1 package Catalyst::Controller::REST;
3 use namespace::autoclean;
6 $VERSION = eval $VERSION;
10 Catalyst::Controller::REST - A RESTful controller
14 package Foo::Controller::Bar;
16 use namespace::autoclean;
18 BEGIN { extends 'Catalyst::Controller::REST' }
20 sub thing : Local : ActionClass('REST') { }
22 # Answer GET requests to "thing"
24 my ( $self, $c ) = @_;
26 # Return a 200 OK, with the data in entity
27 # serialized in the body
32 foo => 'is real bar-y',
37 # Answer PUT requests to "thing"
39 my ( $self, $c ) = @_;
41 $radiohead = $c->req->data->{radiohead};
43 $self->status_created(
45 location => $c->req->uri,
47 radiohead => $radiohead,
54 Catalyst::Controller::REST implements a mechanism for building
55 RESTful services in Catalyst. It does this by extending the
56 normal Catalyst dispatch mechanism to allow for different
57 subroutines to be called based on the HTTP Method requested,
58 while also transparently handling all the serialization/deserialization for
61 This is probably best served by an example. In the above
62 controller, we have declared a Local Catalyst action on
63 "sub thing", and have used the ActionClass('REST').
65 Below, we have declared "thing_GET" and "thing_PUT". Any
66 GET requests to thing will be dispatched to "thing_GET",
67 while any PUT requests will be dispatched to "thing_PUT".
69 Any unimplemented HTTP methods will be met with a "405 Method Not Allowed"
70 response, automatically containing the proper list of available methods. You
71 can override this behavior through implementing a custom
72 C<thing_not_implemented> method.
74 If you do not provide an OPTIONS handler, we will respond to any OPTIONS
75 requests with a "200 OK", populating the Allowed header automatically.
77 Any data included in C<< $c->stash->{'rest'} >> will be serialized for you.
78 The serialization format will be selected based on the content-type
79 of the incoming request. It is probably easier to use the L<STATUS HELPERS>,
80 which are described below.
82 "The HTTP POST, PUT, and OPTIONS methods will all automatically
83 L<deserialize|Catalyst::Action::Deserialize> the contents of
84 C<< $c->request->body >> into the C<< $c->request->data >> hashref", based on
85 the request's C<Content-type> header. A list of understood serialization
86 formats is L<below|/AVAILABLE SERIALIZERS>.
88 If we do not have (or cannot run) a serializer for a given content-type, a 415
89 "Unsupported Media Type" error is generated.
91 To make your Controller RESTful, simply have it
93 BEGIN { extends 'Catalyst::Controller::REST' }
97 See L<Catalyst::Action::Serialize/CONFIGURATION>. Note that the C<serialize>
98 key has been deprecated.
102 Catalyst::Controller::REST will automatically serialize your
103 responses, and deserialize any POST, PUT or OPTIONS requests. It evaluates
104 which serializer to use by mapping a content-type to a Serialization module.
105 We select the content-type based on:
109 =item B<The Content-Type Header>
111 If the incoming HTTP Request had a Content-Type header set, we will use it.
113 =item B<The content-type Query Parameter>
115 If this is a GET request, you can supply a content-type query parameter.
117 =item B<Evaluating the Accept Header>
119 Finally, if the client provided an Accept header, we will evaluate
120 it and use the best-ranked choice.
124 =head1 AVAILABLE SERIALIZERS
126 A given serialization mechanism is only available if you have the underlying
127 modules installed. For example, you can't use XML::Simple if it's not already
130 In addition, each serializer has its quirks in terms of what sorts of data
131 structures it will properly handle. L<Catalyst::Controller::REST> makes
132 no attempt to save you from yourself in this regard. :)
136 =item * C<text/x-yaml> => C<YAML::Syck>
138 Returns YAML generated by L<YAML::Syck>.
140 =item * C<text/html> => C<YAML::HTML>
142 This uses L<YAML::Syck> and L<URI::Find> to generate YAML with all URLs turned
143 to hyperlinks. Only usable for Serialization.
145 =item * C<application/json> => C<JSON>
147 Uses L<JSON> to generate JSON output. It is strongly advised to also have
148 L<JSON::XS> installed. The C<text/x-json> content type is supported but is
149 deprecated and you will receive warnings in your log.
151 You can also add a hash in your controller config to pass options to the json object.
152 For instance, to relax permissions when deserializing input, add:
154 json_options => { relaxed => 1 }
157 =item * C<text/javascript> => C<JSONP>
159 If a callback=? parameter is passed, this returns javascript in the form of: $callback($serializedJSON);
161 Note - this is disabled by default as it can be a security risk if you are unaware.
163 The usual MIME types for this serialization format are: 'text/javascript', 'application/x-javascript',
164 'application/javascript'.
166 =item * C<text/x-data-dumper> => C<Data::Serializer>
168 Uses the L<Data::Serializer> module to generate L<Data::Dumper> output.
170 =item * C<text/x-data-denter> => C<Data::Serializer>
172 Uses the L<Data::Serializer> module to generate L<Data::Denter> output.
174 =item * C<text/x-data-taxi> => C<Data::Serializer>
176 Uses the L<Data::Serializer> module to generate L<Data::Taxi> output.
178 =item * C<text/x-config-general> => C<Data::Serializer>
180 Uses the L<Data::Serializer> module to generate L<Config::General> output.
182 =item * C<text/x-php-serialization> => C<Data::Serializer>
184 Uses the L<Data::Serializer> module to generate L<PHP::Serialization> output.
186 =item * C<text/xml> => C<XML::Simple>
188 Uses L<XML::Simple> to generate XML output. This is probably not suitable
189 for any real heavy XML work. Due to L<XML::Simple>s requirement that the data
190 you serialize be a HASHREF, we transform outgoing data to be in the form of:
192 { data => $yourdata }
196 Uses a regular Catalyst view. For example, if you wanted to have your
197 C<text/html> and C<text/xml> views rendered by TT, set:
201 'text/html' => [ 'View', 'TT' ],
202 'text/xml' => [ 'View', 'XML' ],
206 Your views should have a C<process> method like this:
209 my ( $self, $c, $stash_key ) = @_;
213 $output = $self->serialize( $c->stash->{$stash_key} );
217 $c->response->body( $output );
218 return 1; # important
222 my ( $self, $data ) = @_;
224 my $serialized = ... process $data here ...
231 For infinite flexibility, you can provide a callback for the
232 deserialization/serialization steps.
236 'text/xml' => [ 'Callback', { deserialize => \&parse_xml, serialize => \&render_xml } ],
240 The C<deserialize> callback is passed a string that is the body of the
241 request and is expected to return a scalar value that results from
242 the deserialization. The C<serialize> callback is passed the data
243 structure that needs to be serialized and must return a string suitable
244 for returning in the HTTP response. In addition to receiving the scalar
245 to act on, both callbacks are passed the controller object and the context
246 (i.e. C<$c>) as the second and third arguments.
250 By default, L<Catalyst::Controller::REST> will return a
251 C<415 Unsupported Media Type> response if an attempt to use an unsupported
252 content-type is made. You can ensure that something is always returned by
253 setting the C<default> config option:
255 __PACKAGE__->config(default => 'text/x-yaml');
257 would make it always fall back to the serializer plugin defined for
260 =head1 CUSTOM SERIALIZERS
262 Implementing new Serialization formats is easy! Contributions
263 are most welcome! If you would like to implement a custom serializer,
264 you should create two new modules in the L<Catalyst::Action::Serialize>
265 and L<Catalyst::Action::Deserialize> namespace. Then assign your new
266 class to the content-type's you want, and you're done.
268 See L<Catalyst::Action::Serialize> and L<Catalyst::Action::Deserialize>
269 for more information.
271 =head1 STATUS HELPERS
273 Since so much of REST is in using HTTP, we provide these Status Helpers.
274 Using them will ensure that you are responding with the proper codes,
275 headers, and entities.
277 These helpers try and conform to the HTTP 1.1 Specification. You can
278 refer to it at: L<http://www.w3.org/Protocols/rfc2616/rfc2616.txt>.
279 These routines are all implemented as regular subroutines, and as
280 such require you pass the current context ($c) as the first argument.
286 BEGIN { extends 'Catalyst::Controller' }
287 use Params::Validate qw(SCALAR OBJECT);
289 __PACKAGE__->mk_accessors(qw(serialize));
292 'stash_key' => 'rest',
294 'text/xml' => 'XML::Simple',
295 'application/json' => 'JSON',
296 'text/x-json' => 'JSON',
300 sub begin : ActionClass('Deserialize') { }
302 sub end : ActionClass('Serialize') { }
306 Returns a "200 OK" response. Takes an "entity" to serialize.
313 radiohead => "Is a good band!",
322 my %p = Params::Validate::validate( @_, { entity => 1, }, );
324 $c->response->status(200);
325 $self->_set_entity( $c, $p{'entity'} );
331 Returns a "201 CREATED" response. Takes an "entity" to serialize,
332 and a "location" where the created object can be found.
336 $self->status_created(
338 location => $c->req->uri,
340 radiohead => "Is a good band!",
344 In the above example, we use the requested URI as our location.
345 This is probably what you want for most PUT requests.
352 my %p = Params::Validate::validate(
355 location => { type => SCALAR | OBJECT },
356 entity => { optional => 1 },
360 $c->response->status(201);
361 $c->response->header( 'Location' => $p{location} );
362 $self->_set_entity( $c, $p{'entity'} );
366 =item status_accepted
368 Returns a "202 ACCEPTED" response. Takes an "entity" to serialize.
369 Also takes optional "location" for queue type scenarios.
373 $self->status_accepted(
375 location => $c->req->uri,
383 sub status_accepted {
386 my %p = Params::Validate::validate(
389 location => { type => SCALAR | OBJECT, optional => 1 },
394 $c->response->status(202);
395 $c->response->header( 'Location' => $p{location} ) if exists $p{location};
396 $self->_set_entity( $c, $p{'entity'} );
400 =item status_no_content
402 Returns a "204 NO CONTENT" response.
406 sub status_no_content {
409 $c->response->status(204);
410 $self->_set_entity( $c, undef );
414 =item status_multiple_choices
416 Returns a "300 MULTIPLE CHOICES" response. Takes an "entity" to serialize, which should
417 provide list of possible locations. Also takes optional "location" for preferred choice.
421 sub status_multiple_choices {
424 my %p = Params::Validate::validate(
428 location => { type => SCALAR | OBJECT, optional => 1 },
432 $c->response->status(300);
433 $c->response->header( 'Location' => $p{location} ) if exists $p{'location'};
434 $self->_set_entity( $c, $p{'entity'} );
440 Returns a "302 FOUND" response. Takes an "entity" to serialize.
441 Also takes optional "location".
448 my %p = Params::Validate::validate(
452 location => { type => SCALAR | OBJECT, optional => 1 },
456 $c->response->status(302);
457 $c->response->header( 'Location' => $p{location} ) if exists $p{'location'};
458 $self->_set_entity( $c, $p{'entity'} );
462 =item status_bad_request
464 Returns a "400 BAD REQUEST" response. Takes a "message" argument
465 as a scalar, which will become the value of "error" in the serialized
470 $self->status_bad_request(
472 message => "Cannot do what you have asked!",
477 sub status_bad_request {
480 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
482 $c->response->status(400);
483 $c->log->debug( "Status Bad Request: " . $p{'message'} ) if $c->debug;
484 $self->_set_entity( $c, { error => $p{'message'} } );
488 =item status_forbidden
490 Returns a "403 FORBIDDEN" response. Takes a "message" argument
491 as a scalar, which will become the value of "error" in the serialized
496 $self->status_forbidden(
498 message => "access denied",
503 sub status_forbidden {
506 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
508 $c->response->status(403);
509 $c->log->debug( "Status Forbidden: " . $p{'message'} ) if $c->debug;
510 $self->_set_entity( $c, { error => $p{'message'} } );
514 =item status_not_found
516 Returns a "404 NOT FOUND" response. Takes a "message" argument
517 as a scalar, which will become the value of "error" in the serialized
522 $self->status_not_found(
524 message => "Cannot find what you were looking for!",
529 sub status_not_found {
532 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
534 $c->response->status(404);
535 $c->log->debug( "Status Not Found: " . $p{'message'} ) if $c->debug;
536 $self->_set_entity( $c, { error => $p{'message'} } );
542 Returns a "41O GONE" response. Takes a "message" argument as a scalar,
543 which will become the value of "error" in the serialized response.
549 message => "The document have been deleted by foo",
557 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
559 $c->response->status(410);
560 $c->log->debug( "Status Gone " . $p{'message'} ) if $c->debug;
561 $self->_set_entity( $c, { error => $p{'message'} } );
569 if ( defined($entity) ) {
570 $c->stash->{ $self->{'stash_key'} } = $entity;
577 =head1 MANUAL RESPONSES
579 If you want to construct your responses yourself, all you need to
580 do is put the object you want serialized in $c->stash->{'rest'}.
582 =head1 IMPLEMENTATION DETAILS
584 This Controller ties together L<Catalyst::Action::REST>,
585 L<Catalyst::Action::Serialize> and L<Catalyst::Action::Deserialize>. It should be suitable for most applications. You should be aware that it:
589 =item Configures the Serialization Actions
591 This class provides a default configuration for Serialization. It is currently:
594 'stash_key' => 'rest',
596 'text/html' => 'YAML::HTML',
597 'text/xml' => 'XML::Simple',
598 'text/x-yaml' => 'YAML',
599 'application/json' => 'JSON',
600 'text/x-json' => 'JSON',
601 'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
602 'text/x-data-denter' => [ 'Data::Serializer', 'Data::Denter' ],
603 'text/x-data-taxi' => [ 'Data::Serializer', 'Data::Taxi' ],
604 'application/x-storable' => [ 'Data::Serializer', 'Storable' ],
605 'application/x-freezethaw' => [ 'Data::Serializer', 'FreezeThaw' ],
606 'text/x-config-general' => [ 'Data::Serializer', 'Config::General' ],
607 'text/x-php-serialization' => [ 'Data::Serializer', 'PHP::Serialization' ],
611 You can read the full set of options for this configuration block in
612 L<Catalyst::Action::Serialize>.
614 =item Sets a C<begin> and C<end> method for you
616 The C<begin> method uses L<Catalyst::Action::Deserialize>. The C<end>
617 method uses L<Catalyst::Action::Serialize>. If you want to override
618 either behavior, simply implement your own C<begin> and C<end> actions
619 and forward to another action with the Serialize and/or Deserialize
622 package Foo::Controller::Monkey;
624 use namespace::autoclean;
626 BEGIN { extends 'Catalyst::Controller::REST' }
628 sub begin : Private {
630 ... do things before Deserializing ...
631 $c->forward('deserialize');
632 ... do things after Deserializing ...
635 sub deserialize : ActionClass('Deserialize') {}
639 ... do things before Serializing ...
640 $c->forward('serialize');
641 ... do things after Serializing ...
644 sub serialize : ActionClass('Serialize') {}
646 If you need to deserialize multipart requests (i.e. REST data in
647 one part and file uploads in others) you can do so by using the
648 L<Catalyst::Action::DeserializeMultiPart> action class.
652 =head1 A MILD WARNING
654 I have code in production using L<Catalyst::Controller::REST>. That said,
655 it is still under development, and it's possible that things may change
656 between releases. I promise to not break things unnecessarily. :)
660 L<Catalyst::Action::REST>, L<Catalyst::Action::Serialize>,
661 L<Catalyst::Action::Deserialize>
663 For help with REST in general:
665 The HTTP 1.1 Spec is required reading. http://www.w3.org/Protocols/rfc2616/rfc2616.txt
667 Wikipedia! http://en.wikipedia.org/wiki/Representational_State_Transfer
669 The REST Wiki: http://rest.blueoxen.net/cgi-bin/wiki.pl?FrontPage
673 See L<Catalyst::Action::REST> for authors.
677 You may distribute this code under the same terms as Perl itself.
681 __PACKAGE__->meta->make_immutable;