Catalyst 5.80 this won't work anymore, because Catalyst no longer
723 uses NEXT.pm for method resolution. The functionality was only ever
724 originally operational as L<NEXT> remembers what methods have already
725 been called, and will not call them again.
727 Using this now causes infinite recursion between MyApp::setup and
728 Catalyst::setup, due to other backwards compatibility issues related to how
729 plugin setup works. Moose method modifiers like C<< before|after|around setup
730 => sub { ... }; >> also will not operate correctly on the setup method.
732 The right way to do it is this:
734 after setup_finalize => sub {
735 ... # things to do after the actual setup
738 The setup_finalize hook was introduced as a way to avoid this issue.
740 =head2 Components with a new method which returns false
742 Previously, if you had a component which inherited from Catalyst::COMPONENT,
743 but overrode the new method to return false, then your class's configuration
744 would be blessed into a hash on your behalf, and this would be returned from
745 the COMPONENT method.
747 This behavior makes no sense, and so has been removed. Implementing your own
748 C< new > method in components is B<highly> discouraged. Instead, you should
749 inherit the new method from Catalyst::Component, and use Moose's BUILD
750 functionality and/or Moose attributes to perform any construction work
751 necessary for your class.
753 =head2 __PACKAGE__->mk_accessor('meta');
755 Won't work due to a limitation of L<Moose>. This is currently being fixed
758 =head2 Class::Data::Inheritable side effects
760 Previously, writing to a class data accessor would copy the accessor method
761 down into your package.
763 This behavior has been removed. While the class data is still stored
764 per-class, it is stored on the metaclass of the class defining the accessor.
766 Therefore anything relying on the side effect of the accessor being copied down
769 The following test demonstrates the problem:
773 use base qw/Class::Data::Inheritable/;
774 __PACKAGE__->mk_classdata('foo');
779 use base qw/BaseClass/;
782 BaseClass->foo('base class');
783 Child->foo('sub class');
786 isnt(BaseClass->can('foo'), Child->can('foo'));
788 =head2 Extending Catalyst::Request or other classes in an ad hoc manner using mk_accessors
790 Previously, it was possible to add additional accessors to Catalyst::Request
791 (or other classes) by calling the mk_accessors class method.
793 This is no longer supported - users should make a subclass of the class whose
794 behavior they would like to change, rather than globally polluting the
797 =head2 Confused multiple inheritance with Catalyst::Component::COMPONENT
799 Previously, Catalyst's COMPONENT method would delegate to the method on
800 the right hand side, which could then delegate back again with
801 NEXT. This is poor practice, and in addition, makes no sense with C3
802 method dispatch order, and is therefore no longer supported.
804 If a COMPONENT method is detected in the inheritance hierarchy to the right
805 hand side of Catalyst::Component::COMPONENT, then the following warning
806 message will be emitted:
808 There is a COMPONENT method resolving after Catalyst::Component
811 The correct fix is to re-arrange your class's inheritance hierarchy so that the
812 COMPONENT method you would like to inherit is the first (left-hand most)
813 COMPONENT method in your @ISA.
815 =head2 Development server relying on environment variables
817 Previously, the development server would allow propagation of system
818 environment variables into the request environment, this has changed with the
819 adoption of Plack. You can use L<Plack::Middleware::ForceEnv> to achieve the
824 =head2 Actions in your application class
826 Having actions in your application class will now emit a warning at application
827 startup as this is deprecated. It is highly recommended that these actions are moved
828 into a MyApp::Controller::Root (as demonstrated by the scaffold application
829 generated by catalyst.pl).
831 This warning, also affects tests. You should move actions in your test,
832 creating a myTest::Controller::Root, like the following example:
834 package MyTest::Controller::Root;
839 use parent 'Catalyst::Controller';
841 __PACKAGE__->config(namespace => '');
844 my ( $self, $c ) = @_;
850 =head2 ::[MVC]:: naming scheme
852 Having packages called MyApp::[MVC]::XX is deprecated and can no longer be generated
855 This is still supported, but it is recommended that you rename your application
856 components to Model/View/Controller.
858 A warning will be issued at application startup if the ::[MVC]:: naming scheme is
861 =head2 Catalyst::Base
863 Any code using L<Catalyst::Base> will now emit a warning; this
864 module will be removed in a future release.
866 =head2 Methods in Catalyst::Dispatcher
868 The following methods in Catalyst::Dispatcher are implementation
869 details, which may change in the 5.8X release series, and therefore their use
870 is highly deprecated.
878 =item registered_dispatch_types
880 =item method_action_class
888 The first time one of these methods is called, a warning will be emitted:
890 Class $class is calling the deprecated method Catalyst::Dispatcher::$public_method_name,
891 this will be removed in Catalyst 5.9
893 You should B<NEVER> be calling any of these methods from application code.
895 Plugin authors and maintainers whose plugins currently call these methods
896 should change to using the public API, or, if you do not feel the public API
897 adequately supports your use case, please email the development list to
898 discuss what API features you need so that you can be appropriately supported.
900 =head2 Class files with names that don't correspond to the packages they define
902 In this version of Catalyst, if a component is loaded from disk, but no
903 symbols are defined in that component's name space after it is loaded, this
904 warning will be issued:
906 require $class was successful but the package is not defined.
908 This is to protect against confusing bugs caused by mistyping package names,
909 and will become a fatal error in a future version.
911 Please note that 'inner packages' (via L<Devel::InnerPackage>) are still fully
912 supported; this warning is only issued when component file naming does not map
913 to B<any> of the packages defined within that component.
915 =head2 $c->plugin method
917 Calling the plugin method is deprecated, and calling it at run time is B<highly
920 Instead you are recommended to use L<Catalyst::Model::Adaptor> or similar to
921 compose the functionality you need outside of the main application name space.
923 Calling the plugin method will not be supported past Catalyst 5.81.