X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FUpgrading.pod;h=6b160fab8f02145fad204e61b6ee5e0d5c570f64;hb=a87f5aa5d65bb8f46afaaa08c26502962c9311ff;hp=d7a3266518c81c42af80638f04d54f7d504715ad;hpb=c571d2c84b0acd26c540bba4b604e7ce8e01e426;p=catagits%2FCatalyst-Runtime.git diff --git a/lib/Catalyst/Upgrading.pod b/lib/Catalyst/Upgrading.pod index d7a3266..6b160fa 100644 --- a/lib/Catalyst/Upgrading.pod +++ b/lib/Catalyst/Upgrading.pod @@ -1,23 +1,59 @@ =head1 Upgrading to Catalyst 5.80 -Work in progress +Most applications and plugins should run unaltered on Catalyst 5.80. + +However as a lot of refactoring work has taken place, several changes +have been made which could cause incompatibilities, if your application +or plugin is using deprecated code, or relying on side-effects then +there could be incompatibility. + +Most issues found with pre-existing components have been easy to solve, +and a complete description of behavior changes which may cause compatibility +issues, or warnings to be emitted is included below to help if you have +problems. + +If you think you have found an upgrade related issue which is not covered in +this document, then please email the Catalyst list to discuss the problem. =head1 Known backwards compatibility breakages. -=head2 Catalyst::Plugin::Authentication +=head2 Components which inherit from Moose::Object before Catalyst::Component + +Moose components which say: + + package TestApp::Controller::Example; + use Moose; + extends qw/Moose::Object Catalyst::Component/; + +to use the constructor provided by Moose, whilst working if you do some hacks +with the C< BUILDARGS > method, will not work with Catalyst 5.80 as +C inherits from C, and so C< @ISA > fails +to linearise. -You need at least version FIXME of Catalyst::Plugin::Authentication. +The fix for this, is to not inherit directly from C +yourself. Having components which do not inherit their constructor from +C is B, and has never been recommended, +therefore you're on your own if you're using this technique. You'll need +to detect the version of Catalyst your application is running with and deal +with it appropriately. -=head2 Moose applications +You will also see this issue if you do the following: -Applications made by early adopters, which say: + package TestApp::Controller::Example; + use Moose; + use base 'Catalyst::Controller'; - extends qw/Moose::Object Catalyst::Component/ +as C< use base > appends to @ISA. -need the C removing to run with Catalyst 5.80, otherwise -your Class' @ISA will not linearise with C3. +The correct way to use Moose in a component in a both forward and backwards +compatible way is: -rafl to fix this bit :) + package TestApp::Controller::Root; + use Moose; + BEGIN { extends 'Catalyst::Component' }; # Or ::Controller, or whatever + +Note that the C< extends > decleration needs to occur in a begin block for +L to operate correctly. =head2 Anonymous closures installed directly into the symbol table @@ -41,63 +77,127 @@ install the closure using the appropriate metaclass. Example: my $metaclass = Moose::Meta::Class->initialize($package_name); $metaclass->add_method($method_name => sub { ... }); -=head2 Components without new methods +=head2 Hooking into application setup + +To execute code during application startup the following snippet in MyApp.pm +used to work: + + sub setup { + my ($class, @args) = @_; + $class->NEXT::setup(@args); + ... # things to do after the actual setup + } + +With Catalyst 5.80 this won't work anymore. Because instead of using NEXT.pm it +relies on Class::C3::Adopt::NEXT, which doesn't remember what methods it +already called, like NEXT does and therefore goes into a deep recursion between +MyApp::setup and Catalyst::setup. + +Moose method modifiers line C<< before|after|around 'setup => sub { ... }; >> +won't work either because of backward compatibility issues related to plugin +setup methods. + +The right way to do it is this: -FIXME + after setup_finalize => sub { + ... # things to do after the actual setup + }; -=head2 Components without COMPONENT methods +=head2 Components whos new method returns false -FIXME +Previously, if you had a component which inherited from Catalyst::COMPONENT, +but overrode the new method, to return false, then your class' configuration +would be blessed into a hash on your behalf, and this would be returned from +the COMPONENT method. + +This behaviour makes no sense, and so has been removed.. You are recommended to +implement your own new method in components, instead, you should inherit the +new method from Catalyst::Component, and use Moose's BUILD functionality to +perform any construction work necessary for your sub-class. =head2 __PACKAGE__->mk_accessor('meta'); -Won't work due to a limitation of L +Won't work due to a limitation of L -FIXME +This is currently being fixed inside core Moose. =head2 Class::Data::Inheritable side effects -FIXME +Previously, writing to a class data accessor would copy the accessor method +down into your package. -=head2 Extending Catalyst::Request or other classes in an ad-hoc manor using mk_accessor +This behavior has been removed. Whilst the class data is still stored +per-class, it is stored on the metaclass of the class defining the accessor. -FIXME +Therefore anything relying on the side-effect of the accessor being copied down +will be broken. -=head2 require $class was successful but the package is not defined. +The following example demonstrates the problem: -FIXME Warning + { + package BaseClass; + use base qw/Class::Data::Inheritable/; + __PACKAGE__->mk_classdata('foo'); + } -=head2 $c->plugin method + { + package Child; + use base qw/BaseClass/; + } -Deprecated + BaseClass->foo('base class'); + Child->foo('sub class'); -=head2 Components which inherit Catalyst::Component's COMPONENT method, who's new method does not return a true value. + isnt(BaseClass->can('foo'), Child->can('foo')); -Previously if your new method returned a false value, then your class' configuration would be blessed into a hash on your behalf, -and this would be returned from the COMPONENT method. This is no longer supported. You are not recommended to implement your own new method -in components, instead, you should inherit the new method from Catalyst::Component, and use Moose's BUILD functionality -to perform any construction work necessary for your sub-class. +=head2 Extending Catalyst::Request or other classes in an ad-hoc manor using mk_accessors +Previously, it was possible to add additional accessors to Catalyst::Request +(or other classes) by calling the mk_accessors class method. + +This is no longer supported - users should make a sub-class of the class who's +behavior they would like to change, rather than globally polluting the Catalyst +objects. + +=head2 Confused multiple inheritance with Catalyst::Component::COMPONENT + +Warning message: + + There is a COMPONENT method resolving after Catalyst::Component + in ${next_package}. + +This means that one of the packages on the right hand side of +Catalyst::Component in your Class' inheritance hierarchy defines +a COMPONENT method. + +Previously, Catalyst's COMPONENT method would delegate to the +method on the right hand side, which could then delegate back again +with NEXT. This (as it is insane), is no longer supported, as it +makes no sense with C3 method dispatch order. + +Therefore the correct fix is to re-arrange your class' inheritance +hierarchy so that the COMPONENT method you would like to inherit is +the first COMPONENT method in your @ISA. =head1 WARNINGS =head2 Methods in Catalyst::Dispatcher -The following methods in Catalyst::Dispatcher are likely to change +The following methods in Catalyst::Dispatcher are likely to change significantly in the 5.8X release series, and therefore their use is highly deprecated. =over -=item tree +=item tree -=item dispatch_types +=item dispatch_types -=item registered_dispatch_types +=item registered_dispatch_types -=item method_action_class +=item method_action_class -=item action_hash +=item action_hash =item container_hash @@ -110,29 +210,26 @@ The first time one of these methods is called, a warning will be emitted: You should B be calling any of these methods from application code. -Plugins authors and maintainers whos plugins need to call these methods -should email the development list to discuss your use-case, and what a -better API should look like. +Plugins authors and maintainers whos plugins need to call these methods should +email the development list to discuss your use-case, and what a better API +should look like. -=head2 Confused multiple inheritence with Catalyst::Component::COMPONENT +=head2 require $class was successful but the package is not defined. -Warning message: +In this version of Catalyst, if a component is loaded from disk, but no symbols +are defined in that component's namespace after it is loaded, this warning will +be issued. - There is a COMPONENT method resolving after Catalyst::Component - in ${next_package}. - -This means that one of the packages on the right hand side of -Catalyst::Component in your Class' inheritance hierarchy defines -a COMPONENT method. +This is to protect against confusing bugs caused by mis-typing package names. -Previously, Catalyst's COMPONENT method would delegate to the -method on the right hand side, which could then delegate back again -with NEXT. This (as it is insane), is no longer supported, as it -makes no sense with C3 method dispatch order. +This will become a fatal error in a future version. -Therefore the correct fix is to re-arrange your class' inheritance -hierarchy so that the COMPONENT method you would like to inherit is -the first COMPONENT method in your @ISA. +=head2 $c->plugin method + +Calling the plugin method is deprecated, and calling it at runtime is B. +Instead you are recommended to use L< Catalyst::Model::Adaptor > or similar to +compose the functionality you need outside of the main application namespace. =cut