1 package Catalyst::Controller::REST;
5 Catalyst::Controller::REST - A RESTful controller
9 package Foo::Controller::Bar;
11 use base 'Catalyst::Controller::REST';
13 sub thing : Local : ActionClass('REST') { }
15 # Answer GET requests to "thing"
17 my ( $self, $c ) = @_;
19 # Return a 200 OK, with the data in entity
20 # serialized in the body
25 foo => 'is real bar-y',
30 # Answer PUT requests to "thing"
37 Catalyst::Controller::REST implements a mechanism for building
38 RESTful services in Catalyst. It does this by extending the
39 normal Catalyst dispatch mechanism to allow for different
40 subroutines to be called based on the HTTP Method requested,
41 while also transparently handling all the serialization/deserialization for
44 This is probably best served by an example. In the above
45 controller, we have declared a Local Catalyst action on
46 "sub thing", and have used the ActionClass('REST').
48 Below, we have declared "thing_GET" and "thing_PUT". Any
49 GET requests to thing will be dispatched to "thing_GET",
50 while any PUT requests will be dispatched to "thing_PUT".
52 Any unimplemented HTTP methods will be met with a "405 Method Not Allowed"
53 response, automatically containing the proper list of available methods. You
54 can override this behavior through implementing a custom
55 C<thing_not_implemented> method.
57 If you do not provide an OPTIONS handler, we will respond to any OPTIONS
58 requests with a "200 OK", populating the Allowed header automatically.
60 Any data included in C<< $c->stash->{'rest'} >> will be serialized for you.
61 The serialization format will be selected based on the content-type
62 of the incoming request. It is probably easier to use the L<STATUS HELPERS>,
63 which are described below.
65 The HTTP POST, PUT, and OPTIONS methods will all automatically deserialize the
66 contents of $c->request->body based on the requests content-type header.
67 A list of understood serialization formats is below.
69 If we do not have (or cannot run) a serializer for a given content-type, a 415
70 "Unsupported Media Type" error is generated.
72 To make your Controller RESTful, simply have it
74 use base 'Catalyst::Controller::REST';
78 Catalyst::Controller::REST will automatically serialize your
79 responses, and deserialize any POST, PUT or OPTIONS requests. It evaluates
80 which serializer to use by mapping a content-type to a Serialization module.
81 We select the content-type based on:
85 =item B<The Content-Type Header>
87 If the incoming HTTP Request had a Content-Type header set, we will use it.
89 =item B<The content-type Query Parameter>
91 If this is a GET request, you can supply a content-type query parameter.
93 =item B<Evaluating the Accept Header>
95 Finally, if the client provided an Accept header, we will evaluate
96 it and use the best-ranked choice.
100 =head1 AVAILABLE SERIALIZERS
102 A given serialization mechanism is only available if you have the underlying
103 modules installed. For example, you can't use XML::Simple if it's not already
106 In addition, each serializer has it's quirks in terms of what sorts of data
107 structures it will properly handle. L<Catalyst::Controller::REST> makes
108 no attempt to svae you from yourself in this regard. :)
112 =item C<text/x-yaml> => C<YAML::Syck>
114 Returns YAML generated by L<YAML::Syck>.
116 =item C<text/html> => C<YAML::HTML>
118 This uses L<YAML::Syck> and L<URI::Find> to generate YAML with all URLs turned
119 to hyperlinks. Only useable for Serialization.
121 =item C<text/x-json> => C<JSON::Syck>
123 Uses L<JSON::Syck> to generate JSON output
125 =item C<text/x-data-dumper> => C<Data::Serializer>
127 Uses the L<Data::Serializer> module to generate L<Data::Dumper> output.
129 =item C<text/x-data-denter> => C<Data::Serializer>
131 Uses the L<Data::Serializer> module to generate L<Data::Denter> output.
133 =item C<text/x-data-taxi> => C<Data::Serializer>
135 Uses the L<Data::Serializer> module to generate L<Data::Taxi> output.
137 =item C<application/x-storable> => C<Data::Serializer>
139 Uses the L<Data::Serializer> module to generate L<Storable> output.
141 =item C<application/x-freezethaw> => C<Data::Serializer>
143 Uses the L<Data::Serializer> module to generate L<FreezeThaw> output.
145 =item C<text/x-config-general> => C<Data::Serializer>
147 Uses the L<Data::Serializer> module to generate L<Config::General> output.
149 =item C<text/x-php-serialization> => C<Data::Serializer>
151 Uses the L<Data::Serializer> module to generate L<PHP::Serialization> output.
153 =item C<text/xml> => C<XML::Simple>
155 Uses L<XML::Simple> to generate XML output. This is probably not suitable
156 for any real heavy XML work. Due to L<XML::Simple>s requirement that the data
157 you serialize be a HASHREF, we transform outgoing data to be in the form of:
159 { data => $yourdata }
163 Uses a regular Catalyst view. For example, if you wanted to have your
164 C<text/html> and C<text/xml> views rendered by TT:
166 'text/html' => [ 'View', 'TT' ],
167 'text/xml' => [ 'View', 'XML' ],
169 Will do the trick nicely.
173 By default, L<Catalyst::Controller::REST> will return a C<415 Unsupported Media Type>
174 response if an attempt to use an unsupported content-type is made. You
175 can ensure that something is always returned by setting the C<default>
178 __PACKAGE__->config->{'default'} = 'text/x-yaml';
180 Would make it always fall back to the serializer plugin defined for text/x-yaml.
182 Implementing new Serialization formats is easy! Contributions
183 are most welcome! See L<Catalyst::Action::Serialize> and
184 L<Catalyst::Action::Deserialize> for more information.
186 =head1 CUSTOM SERIALIZERS
188 If you would like to implement a custom serializer, you should create two new
189 modules in the L<Catalyst::Action::Serialize> and
190 L<Catalyst::Action::Deserialize> namespace. Then assign your new class
191 to the content-type's you want, and you're done.
193 =head1 STATUS HELPERS
195 Since so much of REST is in using HTTP, we provide these Status Helpers.
196 Using them will ensure that you are responding with the proper codes,
197 headers, and entities.
199 These helpers try and conform to the HTTP 1.1 Specification. You can
200 refer to it at: L<http://www.w3.org/Protocols/rfc2616/rfc2616.txt>.
201 These routines are all implemented as regular subroutines, and as
202 such require you pass the current context ($c) as the first argument.
210 use base 'Catalyst::Controller';
211 use Params::Validate qw(:all);
213 __PACKAGE__->mk_accessors(qw(serialize));
216 'stash_key' => 'rest',
218 'text/html' => 'YAML::HTML',
219 'text/xml' => 'XML::Simple',
220 'text/x-yaml' => 'YAML',
221 'text/x-json' => 'JSON',
222 'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
223 'text/x-data-denter' => [ 'Data::Serializer', 'Data::Denter' ],
224 'text/x-data-taxi' => [ 'Data::Serializer', 'Data::Taxi' ],
225 'application/x-storable' => [ 'Data::Serializer', 'Storable' ],
226 'application/x-freezethaw' => [ 'Data::Serializer', 'FreezeThaw' ],
227 'text/x-config-general' => [ 'Data::Serializer', 'Config::General' ],
228 'text/x-php-serialization' => [ 'Data::Serializer', 'PHP::Serialization' ],
232 sub begin : ActionClass('Deserialize') {
235 sub end : ActionClass('Serialize') {
240 Returns a "200 OK" response. Takes an "entity" to serialize.
247 radiohead => "Is a good band!",
256 my %p = validate( @_, { entity => 1, }, );
258 $c->response->status(200);
259 $self->_set_entity( $c, $p{'entity'} );
265 Returns a "201 CREATED" response. Takes an "entity" to serialize,
266 and a "location" where the created object can be found.
270 $self->status_created(
272 location => $c->req->uri->as_string,
274 radiohead => "Is a good band!",
278 In the above example, we use the requested URI as our location.
279 This is probably what you want for most PUT requests.
289 location => { type => SCALAR | OBJECT },
290 entity => { optional => 1 },
295 if ( ref( $p{'location'} ) ) {
296 $location = $p{'location'}->as_string;
298 $location = $p{'location'};
300 $c->response->status(201);
301 $c->response->header( 'Location' => $location );
302 $self->_set_entity( $c, $p{'entity'} );
306 =item status_accepted
308 Returns a "202 ACCEPTED" response. Takes an "entity" to serialize.
312 $self->status_accepted(
321 sub status_accepted {
324 my %p = validate( @_, { entity => 1, }, );
326 $c->response->status(202);
327 $self->_set_entity( $c, $p{'entity'} );
331 =item status_bad_request
333 Returns a "400 BAD REQUEST" response. Takes a "message" argument
334 as a scalar, which will become the value of "error" in the serialized
339 $self->status_bad_request(
341 message => "Cannot do what you have asked!",
346 sub status_bad_request {
349 my %p = validate( @_, { message => { type => SCALAR }, }, );
351 $c->response->status(400);
352 $c->log->debug( "Status Bad Request: " . $p{'message'} ) if $c->debug;
353 $self->_set_entity( $c, { error => $p{'message'} } );
357 =item status_not_found
359 Returns a "404 NOT FOUND" response. Takes a "message" argument
360 as a scalar, which will become the value of "error" in the serialized
365 $self->status_not_found(
367 message => "Cannot find what you were looking for!",
372 sub status_not_found {
375 my %p = validate( @_, { message => { type => SCALAR }, }, );
377 $c->response->status(404);
378 $c->log->debug( "Status Not Found: " . $p{'message'} ) if $c->debug;
379 $self->_set_entity( $c, { error => $p{'message'} } );
387 if ( defined($entity) ) {
388 $c->stash->{ $self->{'stash_key'} } = $entity;
395 =head1 MANUAL RESPONSES
397 If you want to construct your responses yourself, all you need to
398 do is put the object you want serialized in $c->stash->{'rest'}.
400 =head1 IMPLEMENTATION DETAILS
402 This Controller ties together L<Catalyst::Action::REST>,
403 L<Catalyst::Action::Serialize> and L<Catalyst::Action::Deserialize>. It should be suitable for most applications. You should be aware that it:
407 =item Configures the Serialization Actions
409 This class provides a default configuration for Serialization. It is currently:
413 'stash_key' => 'rest',
415 'text/html' => 'YAML::HTML',
416 'text/xml' => 'XML::Simple',
417 'text/x-yaml' => 'YAML',
418 'text/x-json' => 'JSON',
419 'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
420 'text/x-data-denter' => [ 'Data::Serializer', 'Data::Denter' ],
421 'text/x-data-taxi' => [ 'Data::Serializer', 'Data::Taxi' ],
422 'application/x-storable' => [ 'Data::Serializer', 'Storable'
424 'application/x-freezethaw' => [ 'Data::Serializer', 'FreezeThaw'
426 'text/x-config-general' => [ 'Data::Serializer', 'Config::General' ]
428 'text/x-php-serialization' => [ 'Data::Serializer', 'PHP::Serialization' ],
433 You can read the full set of options for this configuration block in
434 L<Catalyst::Action::Serialize>.
436 =item Sets a C<begin> and C<end> method for you
438 The C<begin> method uses L<Catalyst::Action::Deserialize>. The C<end>
439 method uses L<Catalyst::Action::Serialize>. If you want to override
440 either behavior, simply implement your own C<begin> and C<end> actions
443 my Foo::Controller::Monkey;
444 use base qw(Catalyst::Controller::REST);
448 ... do things before Deserializing ...
449 $self->NEXT::begin($c);
450 ... do things after Deserializing ...
455 ... do things before Serializing ...
456 $self->NEXT::end($c);
457 ... do things after Serializing ...
460 =head1 A MILD WARNING
462 I have code in production using L<Catalyst::Controller::REST>. That said,
463 it is still under development, and it's possible that things may change
464 between releases. I promise to not break things unneccesarily. :)
468 L<Catalyst::Action::REST>, L<Catalyst::Action::Serialize>,
469 L<Catalyst::Action::Deserialize>
471 For help with REST in general:
473 The HTTP 1.1 Spec is required reading. http://www.w3.org/Protocols/rfc2616/rfc2616.txt
475 Wikipedia! http://en.wikipedia.org/wiki/Representational_State_Transfer
477 The REST Wiki: http://rest.blueoxen.net/cgi-bin/wiki.pl?FrontPage
481 Adam Jacob <adam@stalecoffee.org>, with lots of help from mst and jrockway
483 Marchex, Inc. paid me while I developed this module. (http://www.marchex.com)
487 You may distribute this code under the same terms as Perl itself.