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1 | =head1 NAME |
2 | |
3 | Catalyst::Manual::ExtendingCatalyst - Extending The Framework |
4 | |
5 | =head1 DESCRIPTION |
6 | |
7 | This document will provide you with access points, techniques and best |
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8 | practices to extend the L<Catalyst> framework, or to find more elegant |
9 | ways to abstract and use your own code. |
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10 | |
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11 | The design of Catalyst is such that the framework itself should not |
12 | get in your way. There are many entry points to alter or extend |
13 | Catalyst's behaviour, and this can be confusing. This document is |
14 | written to help you understand the possibilities, current practices |
15 | and their consequences. |
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16 | |
17 | Please read the L<BEST PRACTICES> section before deciding on a design, |
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18 | especially if you plan to release your code to CPAN. The Catalyst |
19 | developer and user communities, which B<you are part of>, will benefit |
20 | most if we all work together and coordinate. |
21 | |
22 | If you are unsure on an implementation or have an idea you would like |
23 | to have RFC'ed, it surely is a good idea to send your questions and |
24 | suggestions to the Catalyst mailing list (See L<Catalyst/SUPPORT>) |
25 | and/or come to the C<#catalyst> channel on the C<irc.perl.org> |
26 | network. You might also want to refer to those places for research to |
27 | see if a module doing what you're trying to implement already |
28 | exists. This might give you a solution to your problem or a basis for |
29 | starting. |
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30 | |
31 | =head1 BEST PRACTICES |
32 | |
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33 | During Catalyst's early days, it was common to write plugins to |
34 | provide functionality application wide. Since then, Catalyst has |
35 | become a lot more flexible and powerful. It soon became a best |
36 | practice to use some other form of abstraction or interface, to keep |
37 | the scope of its influence as close as possible to where it belongs. |
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38 | |
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39 | For those in a hurry, here's a quick checklist of some fundamental |
40 | points. If you are going to read the whole thing anyway, you can jump |
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41 | forward to L</Namespaces>. |
42 | |
43 | =head2 Quick Checklist |
44 | |
45 | =over |
46 | |
47 | =item Use the C<CatalystX::*> namespace if you can! |
48 | |
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49 | If your extension isn't a Model, View, Controller, Plugin, or Engine, |
50 | it's best to leave it out of the C<Catalyst::> namespace. Use |
51 | <CatalystX::> instead. |
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52 | |
53 | =item Don't make it a plugin unless you have to! |
54 | |
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55 | A plugin should be careful since it's overriding Catalyst internals. |
56 | If your plugin doesn't really need to muck with the internals, make it a |
57 | base Controller or Model. |
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58 | |
59 | =item There's a community. Use it! |
60 | |
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61 | There are many experienced developers in the Catalyst community, |
62 | there's always the IRC channel and the mailing list to discuss things. |
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63 | |
64 | =item Add tests and documentation! |
65 | |
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66 | This gives a stable basis for contribution, and even more importantly, |
67 | builds trust. The easiest way is a test application. See |
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68 | L<Catalyst::Manual::Tutorial::Testing> for more information. |
69 | |
70 | =back |
71 | |
72 | =head2 Namespaces |
73 | |
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74 | While some core extensions (engines, plugins, etc.) have to be placed |
75 | in the C<Catalyst::*> namespace, the Catalyst core would like to ask |
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76 | developers to use the C<CatalystX::*> namespace if possible. |
77 | |
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78 | When you try to put a base class for a C<Model>, C<View> or |
79 | C<Controller> directly under your C<MyApp> directory as, for example, |
80 | C<MyApp::Controller::Foo>, you will have the problem that Catalyst |
81 | will try to load that base class as a component of your |
82 | application. The solution is simple: Use another namespace. Common |
83 | ones are C<MyApp::Base::Controller::*> or C<MyApp::ControllerBase::*> |
84 | as examples. |
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85 | |
86 | =head2 Can it be a simple module? |
87 | |
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88 | Sometimes you want to use functionality in your application that |
89 | doesn't require the framework at all. Remember that Catalyst is just |
90 | Perl and you always can just C<use> a module. If you have application |
91 | specific code that doesn't need the framework, there is no problem in |
92 | putting it in your C<MyApp::*> namespace. Just don't put it in |
93 | C<Model>, C<Controller> or C<View>, because that would make Catalyst |
94 | try to load them as components. |
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95 | |
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96 | Writing a generic component that only works with Catalyst is wasteful |
97 | of your time. Try writing a plain perl module, and then a small bit |
98 | of glue that integrates it with Catalyst. See |
99 | L<Catalyst::Model::DBIC::Schema|Catalyst::Model::DBIC::Schema> for a |
100 | module that takes the approach. The advantage here is that your |
101 | "Catalyst" DBIC schema works perfectly outside of Catalyst, making |
102 | testing (and command-line scripts) a breeze. The actual Catalyst |
103 | Model is just a few lines of glue that makes working with the schema |
104 | convenient. |
105 | |
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106 | =head2 Inheritance and overriding methods |
107 | |
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108 | While Catalyst itself is still based on L<NEXT> (for multiple |
109 | inheritance), extension developers are encouraged to use L<Class::C3>, |
110 | which is what Catalyst will be switching to in some point in the |
111 | future. |
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112 | |
113 | When overriding a method, keep in mind that some day additionally |
114 | arguments may be provided to the method, if the last parameter is not |
115 | a flat list. It is thus better to override a method by shifting the |
116 | invocant off of C<@_> and assign the rest of the used arguments, so |
117 | you can pass your complete arguments to the original method via C<@_>: |
118 | |
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119 | use Class::C3; ... |
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120 | |
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121 | sub foo { my $self = shift; |
122 | my ($bar, $baz) = @_; # ... return |
123 | $self->next::method(@_); } |
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124 | |
125 | If you would do the common |
126 | |
127 | my ($self, $foo, $bar) = @_; |
128 | |
129 | you'd have to use a much uglier construct to ensure that all arguments |
130 | will be passed along and the method is future proof: |
131 | |
132 | $self->next::method(@_[ 1 .. $#_ ]); |
133 | |
134 | =head2 Tests and documentation |
135 | |
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136 | When you release your module to the CPAN, proper documentation and at |
137 | least a basic test suite (which means more than pod or even just |
138 | C<use_ok>, sorry) gives people a good base to contribute to the |
139 | module. It also shows that you care for your users. If you would like |
140 | your module to become a recommended addition, these things will prove |
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141 | invaluable. |
142 | |
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143 | If you're just getting started, try using |
144 | L<CatalystX::Starter|CatalystX::Starter> to generate some example |
145 | tests for your module. |
146 | |
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147 | =head2 Maintenance |
148 | |
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149 | In planning to release a module to the community (Catalyst or CPAN and |
150 | Perl), you should consider if you have the resources to keep it up to |
151 | date, including fixing bugs and accepting contributions. |
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152 | |
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153 | If you're not sure about this, you can always ask in the proper |
154 | Catalyst or Perl channels if someone else might be interested in the |
155 | project, and would jump in as co-maintainer. |
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156 | |
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157 | A public repository can further ease interaction with the |
158 | community. Even read only access enables people to provide you with |
159 | patches to your current development version. subversion, SVN and SVK, |
160 | are broadly preferred in the Catalyst community. |
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161 | |
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162 | If you're developing a Catalyst extension, please consider asking the |
163 | core team for space in Catalyst's own subversion repository. You can |
164 | get in touch about this via IRC or the Catalyst developers mailing |
165 | list. |
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166 | |
167 | =head2 The context object |
168 | |
169 | Sometimes you want to get a hold of the context object in a component |
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170 | that was created on startup time, where no context existed yet. Often |
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171 | this is about the model reading something out of the stash or other |
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172 | context information (current language, for example). |
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173 | |
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174 | If you use the context object in your component you have tied it to an |
175 | existing request. This means that you might get into problems when |
176 | you try to use the component (e.g. the model - the most common case) |
177 | outside of Catalyst, for example in cronjobs. |
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178 | |
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179 | A stable solution to this problem is to design the Catalyst model |
180 | separately from the underlying model logic. Let's take |
181 | L<Catalyst::Model::DBIC::Schema> as an example. You can create a |
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182 | schema outside of Catalyst that knows nothing about the web. This kind |
183 | of design ensures encapsulation and makes development and maintenance |
184 | a whole lot easier. The you use the aforementioned model to tie your |
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185 | schema to your application. This gives you a C<MyApp::DBIC> (the name |
186 | is of course just an example) model as well as |
187 | C<MyApp::DBIC::TableName> models to access your result sources |
188 | directly. |
189 | |
190 | By creating such a thin layer between the actual model and the |
191 | Catalyst application, the schema itself is not at all tied to any |
192 | application and the layer in-between can access the model's API using |
193 | information from the context object. |
194 | |
195 | A Catalyst component accesses the context object at request time with |
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196 | L<Catalyst::Component/"ACCEPT_CONTEXT($c, @args)">. |
197 | |
198 | =head1 CONFIGURATION |
199 | |
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200 | The application has to interact with the extension with some |
201 | configuration. There is of course again more than one way to do it. |
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202 | |
203 | =head2 Attributes |
204 | |
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205 | You can specify any valid Perl attribute on Catalyst actions you like. |
206 | (See L<attributes/"Syntax of Attribute Lists"> for a description of |
207 | what is valid.) These will be available on the C<Catalyst::Action> |
208 | instance via its C<attributes> accessor. To give an example, this |
209 | action: |
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210 | |
211 | sub foo : Local Bar('Baz') { |
212 | my ($self, $c) = @_; |
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213 | my $attributes = |
214 | $self->action_for('foo')->attributes; |
215 | $c->res->body($attributes->{Bar}[0] ); |
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216 | } |
217 | |
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218 | will set the response body to C<Baz>. The values always come in an |
219 | array reference. As you can see, you can use attributes to configure |
220 | your actions. You can specify or alter these attributes via |
221 | L</"Component Configuration">, or even react on them as soon as |
222 | Catalyst encounters them by providing your own L<component base |
223 | class|/"Component Base Classes">. |
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224 | |
225 | =head2 Creating custom accessors |
226 | |
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227 | L<Catalyst::Component> uses L<Class::Accessor::Fast> for accessor |
228 | creation. Please refer to the modules documentation for usage |
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229 | information. |
230 | |
231 | =head2 Component configuration |
232 | |
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233 | At creation time, the class configuration of your component (the one |
234 | available via C<$self-E<gt>config>) will be merged with possible |
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235 | configuration settings from the applications configuration (either |
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236 | directly or via config file). This is then stored in the controller |
237 | object's hash reference. So, if you read possible configurations like: |
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238 | |
239 | my $model_name = $controller->{model_name}; |
240 | |
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241 | you will get the right value. The C<config> accessor always only |
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242 | contains the original class configuration and must not be used for |
243 | component configuration. |
244 | |
245 | You are advised to create accessors on your component class for your |
246 | configuration values. This is good practice and makes it easier to |
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247 | capture configuration key typos. You can do this with the |
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248 | C<mk_ro_accessors> method provided to L<Catalyst::Component> via |
249 | L<Class::Accessor::Fast>: |
250 | |
251 | use base 'Catalyst::Controller'; |
252 | __PACKAGE__->mk_ro_accessors('model_name'); |
253 | ... |
254 | my $model_name = $controller->model_name; |
255 | |
256 | =head1 IMPLEMENTATION |
257 | |
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258 | This part contains the technical details of various implementation |
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259 | methods. Please read the L</"BEST PRACTICES"> before you start your |
260 | implementation, if you haven't already. |
261 | |
262 | =head2 Action classes |
263 | |
264 | Usually, your action objects are of the class L<Catalyst::Action>. |
265 | You can override this with the C<ActionClass> attribute to influence |
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266 | execution and/or dispatching of the action. A widely used example of |
267 | this is L<Catalyst::Action::RenderView>, which is used in every newly |
268 | created Catalyst application in your root controller: |
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269 | |
270 | sub end : ActionClass('RenderView') { } |
271 | |
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272 | Usually, you want to override the C<execute> and/or the C<match> |
273 | method. The execute method of the action will naturally call the |
274 | methods code. You can surround this by overriding the method in a |
275 | subclass: |
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276 | |
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277 | package Catalyst::Action::MyFoo; use strict; |
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278 | |
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279 | use Class::C3; use base 'Catalyst::Action'; |
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280 | |
281 | sub execute { |
282 | my $self = shift; |
283 | my ($controller, $c, @args) = @_; |
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284 | # put your 'before' code here |
285 | my $r = $self->next::method(@_); |
286 | # put your 'after' code here |
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287 | return $r; |
288 | } |
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289 | 1; |
290 | |
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291 | We are using L<Class::C3> to re-dispatch to the original C<execute> method |
292 | in the L<Catalyst::Action> class. |
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293 | |
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294 | The Catalyst dispatcher handles an incoming request and, depending |
295 | upon the dispatch type, will call the appropriate target or chain. |
296 | From time to time it asks the actions themselves, or through the |
297 | controller, if they would match the current request. That's what the |
298 | C<match> method does. So by overriding this, you can change on what |
299 | the action will match and add new matching criteria. |
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300 | |
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301 | For example, the action class below will make the action only match on |
302 | Mondays: |
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303 | |
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304 | package Catalyst::Action::OnlyMondays; use strict; |
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305 | |
306 | use Class::C3; |
307 | use base 'Catalyst::Action'; |
308 | |
309 | sub match { |
310 | my $self = shift; |
311 | return 0 if ( localtime(time) )[6] == 1; |
312 | return $self->next::method(@_); |
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313 | } |
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314 | 1; |
315 | |
316 | And this is how we'd use it: |
317 | |
318 | sub foo: Local ActionClass('OnlyMondays') { |
319 | my ($self, $c) = @_; |
320 | $c->res->body('I feel motivated!'); |
321 | } |
322 | |
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323 | If you are using action classes often or have some specific base |
324 | classes that you want to specify more conveniently, you can implement |
325 | a component base class providing an attribute handler. |
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326 | |
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327 | For further information on action classes, please refer to |
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328 | L<Catalyst::Action> and L<Catalyst::Manual::Actions>. |
329 | |
330 | =head2 Component base classes |
331 | |
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332 | Many L<Catalyst::Plugin> that were written in Catalyst's early days |
333 | should really have been just controller base classes. With such a |
334 | class, you could provide functionality scoped to a single controller, |
335 | not polluting the global namespace in the context object. |
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336 | |
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337 | You can provide regular Perl methods in a base class as well as |
338 | actions which will be inherited to the subclass. Please refer to |
339 | L</Controllers> for an example of this. |
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340 | |
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341 | You can introduce your own attributes by specifying a handler method |
342 | in the controller base. For example, to use a C<FullClass> attribute |
343 | to specify a fully qualified action class name, you could use the |
344 | following implementation. Note, however, that this functionality is |
345 | already provided via the C<+> prefix for action classes. A simple |
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346 | |
347 | sub foo : Local ActionClass('+MyApp::Action::Bar') { ... } |
348 | |
349 | will use C<MyApp::Action::Bar> as action class. |
350 | |
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351 | package MyApp::Base::Controller::FullClass; use strict; use base |
352 | 'Catalyst::Controller'; |
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353 | |
354 | sub _parse_FullClass_attr { |
355 | my ($self, $app_class, $action_name, $value, $attrs) = @_; |
356 | return( ActionClass => $value ); |
357 | } |
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358 | 1; |
359 | |
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360 | Note that the full line of arguments is only provided for completeness |
361 | sake. We could use this attribute in a subclass like any other |
362 | Catalyst attribute: |
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363 | |
364 | package MyApp::Controller::Foo; |
365 | use strict; |
366 | use base 'MyApp::Base::Controller::FullClass'; |
367 | |
368 | sub foo : Local FullClass('MyApp::Action::Bar') { ... } |
369 | |
370 | 1; |
371 | |
372 | =head2 Controllers |
373 | |
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374 | Many things can happen in controllers, and it often improves |
375 | maintainability to abstract some of the code out into reusable base |
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376 | classes. |
377 | |
378 | You can provide usual Perl methods that will be available via your |
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379 | controller object, or you can even define Catalyst actions which will |
380 | be inherited by the subclasses. Consider this controller base class: |
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381 | |
382 | package MyApp::Base::Controller::ModelBase; |
383 | use strict; |
384 | use base 'Catalyst::Controller'; |
385 | |
386 | sub list : Chained('base') PathPart('') Args(0) { |
387 | my ($self, $c) = @_; |
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388 | my $model = $c->model( $self->{model_name} ); |
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389 | my $condition = $self->{model_search_condition} || {}; |
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390 | my $attrs = $self->{model_search_attrs} || {}; |
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391 | $c->stash(rs => $model->search($condition, $attrs); |
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392 | } |
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393 | |
394 | sub load : Chained('base') PathPart('') CaptureArgs(1) { |
395 | my ($self, $c, $id) = @_; |
396 | my $model = $c->model( $self->{model_name} ); |
397 | $c->stash(row => $model->find($id)); |
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398 | } |
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399 | 1; |
400 | |
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401 | This example implements two simple actions. The C<list> action chains |
402 | to a (currently non-existent) C<base> action and puts a result-set |
403 | into the stash taking a configured C<model_name> as well as a search |
404 | condition and attributes. This action is a |
405 | L<chained|Catalyst::DispatchType::Chained> endpoint. The other action, |
406 | called C< load > is a chain midpoint that takes one argument. It takes |
407 | the value as an ID and loads the row from the configured model. Please |
408 | not that the above code is simplified for clarity. It misses error |
409 | handling, input validation, and probably other things. |
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410 | |
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411 | The class above is not very useful on its own, but we can combine it |
412 | with some custom actions by sub-classing it: |
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413 | |
414 | package MyApp::Controller::Foo; |
415 | use strict; |
416 | use base 'MyApp::Base::Controller::ModelBase'; |
417 | |
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418 | __PACKAGE__->config( model_name => 'DB::Foo', |
419 | model_search_condition=> { is_active => 1 }, |
420 | model_search_attrs => { order_by => 'name' }, |
421 | ); |
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422 | |
423 | sub base : Chained PathPart('foo') CaptureArgs(0) { } |
424 | |
425 | sub view : Chained('load') Args(0) { |
426 | my ($self, $c) = @_; |
427 | my $row = $c->stash->{row}; |
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428 | $c->res->body(join ': ', $row->name, |
429 | $row->description); } |
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430 | 1; |
431 | |
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432 | This class uses the formerly created controller as a base |
433 | class. First, we see the configurations that were used in the parent |
434 | class. Next comes the C<base> action, where everything chains off of. |
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435 | |
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436 | Note that inherited actions act like they were declared in your |
437 | controller itself. You can therefor call them just by their name in |
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438 | C<forward>s, C<detaches> and C<Chained(..)> specifications. This is an |
439 | important part of what makes this technique so useful. |
440 | |
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441 | The new C<view> action ties itself to the C<load> action specified in |
442 | the base class and outputs the loaded row's C<name> and C<description> |
443 | columns. The controller C<MyApp::Controller::Foo> now has these |
444 | publicly available paths: |
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445 | |
446 | =over |
447 | |
448 | =item /foo |
449 | |
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450 | Will call the controller's C<base>, then the base classes C<list> |
451 | action. |
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452 | |
453 | =item /foo/$id/view |
454 | |
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455 | First, the controller's C<base> will be called, then it will C<load> |
456 | the row with the corresponding C<$id>. After that, C<view> will |
457 | display some fields out of the object. |
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458 | |
459 | =back |
460 | |
461 | =head2 Models and Views |
462 | |
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463 | If the functionality you'd like to add is really a data-set that you |
464 | want to manipulate, for example internal document types, images, |
465 | files, it might be better suited as a model. |
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466 | |
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467 | The same applies for views. If your code handles representation or |
468 | deals with the applications interface and should be universally |
469 | available, it could be a perfect candidate for a view. |
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470 | |
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471 | Please implement a C<process> method in your views. This method will |
472 | be called by Catalyst if it is asked to forward to a component without |
473 | a specified action. Note that C<process> is B<not a Catalyst action> |
474 | but a simple Perl method. |
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475 | |
476 | You are also encouraged to implement a C<render> method corresponding |
477 | with the one in L<Catalyst::View::TT>. This has proven invaluable, |
478 | because people can use your view for much more fine-grained content |
479 | generation. |
480 | |
481 | Here is some example code for a fictional view: |
482 | |
483 | package CatalystX::View::MyView; |
484 | use strict; |
485 | use base 'Catalyst::View'; |
486 | |
487 | sub process { |
488 | my ($self, $c) = @_; |
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489 | my $template = $c->stash->{template}; |
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490 | my $content = $self->render($c, $template, $c->stash); |
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491 | $c->res->body( $content ); |
492 | } |
493 | |
494 | sub render { |
495 | my ($self, $c, $template, $args) = @_; |
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496 | # prepare content here |
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497 | return $content; |
498 | } |
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499 | 1; |
500 | |
501 | =head2 Plugins |
502 | |
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503 | The first thing to say about plugins is that if you're not sure if |
504 | your module should be a plugin, it probably shouldn't. It once was |
505 | common to add features to Catalyst by writing plugins that provide |
506 | accessors to said functionality. As Catalyst grew more popular, it |
507 | became obvious that this qualifies as bad practice. |
508 | |
509 | By designing your module as a Catalyst plugin, every method you |
510 | implement, import or inherit will be available via your applications |
511 | context object. A plugin pollutes the global namespace, and you |
512 | should be only doing that when you really need to. |
513 | |
514 | Often, developers design extensions as plugins because they need to |
515 | get hold of the context object. Either to get at the stash or |
516 | request/response objects are the widely spread reasons. It is, |
517 | however, perfectly possible to implement a regular Catalyst component |
518 | (read: model, view or controller) that receives the current context |
519 | object via L<Catalyst::Component/"ACCEPT_CONTEXT($c, @args)">. |
520 | |
521 | When is a plugin suited to your task? Your code needs to be a |
522 | plugin to act upon or alter specific parts of Catalyst's request |
523 | lifecycle. If your functionality needs to wrap some C<prepare_*> or |
524 | C<finalize_*> stages, you won't get around a plugin. |
525 | |
526 | Another valid target for a plugin architecture are things that |
527 | B<really> have to be globally available, like sessions or |
528 | authentication. |
529 | |
530 | B<Please do not> release Catalyst extensions as plugins only to |
531 | provide some functionality application wide. Design it as a controller |
532 | base class or another suiting technique with a smaller scope, so that |
533 | your code only influences those parts of the application where it is |
534 | needed, and namespace clashes and conflicts are ruled out. |
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535 | |
536 | The implementation is pretty easy. Your plugin will be inserted in the |
537 | application's inheritance list, above Catalyst itself. You can by this |
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538 | alter Catalyst's request lifecycle behaviour. Every method you |
539 | declare, every import in your package will be available as method on |
540 | the application and the context object. As an example, let's say you |
541 | want Catalyst to warn you every time uri_for returned an undefined |
542 | value, for example because you specified the wrong number of captures |
543 | for the targeted action chain. You could do this with this simple |
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544 | implementation (excuse the lame class name, it's just an example): |
545 | |
546 | package Catalyst::Plugin::UriforUndefWarning; |
547 | use strict; |
548 | use Class::C3; |
549 | |
550 | sub uri_for { |
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551 | my $c = shift; |
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552 | my $uri = $c->next::method(@_); |
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553 | $c->log->warn( 'uri_for returned undef for:', join(', ', @_), ); |
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554 | return $uri; |
555 | } |
556 | |
557 | 1; |
558 | |
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559 | This would override Catalyst's C<uri_for> method and emit a C<warn> |
560 | log entry containing the arguments that led to the undefined return |
561 | value. |
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562 | |
563 | =head2 Factory components with COMPONENT() |
564 | |
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565 | Every component inheriting from L<Catalyst::Component> contains a |
566 | C<COMPONENT> method. It is used on application startup by |
567 | C<setup_components> to instantiate the component object for the |
568 | Catalyst application. By default, this will merge the components own |
569 | C<config>uration with the application wide overrides and call the |
570 | class' C<new> method to return the component object. |
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571 | |
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572 | You can override this method and do and return whatever you want. |
573 | However, you should use L<Class::C3> to forward to the original |
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574 | C<COMPONENT> method to merge the configuration of your component. |
575 | |
576 | Here is a stub C<COMPONENT> method: |
577 | |
578 | package CatalystX::Component::Foo; |
579 | use strict; |
580 | use base 'Catalyst::Component'; |
581 | |
582 | use Class::C3; |
583 | |
584 | sub COMPONENT { |
585 | my $class = shift; |
586 | my ($app_class, $config) = @_; |
587 | |
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588 | # do things here before instantiation my |
589 | $obj = $self->next::method(@_); |
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590 | # do things to object after instantiation |
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591 | return $object; |
592 | } |
593 | |
594 | The arguments are the class name of the component, the class name of |
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595 | the application instantiating the component, and a hash reference with |
596 | the controller's configuration. |
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597 | |
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598 | You are free to re-bless the object, instantiate a whole other |
599 | component or really do anything compatible with Catalyst's |
600 | expectations on a component. |
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601 | |
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602 | For more information, please see L<Catalyst::Component/"COMPONENT($c,$arguments)">. |
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603 | |
604 | =head1 SEE ALSO |
605 | |
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606 | L<Catalyst>, L<Catalyst::Manual::Actions>, L<Catalyst::Component> |
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607 | |
608 | =head1 AUTHOR |
609 | |
1972ebdd |
610 | Robert Sedlacek C<< <rs@474.at> >> |
611 | |
612 | Jonathan Rockway C<< <jrockway@cpan.org> >> |
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613 | |
614 | =head1 LICENSE AND COPYRIGHT |
615 | |
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616 | This document is free, you can redistribute it and/or modify it under |
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617 | the same terms as Perl itself. |
618 | |
619 | =cut |
620 | |