X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FUpgrading.pod;h=f74f15e5a91c022c1fb68923079c901fe8be2ecd;hb=bb48c5566ee0170fd913574d2393f381d214f86c;hp=8a9993004c17917ffa6911ff38e5ac5f29970ce7;hpb=ade0097285a43b356dd4fd08b124f0839153de28;p=catagits%2FCatalyst-Runtime.git

diff --git a/lib/Catalyst/Upgrading.pod b/lib/Catalyst/Upgrading.pod
index 8a99930..f74f15e 100644
--- a/lib/Catalyst/Upgrading.pod
+++ b/lib/Catalyst/Upgrading.pod
@@ -1,50 +1,291 @@
+=head1 NAME
+
+Catalyst::Upgrading - Instructions for upgrading to the latest Catalyst
+
+=head1 Upgrading to Catalyst 5.90
+
+The major change is that L<Plack> now replaces most of the subclasses of
+L<Catalyst::Engine>.  If you are using one of the standard subclasses of
+L<Catalyst::Engine> this should be a straightforward upgrade for you. It was
+a design goal for this release to be as backwardly compatible as possible.
+However since L<Plack> is different from L<Catalyst::Engine> it is possible
+that edge case differences exist.  Therefore we recommend care be taken with
+this upgrade and that testing should be greater than would be the case with a
+minor point update.
+
+It is highly recommended that you become familiar with the L<Plack> ecosystem
+and documentation. Being able to take advantage of L<Plack> development and
+middleware is a major bonus to this upgrade. Documentation about how to
+take advantage of L<Plack::Middleware> by writing your own C<< .psgi >> file
+is contained in L<Catalyst::PSGI>.
+
+If you have created a custom subclass of L<Catalyst:Engine> you will need to
+convert it to be a subclass of L<Plack::Handler>.
+
+If you are using the L<Plack> engine, L<Catalyst::Engine::PSGI>, this new
+release supersedes that code.
+
+If you are using a subclass of L<Catalyst::Engine> that is aimed at nonstandard
+or internal / testing uses, such as L<Catalyst::Engine::Embeddable> you should
+still be able to continue using that engine.
+
+Advice for specific subclasses of L<Catalyst::Engine> follows:
+
+=head2 Upgrading the FastCGI Engine
+
+No upgrade needed if your myapp_fastcgi.pl script is already upgraded
+enough to use L<Catalyst::Script::FastCGI>.
+
+=head2 Upgrading the mod_perl / Apache Engines
+
+The engines that are build upon the various iterations of mod_perl,
+L<Catalyst::Engine::Apache::MP13> and
+L<Catalyst::Engine::Apache2::MP20> should be seamless upgrades and will
+work using using L<Plack::Handler::Apache1> or L<Plack::Handler::Apache2>
+as required.  
+
+L<Catalyst::Engine::Apache2::MP19>, is however no longer supported, as Plack
+does not support mod_perl version 1.99
+
+=head2 Upgrading the HTTP Engine
+
+The default development server that comes with the L<Catalyst> distribution
+should continue to work as expected with no changes as long as your C<myapp_server>
+script is upgraded to use L<Catalyst::Script::HTTP>.
+
+=head2 Upgrading the CGI Engine
+
+If you were using L<Catalyst::Engine::CGI> there is no upgrade needed if your
+myapp_cgi.pl script is already upgraded enough to use L<Catalyst::Script::CGI>.
+
+=head2 Upgrading the Preforking Engine
+
+If you were using L<Catalyst::Engine::HTTP::Prefork> then L<Starman>
+is automatically loaded.
+
+If you were customising your server script to pass options to the prefork engine,
+then this is no longer supported. The recommended route to implement this functionality
+is to write a simple .psgi file for your application, then use the L<plackup> utility.
+
+=head2 Upgrading the PSGI Engine
+
+If you were using L<Catalyst::Engine::PSGI> this new release supersedes this
+engine in supporting L<Plack>. By default the Engine is now always L<Plack>.
+As a result, you can stop depending on L<Catalyst::Engine::PSGI> in your
+C<Makefile.PL>. 
+
+Applications that were using L<Catalyst::Engine::PSGI>
+previously should entirely continue to work in this release with no changes.
+
+However, if you have an C<app.psgi> script, then you no longer
+need to specify the PSGI engine.  Instead, the L<Catalyst> application class
+now has a new method C<psgi_app> which returns a L<PSGI> compatible coderef
+which you can wrap in middleware of your choice.
+
+Catalyst will use the .psgi for your application if it is located in the C<home>
+directory of the application
+
+For example, if you were using L<Catalyst::Engine::PSGI> in the past, you will
+have written (or generated) a C<script/myapp.psgi> file similar to this one:
+
+    use Plack::Builder;
+    use MyCatalytApp;
+
+    MyCatalystApp->setup_engine('PSGI');
+
+    builder {
+        enable ... # enable your desired middleware
+        sub { MyCatalystApp->run(@_) };
+    };
+
+Instead, you now say:
+
+    use Plack::Builder;
+    use MyCatalystApp;
+
+    builder {
+        enable ... #enable your desired middleware
+        MyCatalystApp->psgi_app;
+    };
+
+In the simplest case:
+
+    MyCatalystApp->setup_engine('PSGI');
+    my $app = sub { MyCatalystApp->run(@_) }
+
+becomes
+
+    MyCatalystApp->setup_engine('PSGI');
+    my $app = MyCatalystApp->psgi_app(@_);
+
+B<NOT>:
+
+    my $app = sub { MyCatalystApp->psgi_app(@_) };
+    # If you make ^^ this mistake, your app won't work, and will confuse the hell out of you!
+
+You can now move C<< script/myapp.psgi >> to C<< myapp.psgi >> and the built-in
+Catalyst scripts and your test suite will start using your .psgi file.
+
+B<NOTE:> If you rename your .psgi file without these modifications, then any tests run via
+L<Catalyst::Test> will not be compatible with the new release, and will result in
+the development server starting, rather than the expected test running.
+
+=head2 Engines which are known broken
+
+The following engines B<DO NOT> work as of Catalyst version 5.90. The core
+team is extremely happy to work with the developers and/or users of these
+engines to help them port to the new Plack/Engine system, however applications
+which are currently using these engines B<WILL NOT> run without modification
+to the engine code.
+
+=over
+
+=item Catalyst::Engine::Wx
+
+=item Catalyst::Engine::Zeus
+
+=item Catalyst::Engine::JobQueue::POE
+
+=item Catalyst::Engine::XMPP2
+
+=item Catalyst::Engine::SCGI
+
+=back
+
+=head2 Engines with unknown status
+
+The following engines have untested or unknown compatibility.  Reports are
+highly welcomed:
+
+=over
+
+=item Catalyst::Engine::Mojo
+
+=item Catalyst::Engine::Server (Marked as Deprecated)
+
+=item Catalyst::Engine::HTTP::POE (Marked as Deprecated)
+
+=back
+
+=head2 Specifying the engine in the call to ->setup
+
+XXX FIXME
+
+=head2 Plack functionality
+
+See L<Catalyst::PSGI>.
+
+=head2 Tests in 5.89
+
+Tests should generally work the same in Catalyst 5.89, however there are some differences.
+
+Previously, if using L<Catalyst::Test> and doing local requests (against a local server),
+if the application threw an exception then this exception propagated into the test.
+
+This behavior has been removed, and now a 500 response will be returned to the test.
+This change unifies behavior, to make local test requests behave similarly to remote
+requests.
+
 =head1 Upgrading to Catalyst 5.80
 
 Most applications and plugins should run unaltered on Catalyst 5.80.
 
-However as a lot of refactoring work has taken place, and several changes have
+However, a lot of refactoring work has taken place, and several changes have
 been made which could cause incompatibilities. If your application or plugin
-is using deprecated code, or relying on side-effects, then you could have
+is using deprecated code, or relying on side effects, then you could have
 issues upgrading to this release.
 
-Most issues found with pre-existing components have been easy to solve, and a
-complete description of behaviour changes which may cause compatibility issues,
-or warnings which are now emitted is included below to help if you have problems.
+Most issues found with pre-existing components have been easy to
+solve. This document provides a complete description of behavior changes
+which may cause compatibility issues, and of new Catalyst warnings which
+might be unclear.
+
+If you think you have found an upgrade-related issue which is not covered in
+this document, please email the Catalyst list to discuss the problem.
+
+=head1 Moose features
+
+=head2 Application class roles
+
+You can only apply method modifiers after the application's C<< ->setup >>
+method has been called. This means that modifiers will not work with methods
+run during the call to C<< ->setup >>.
+
+See L<Catalyst::Manual::ExtendingCatalyst> for more information about using
+L<Moose> in your applications.
+
+=head2 Controller actions in Moose roles
+
+You can use L<MooseX::MethodAttributes::Role> if you want to declare actions
+inside Moose roles.
+
+=head2 Using Moose in Components
+
+The correct way to use Moose in a component in a both forward and backwards
+compatible way is:
+
+    package TestApp::Controller::Root;
+    use Moose;
+    BEGIN { extends 'Catalyst::Component' }; # Or ::Controller, or whatever
+
+See L<Components which inherit from Moose::Object before Catalyst::Component>.
+
+=head1 Known backwards compatibility breakages
+
+=head2 Applications in a single file
 
-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.
+Applications must be in their own file, and loaded at compile time. This
+issue generally only affects the tests of CPAN distributions. Your
+application will fail if you try to define an application inline in a
+block, and use plugins which supply a C< new > method, then use that
+application latter in tests within the same file.
 
-=head1 Known backwards compatibility breakages.
+This is due to the fact that Catalyst is inlining a new method on your
+application class allowing it to be compatible with Moose. The method
+used to do this changed in 5.80004 to avoid the possibility of reporting
+an 'Unknown Error' if your application failed to compile.
 
 =head2 Issues with Class::C3
 
-Catalyst 5.80 uses L<Algorithm::C3> method dispatch order. This is built into
-perl 5.10, and comes via L<Class::C3> for perl 5.8. This replaces L<NEXT>
-with L<Class::C3::Adopt::NEXT>, forcing all components to resolve methods using
-C3, rather than the unpredictable dispatch order of L<NEXT>.
+Catalyst 5.80 uses the L<Algorithm::C3> method dispatch order. This is
+built into Perl 5.10, and comes via L<Class::C3> for Perl 5.8. This
+replaces L<NEXT> with L<Class::C3::Adopt::NEXT>, forcing all components
+to resolve methods using C3, rather than the unpredictable dispatch
+order of L<NEXT>.
 
-To be able to do this, however, entails that the graph of superclasses for each
-class must be linearizable using the C3 algorithm. Unfortunately, when
-superclasses are being used as mixins, it is easy to get this wrong.
+This issue is characterised by your application failing to start due to an
+error message about having a non-linear @ISA.
+
+The Catalyst plugin most often causing this is
+L<Catalyst::Plugin::Session::Store::FastMmap> - if you are using this
+plugin and see issues, then please upgrade your plugins, as it has been
+fixed. Note that Makefile.PL in the distribution will warn about known
+incompatible components.
+
+This issue can, however, be found in your own application - the only solution is
+to go through each base class of the class the error was reported against, until
+you identify the ones in conflict, and resolve them.
+
+To be able to generate a linear @ISA, the list of superclasses for each
+class must be resolvable using the C3 algorithm. Unfortunately, when
+superclasses are being used as mixins (to add functionality used in your class),
+and with multiple inheritance, it is easy to get this wrong.
 
 Most common is the case of:
 
     package Component1; # Note, this is the common case
     use base qw/Class::Accessor::Fast Class::Data::Inheritable/;
 
-    package Component2; # Accidentally saying it this way round causes fail.
+    package Component2; # Accidentally saying it this way causes a failure
     use base qw/Class::Data::Inheritable Class::Accessor::Fast/;
 
     package GoesBang;
     use base qw/Component1 Component2/;
 
-And the Catalyst plugin most often causing this, is
-L<Catalyst::Plugin::Sesssion::Store::FastMMap> - if you are using this plugin
-and see issues, then please upgrade!
+Any situation like this will cause your application to fail to start.
 
-This can, however, be found in your own application - the only solution is to
-go through each base class of the class the error was reported against, until
-you identify the ones in conflict, and resolve them.
+For additional documentation about this issue, and how to resolve it, see
+L<Class::C3::Adopt::NEXT>.
 
 =head2 Components which inherit from Moose::Object before Catalyst::Component
 
@@ -54,25 +295,10 @@ Moose components which say:
     use Moose;
     extends qw/Moose::Object Catalyst::Component/;
 
-to use the constructor provided by Moose, whilst working (if you do some hacks
+to use the constructor provided by Moose, while working (if you do some hacks
 with the C< BUILDARGS > method), will not work with Catalyst 5.80 as
 C<Catalyst::Component> inherits from C<Moose::Object>, and so C< @ISA > fails
-to linearise.
-
-The fix for this is to not inherit directly from C<Moose::Object>
-yourself. Having components which do not inherit their constructor from
-C<Catalyst::Component> is B<unsupported>, 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.
-
-You will also see this issue if you do the following:
-
-    package TestApp::Controller::Example;
-    use Moose;
-    use base 'Catalyst::Controller';
-
-as C< use base > appends to @ISA.
+to linearize.
 
 The correct way to use Moose in a component in a both forward and backwards
 compatible way is:
@@ -84,17 +310,32 @@ compatible way is:
 Note that the C< extends > declaration needs to occur in a begin block for
 L<attributes> to operate correctly.
 
-You also don't get the L<Moose::Object> constructor, and therefore attribute 
-initialization will not work as normally expected. If you want to use Moose 
+This way you do not inherit directly from C<Moose::Object>
+yourself. Having components which do not inherit their constructor from
+C<Catalyst::Component> is B<unsupported>, 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, and deal
+with it appropriately.
+
+You also don't get the L<Moose::Object> constructor, and therefore attribute
+initialization will not work as normally expected. If you want to use Moose
 attributes, then they need to be made lazy to correctly initialize.
 
 Note that this only applies if your component needs to maintain component
 backwards compatibility for Catalyst versions before 5.71001 - in 5.71001
 attributes work as expected, and the BUILD method is called normally
-(although BUILDARGS is not). 
+(although BUILDARGS is not).
 
 If you depend on Catalyst 5.8, then B<all> Moose features work as expected.
 
+You will also see this issue if you do the following:
+
+    package TestApp::Controller::Example;
+    use Moose;
+    use base 'Catalyst::Controller';
+
+as C< use base > appends to @ISA.
+
 =head3 use Moose in MyApp
 
 Similar to the above, this will also fail:
@@ -107,11 +348,15 @@ Similar to the above, this will also fail:
     __PACKAGE__->setup;
 
 If you need to use Moose in your application class (e.g. for method modifiers
-etc) then the correct technique is:
+etc.) then the correct technique is:
 
     package MyApp;
     use Moose;
+    use Catalyst;
+
     extends 'Catalyst';
+
+    __PACKAGE__->config( name => 'MyApp' );
     __PACKAGE__->setup(qw/
         ConfigLoader
     /);
@@ -131,7 +376,7 @@ to use L<Sub::Name> to name the subroutine. Example:
     my $full_method_name = join('::',$package_name, $method_name);
     *$full_method_name = subname $full_method_name, sub { ... };
 
-Additionally, you can take advantage of Catalysts use of L<Class::MOP> and
+Additionally, you can take advantage of Catalyst's use of L<Class::MOP> and
 install the closure using the appropriate metaclass. Example:
 
     use Class::MOP;
@@ -140,7 +385,7 @@ install the closure using the appropriate metaclass. Example:
 
 =head2 Hooking into application setup
 
-To execute code during application startup the following snippet in MyApp.pm
+To execute code during application start-up, the following snippet in MyApp.pm
 used to work:
 
     sub setup {
@@ -149,14 +394,14 @@ used to work:
         ... # things to do after the actual setup
     }
 
-With Catalyst 5.80 this won't work anymore. Due to the fact that Catalyst is
-no longer using NEXT.pm for method resolution, this no longer works. The
-functionality was only ever originally operational as L<NEXT> remembers what
-methods have already been called, and will not call them again.
+With Catalyst 5.80 this won't work anymore, because Catalyst no longer
+uses NEXT.pm for method resolution. The functionality was only ever
+originally operational as L<NEXT> remembers what methods have already
+been called, and will not call them again.
 
 Using this now causes infinite recursion between MyApp::setup and
 Catalyst::setup, due to other backwards compatibility issues related to how
-plugin setup works. Moose method modifiers like C<< before|after|around 'setup
+plugin setup works. Moose method modifiers like C<< before|after|around setup
 => sub { ... }; >> also will not operate correctly on the setup method.
 
 The right way to do it is this:
@@ -170,13 +415,13 @@ The setup_finalize hook was introduced as a way to avoid this issue.
 =head2 Components with a new method which returns false
 
 Previously, if you had a component which inherited from Catalyst::COMPONENT,
-but overrode the new method to return false, then your class' configuration
+but overrode the new method to return false, then your class's 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. Implementing your own
-C< new > method in components is B<highly> discouraged, instead, you should
-inherit the new method from Catalyst::Component, and use Mooses BUILD
+This behavior makes no sense, and so has been removed. Implementing your own
+C< new > method in components is B<highly> discouraged. Instead, you should
+inherit the new method from Catalyst::Component, and use Moose's BUILD
 functionality and/or Moose attributes to perform any construction work
 necessary for your class.
 
@@ -190,10 +435,10 @@ inside Moose.
 Previously, writing to a class data accessor would copy the accessor method
 down into your package.
 
-This behaviour has been removed. Whilst the class data is still stored
+This behavior has been removed. While the class data is still stored
 per-class, it is stored on the metaclass of the class defining the accessor.
 
-Therefore anything relying on the side-effect of the accessor being copied down
+Therefore anything relying on the side effect of the accessor being copied down
 will be broken.
 
 The following test demonstrates the problem:
@@ -211,25 +456,25 @@ The following test demonstrates the problem:
 
     BaseClass->foo('base class');
     Child->foo('sub class');
-    
+
     use Test::More;
     isnt(BaseClass->can('foo'), Child->can('foo'));
 
-=head2 Extending Catalyst::Request or other classes in an ad-hoc manor using mk_accessors
+=head2 Extending Catalyst::Request or other classes in an ad hoc manner 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 whose
-behaviour they would like to change, rather than globally polluting the
+This is no longer supported - users should make a subclass of the class whose
+behavior they would like to change, rather than globally polluting the
 Catalyst objects.
 
 =head2 Confused multiple inheritance with Catalyst::Component::COMPONENT
 
-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 AND makes no sense with C3 method dispatch order), and is therefore
-no longer supported.
+Previously, Catalyst's COMPONENT method would delegate to the method on
+the right hand side, which could then delegate back again with
+NEXT. This is poor practice, and in addition, makes no sense with C3
+method dispatch order, and is therefore no longer supported.
 
 If a COMPONENT method is detected in the inheritance hierarchy to the right
 hand side of Catalyst::Component::COMPONENT, then the following warning
@@ -238,21 +483,58 @@ message will be emitted:
     There is a COMPONENT method resolving after Catalyst::Component
     in ${next_package}.
 
-The correct fix is to re-arrange your class' inheritance hierarchy so that the
+The correct fix is to re-arrange your class's inheritance hierarchy so that the
 COMPONENT method you would like to inherit is the first (left-hand most)
 COMPONENT method in your @ISA.
 
 =head1 WARNINGS
 
+=head2 Actions in your application class
+
+Having actions in your application class will now emit a warning at application
+startup as this is deprecated. It is highly recommended that these actions are moved
+into a MyApp::Controller::Root (as demonstrated by the scaffold application
+generated by catalyst.pl). 
+
+This warning, also affects tests. You should move actions in your test,
+creating a myTest::Controller::Root, like the following example:
+
+    package MyTest::Controller::Root;
+
+    use strict;
+    use warnings;
+
+    use parent 'Catalyst::Controller';
+
+    __PACKAGE__->config(namespace => '');
+
+    sub action : Local {
+        my ( $self, $c ) = @_;
+        $c->do_something; 
+    }
+
+    1;
+
+=head2 ::[MVC]:: naming scheme
+
+Having packages called MyApp::[MVC]::XX is deprecated and can no longer be generated
+by catalyst.pl
+
+This is still supported, but it is recommended that you rename your application
+components to Model/View/Controller.
+
+A warning will be issued at application startup if the ::[MVC]:: naming scheme is
+in use.
+
 =head2 Catalyst::Base
 
-Any code using L<Catalyst::Base> will now warn, and this module will be removed
-in a future release.
+Any code using L<Catalyst::Base> will now emit a warning; this
+module will be removed in a future release.
 
 =head2 Methods in Catalyst::Dispatcher
 
-The following methods in Catalyst::Dispatcher are both an implementation
-detail, which may change in the 5.8X release series, and therefore their use
+The following methods in Catalyst::Dispatcher are implementation
+details, which may change in the 5.8X release series, and therefore their use
 is highly deprecated.
 
 =over
@@ -278,12 +560,12 @@ The first time one of these methods is called, a warning will be emitted:
 
 You should B<NEVER> be calling any of these methods from application code.
 
-Plugins authors and maintainers whose plugins currently call these methods
+Plugin authors and maintainers whose plugins currently call these methods
 should change to using the public API, or, if you do not feel the public API
-adequately supports your use-case, please email the development list to
+adequately supports your use case, please email the development list to
 discuss what API features you need so that you can be appropriately supported.
 
-=head2 Class naming to packages defined does not correspond.
+=head2 Class files with names that don't correspond to the packages they define
 
 In this version of Catalyst, if a component is loaded from disk, but no
 symbols are defined in that component's name space after it is loaded, this
@@ -291,19 +573,19 @@ warning will be issued:
 
     require $class was successful but the package is not defined.
 
-This is to protect against confusing bugs caused by mis-typing package names,
+This is to protect against confusing bugs caused by mistyping package names,
 and will become a fatal error in a future version.
 
 Please note that 'inner packages' (via L<Devel::InnerPackage>) are still fully
-supported, this warning is only issued when component file naming does not map
+supported; this warning is only issued when component file naming does not map
 to B<any> of the packages defined within that component.
 
 =head2 $c->plugin method
 
-Calling the plugin method is deprecated, and calling it at runtime is B<highly
+Calling the plugin method is deprecated, and calling it at run time is B<highly
 deprecated>.
 
-Instead you are recommended to use L< Catalyst::Model::Adaptor > or similar to
+Instead you are recommended to use L<Catalyst::Model::Adaptor> or similar to
 compose the functionality you need outside of the main application name space.
 
 Calling the plugin method will not be supported past Catalyst 5.81.