X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=catagits%2FCatalyst-Manual.git;a=blobdiff_plain;f=lib%2FCatalyst%2FManual%2FIntro.pod;h=e9ba5b18afce7b14e6faa5356a981076a548fa0c;hp=f0895f503b893e1754b9b7cab816a3959ee60bb6;hb=f577e42d6082c6b034295995286d248e57e290e0;hpb=08cb655fc7727601466be297a251b56a4fed6e34 diff --git a/lib/Catalyst/Manual/Intro.pod b/lib/Catalyst/Manual/Intro.pod index f0895f5..e9ba5b1 100644 --- a/lib/Catalyst/Manual/Intro.pod +++ b/lib/Catalyst/Manual/Intro.pod @@ -23,7 +23,7 @@ possible to do things in a different way. Other web frameworks are I simpler to use, but achieve this by locking the programmer into a single set of tools. Catalyst's emphasis on flexibility means that you have to think more to use it. We view this as a feature. For -example, this leads to Catalyst being more suited to system integration +example, this leads to Catalyst being better suited to system integration tasks than other web frameworks. =head3 MVC @@ -53,7 +53,7 @@ L, L... =item * B Control the whole request phase, check parameters, dispatch actions, flow -control. Catalyst itself! +control. This is the meat of where Catalyst works. =back @@ -104,7 +104,7 @@ example: Now http://localhost:3000/hello prints "Hello World!". -Note that actions with the C< :Global > attribute are equivalent to +Note that actions with the C< :Local > attribute are equivalent to using a C<:Path('action_name') > attribute, so our action could be equivalently: @@ -357,7 +357,7 @@ Now we can create a DBIC::Schema model for this database. script/myapp_create.pl model MyModel DBIC::Schema MySchema create=static 'dbi:SQLite:/tmp/myapp.db' -L can automaticall load table layouts and +L can automatically load table layouts and relationships, and convert them into a static schema definition C, which you can edit later. @@ -759,7 +759,7 @@ will look at the URL it is processing, and the actions that it has found, and automatically call the actions it finds that match the circumstances of the request. -The URL (for example http://localhost.3000/foo/bar) consists of two +The URL (for example http://localhost:3000/foo/bar) consists of two parts, the base, describing how to connect to the server (http://localhost:3000/ in this example) and the path, which the server uses to decide what to return (foo/bar). Please note that the @@ -784,7 +784,7 @@ of Catalyst component class names. =item * B -Note that __PACKAGE__->config->{namespace} can be used to override the +Note that I<< __PACKAGE__->config->(namespace => ... ) >> can be used to override the current namespace when matching. So: package MyApp::Controller::Example; @@ -792,7 +792,7 @@ current namespace when matching. So: would normally use 'example' as its namespace for matching, but if this is specially overridden with - __PACKAGE__->config->{namespace}='thing'; + __PACKAGE__->config( namespace => 'thing' ); it matches using the namespace 'thing' instead. @@ -804,25 +804,29 @@ application (e.g. http://localhost:3000/ ): package MyApp::Controller::Root; use base 'Catalyst::Controller'; + # Sets the actions in this controller to be registered with no prefix # so they function identically to actions created in MyApp.pm - __PACKAGE__->config->{namespace} = ''; + + __PACKAGE__->config( namespace => ''); + sub default : Path { my ( $self, $context ) = @_; $context->response->status(404); $context->response->body('404 not found'); } + 1; The code - __PACKAGE__->config->{namespace} = ''; + __PACKAGE__->config( namespace => '' ); makes the controller act as if its namespace is empty. As you'll see -below, an empty namespace makes many of the URL-matching attributes, -such as :Path, :Local and :Global matches, match at the start of the -URL path. +below, an empty namespace makes many of the URL-matching attributes, such +as :Path and :Local match at the start of the URL path (i.e. the +application root). =back @@ -847,22 +851,33 @@ of the path is passed as arguments. Matches any URL beginning with> http://localhost:3000/my/controller/foo. The namespace and subroutine name together determine the path. -=item * Namespace-level (C<:Global>) +=item * Root-level (C<:Global>) package MyApp::Controller::Foo; - sub foo : Global { } + + sub bar : Global { + my ($self, $c) = @_; + $c->res->body( + $c->res->body('sub bar in Controller::Foo triggered on a request for ' + . $c->req->uri)); + } + +1; Matches http://localhost:3000/foo - that is, the action is mapped directly to the controller namespace, ignoring the function name. -C<:Global> is equivalent C<:Local> one level higher in -the namespace. - - package MyApp::Controller::Root; - __PACKAGE__->config->{namespace}=''; - sub foo : Local { } +C<:Global> always matches from the application root: it is simply +shorthandfor C<:Path('/methodname')>. C<:Local> is shorthand for +C<:Path('methodname')>, which takes the controller namespace as described +above. -Use whichever makes the most sense for your application. +Usage of the C handler is rare in all but very old Catalyst +applications (e.g. before Catalyst 5.7). The use cases where C +used to make sense are now largely replaced by the C dispatch +type, or by empty C declarations on an controller action. C +is still included in Catalyst for backwards compatibility, although +legitimate use-cases for it may still exist (but nobody can. =item * Changing handler behaviour: eating arguments (C<:Args>) @@ -887,7 +902,9 @@ C<:Args(0)> means that no arguments are taken. Thus, the URL and path must match precisely. No :Args at all means that B of arguments are taken. Thus, any -URL that B the controller's path will match. +URL that B the controller's path will match. Obviously, this means +you cannot chain from an action that does not specify args, as the next action +in the chain will be swallowed as an arg to the first! =item * Literal match (C<:Path>) @@ -1096,7 +1113,7 @@ turn. sub auto : Private { } C, however, doesn't override like this: providing they exist, -C, C and +C, C and C would be called in turn. Here are some examples of the order in which the various built-ins @@ -1262,9 +1279,9 @@ be reset. # now $c->req->args is back to what it was before } - sub check_message : Private { - my ( $self, $c ) = @_; - my $first_argument = $c->req->args->[0]; # now = 'test1' + sub check_message : Action { + my ( $self, $c, $first_argument ) = @_; + my $also_first_argument = $c->req->args->[0]; # now = 'test1' # do something... } @@ -1276,14 +1293,11 @@ you will have to refer to the method by absolute path. $c->forward('/my/controller/action'); $c->forward('/default'); # calls default in main application -Here are some examples of how to forward to classes and methods. - - # FIXME - Forwarding to a model is unusual, a better example would show - # forwarding to render in TT which is useful for drawing sub-parts of pages.. +You can also forward to classes and methods. sub hello : Global { my ( $self, $c ) = @_; - $c->forward(qw/MyApp::Model::Hello say_hello/); + $c->forward(qw/MyApp::View:Hello say_hello/); } sub bye : Global { @@ -1291,7 +1305,7 @@ Here are some examples of how to forward to classes and methods. $c->forward('MyApp::Model::Hello'); # no method: will try 'process' } - package MyApp::Model::Hello; + package MyApp::View::Hello; sub say_hello { my ( $self, $c ) = @_; @@ -1303,6 +1317,28 @@ Here are some examples of how to forward to classes and methods. $c->res->body('Goodbye World!'); } +This mechanism is used by L to forward +to the C method in a view class. + +It should be noted that whilst forward is useful, it is not the only way +of calling other code in Catalyst. Forward just gives you stats in the debug +screen, wraps the code you're calling in an exception handler and localises +C<< $c->request->args >>. + +If you don't want or need these features then it's perfectly acceptable +(and faster) to do something like this: + + sub hello : Global { + my ( $self, $c ) = @_; + $c->stash->{message} = 'Hello World!'; + $self->check_message( $c, 'test1' ); + } + + sub check_message { + my ( $self, $c, $first_argument ) = @_; + # do something... + } + Note that C returns to the calling action and continues processing after the action finishes. If you want all further processing in the calling action to stop, use C instead, which will execute @@ -1310,7 +1346,6 @@ the Ced action and not return to the calling sub. In both cases, Catalyst will automatically try to call process() if you omit the method. - =head3 Testing Catalyst has a built-in http server for testing or local