1 package Catalyst::Controller::REST;
4 use namespace::autoclean;
8 Catalyst::Controller::REST - A RESTful controller
12 package Foo::Controller::Bar;
14 use namespace::autoclean;
16 BEGIN { extends 'Catalyst::Controller::REST' }
18 sub thing : Local : ActionClass('REST') { }
20 # Answer GET requests to "thing"
22 my ( $self, $c ) = @_;
24 # Return a 200 OK, with the data in entity
25 # serialized in the body
30 foo => 'is real bar-y',
35 # Answer PUT requests to "thing"
37 my ( $self, $c ) = @_;
39 $radiohead = $c->req->data->{radiohead};
41 $self->status_created(
43 location => $c->req->uri,
45 radiohead => $radiohead,
52 Catalyst::Controller::REST implements a mechanism for building
53 RESTful services in Catalyst. It does this by extending the
54 normal Catalyst dispatch mechanism to allow for different
55 subroutines to be called based on the HTTP Method requested,
56 while also transparently handling all the serialization/deserialization for
59 This is probably best served by an example. In the above
60 controller, we have declared a Local Catalyst action on
61 "sub thing", and have used the ActionClass('REST').
63 Below, we have declared "thing_GET" and "thing_PUT". Any
64 GET requests to thing will be dispatched to "thing_GET",
65 while any PUT requests will be dispatched to "thing_PUT".
67 Any unimplemented HTTP methods will be met with a "405 Method Not Allowed"
68 response, automatically containing the proper list of available methods. You
69 can override this behavior through implementing a custom
70 C<thing_not_implemented> method.
72 If you do not provide an OPTIONS handler, we will respond to any OPTIONS
73 requests with a "200 OK", populating the Allowed header automatically.
75 Any data included in C<< $c->stash->{'rest'} >> will be serialized for you.
76 The serialization format will be selected based on the content-type
77 of the incoming request. It is probably easier to use the L<STATUS HELPERS>,
78 which are described below.
80 "The HTTP POST, PUT, and OPTIONS methods will all automatically
81 L<deserialize|Catalyst::Action::Deserialize> the contents of
82 C<< $c->request->body >> into the C<< $c->request->data >> hashref", based on
83 the request's C<Content-type> header. A list of understood serialization
84 formats is L<below|/AVAILABLE SERIALIZERS>.
86 If we do not have (or cannot run) a serializer for a given content-type, a 415
87 "Unsupported Media Type" error is generated.
89 To make your Controller RESTful, simply have it
91 BEGIN { extends 'Catalyst::Controller::REST' }
95 See L<Catalyst::Action::Serialize/CONFIGURATION>. Note that the C<serialize>
96 key has been deprecated.
100 Catalyst::Controller::REST will automatically serialize your
101 responses, and deserialize any POST, PUT or OPTIONS requests. It evaluates
102 which serializer to use by mapping a content-type to a Serialization module.
103 We select the content-type based on:
107 =item B<The Content-Type Header>
109 If the incoming HTTP Request had a Content-Type header set, we will use it.
111 =item B<The content-type Query Parameter>
113 If this is a GET request, you can supply a content-type query parameter.
115 =item B<Evaluating the Accept Header>
117 Finally, if the client provided an Accept header, we will evaluate
118 it and use the best-ranked choice.
122 =head1 AVAILABLE SERIALIZERS
124 A given serialization mechanism is only available if you have the underlying
125 modules installed. For example, you can't use XML::Simple if it's not already
128 In addition, each serializer has its quirks in terms of what sorts of data
129 structures it will properly handle. L<Catalyst::Controller::REST> makes
130 no attempt to save you from yourself in this regard. :)
134 =item * C<text/x-yaml> => C<YAML::Syck>
136 Returns YAML generated by L<YAML::Syck>.
138 =item * C<text/html> => C<YAML::HTML>
140 This uses L<YAML::Syck> and L<URI::Find> to generate YAML with all URLs turned
141 to hyperlinks. Only usable for Serialization.
143 =item * C<application/json> => C<JSON>
145 Uses L<JSON> to generate JSON output. It is strongly advised to also have
146 L<JSON::XS> installed. The C<text/x-json> content type is supported but is
147 deprecated and you will receive warnings in your log.
149 You can also add a hash in your controller config to pass options to the json object.
150 For instance, to relax permissions when deserializing input, add:
152 json_options => { relaxed => 1 }
155 =item * C<text/javascript> => C<JSONP>
157 If a callback=? parameter is passed, this returns javascript in the form of: $callback($serializedJSON);
159 Note - this is disabled by default as it can be a security risk if you are unaware.
161 The usual MIME types for this serialization format are: 'text/javascript', 'application/x-javascript',
162 'application/javascript'.
164 =item * C<text/x-data-dumper> => C<Data::Serializer>
166 Uses the L<Data::Serializer> module to generate L<Data::Dumper> output.
168 =item * C<text/x-data-denter> => C<Data::Serializer>
170 Uses the L<Data::Serializer> module to generate L<Data::Denter> output.
172 =item * C<text/x-data-taxi> => C<Data::Serializer>
174 Uses the L<Data::Serializer> module to generate L<Data::Taxi> output.
176 =item * C<text/x-config-general> => C<Data::Serializer>
178 Uses the L<Data::Serializer> module to generate L<Config::General> output.
180 =item * C<text/x-php-serialization> => C<Data::Serializer>
182 Uses the L<Data::Serializer> module to generate L<PHP::Serialization> output.
184 =item * C<text/xml> => C<XML::Simple>
186 Uses L<XML::Simple> to generate XML output. This is probably not suitable
187 for any real heavy XML work. Due to L<XML::Simple>s requirement that the data
188 you serialize be a HASHREF, we transform outgoing data to be in the form of:
190 { data => $yourdata }
194 Uses a regular Catalyst view. For example, if you wanted to have your
195 C<text/html> and C<text/xml> views rendered by TT, set:
199 'text/html' => [ 'View', 'TT' ],
200 'text/xml' => [ 'View', 'XML' ],
204 Your views should have a C<process> method like this:
207 my ( $self, $c, $stash_key ) = @_;
211 $output = $self->serialize( $c->stash->{$stash_key} );
215 $c->response->body( $output );
216 return 1; # important
220 my ( $self, $data ) = @_;
222 my $serialized = ... process $data here ...
229 For infinite flexibility, you can provide a callback for the
230 deserialization/serialization steps.
234 'text/xml' => [ 'Callback', { deserialize => \&parse_xml, serialize => \&render_xml } ],
238 The C<deserialize> callback is passed a string that is the body of the
239 request and is expected to return a scalar value that results from
240 the deserialization. The C<serialize> callback is passed the data
241 structure that needs to be serialized and must return a string suitable
242 for returning in the HTTP response. In addition to receiving the scalar
243 to act on, both callbacks are passed the controller object and the context
244 (i.e. C<$c>) as the second and third arguments.
248 By default, L<Catalyst::Controller::REST> will return a
249 C<415 Unsupported Media Type> response if an attempt to use an unsupported
250 content-type is made. You can ensure that something is always returned by
251 setting the C<default> config option:
253 __PACKAGE__->config(default => 'text/x-yaml');
255 would make it always fall back to the serializer plugin defined for
258 =head1 CUSTOM SERIALIZERS
260 Implementing new Serialization formats is easy! Contributions
261 are most welcome! If you would like to implement a custom serializer,
262 you should create two new modules in the L<Catalyst::Action::Serialize>
263 and L<Catalyst::Action::Deserialize> namespace. Then assign your new
264 class to the content-type's you want, and you're done.
266 See L<Catalyst::Action::Serialize> and L<Catalyst::Action::Deserialize>
267 for more information.
269 =head1 STATUS HELPERS
271 Since so much of REST is in using HTTP, we provide these Status Helpers.
272 Using them will ensure that you are responding with the proper codes,
273 headers, and entities.
275 These helpers try and conform to the HTTP 1.1 Specification. You can
276 refer to it at: L<http://www.w3.org/Protocols/rfc2616/rfc2616.txt>.
277 These routines are all implemented as regular subroutines, and as
278 such require you pass the current context ($c) as the first argument.
284 BEGIN { extends 'Catalyst::Controller' }
285 use Params::Validate qw(SCALAR OBJECT);
287 __PACKAGE__->mk_accessors(qw(serialize));
290 'stash_key' => 'rest',
292 'text/xml' => 'XML::Simple',
293 'application/json' => 'JSON',
294 'text/x-json' => 'JSON',
298 sub begin : ActionClass('Deserialize') { }
300 sub end : ActionClass('Serialize') { }
304 Returns a "200 OK" response. Takes an "entity" to serialize.
311 radiohead => "Is a good band!",
320 my %p = Params::Validate::validate( @_, { entity => 1, }, );
322 $c->response->status(200);
323 $self->_set_entity( $c, $p{'entity'} );
329 Returns a "201 CREATED" response. Takes an "entity" to serialize,
330 and a "location" where the created object can be found.
334 $self->status_created(
336 location => $c->req->uri,
338 radiohead => "Is a good band!",
342 In the above example, we use the requested URI as our location.
343 This is probably what you want for most PUT requests.
350 my %p = Params::Validate::validate(
353 location => { type => SCALAR | OBJECT },
354 entity => { optional => 1 },
358 $c->response->status(201);
359 $c->response->header( 'Location' => $p{location} );
360 $self->_set_entity( $c, $p{'entity'} );
364 =item status_accepted
366 Returns a "202 ACCEPTED" response. Takes an "entity" to serialize.
367 Also takes optional "location" for queue type scenarios.
371 $self->status_accepted(
373 location => $c->req->uri,
381 sub status_accepted {
384 my %p = Params::Validate::validate(
387 location => { type => SCALAR | OBJECT, optional => 1 },
392 $c->response->status(202);
393 $c->response->header( 'Location' => $p{location} ) if exists $p{location};
394 $self->_set_entity( $c, $p{'entity'} );
398 =item status_no_content
400 Returns a "204 NO CONTENT" response.
404 sub status_no_content {
407 $c->response->status(204);
408 $self->_set_entity( $c, undef );
412 =item status_multiple_choices
414 Returns a "300 MULTIPLE CHOICES" response. Takes an "entity" to serialize, which should
415 provide list of possible locations. Also takes optional "location" for preferred choice.
419 sub status_multiple_choices {
422 my %p = Params::Validate::validate(
426 location => { type => SCALAR | OBJECT, optional => 1 },
430 $c->response->status(300);
431 $c->response->header( 'Location' => $p{location} ) if exists $p{'location'};
432 $self->_set_entity( $c, $p{'entity'} );
438 Returns a "302 FOUND" response. Takes an "entity" to serialize.
439 Also takes optional "location".
446 my %p = Params::Validate::validate(
450 location => { type => SCALAR | OBJECT, optional => 1 },
454 $c->response->status(302);
455 $c->response->header( 'Location' => $p{location} ) if exists $p{'location'};
456 $self->_set_entity( $c, $p{'entity'} );
460 =item status_bad_request
462 Returns a "400 BAD REQUEST" response. Takes a "message" argument
463 as a scalar, which will become the value of "error" in the serialized
468 $self->status_bad_request(
470 message => "Cannot do what you have asked!",
475 sub status_bad_request {
478 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
480 $c->response->status(400);
481 $c->log->debug( "Status Bad Request: " . $p{'message'} ) if $c->debug;
482 $self->_set_entity( $c, { error => $p{'message'} } );
486 =item status_forbidden
488 Returns a "403 FORBIDDEN" response. Takes a "message" argument
489 as a scalar, which will become the value of "error" in the serialized
494 $self->status_forbidden(
496 message => "access denied",
501 sub status_forbidden {
504 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
506 $c->response->status(403);
507 $c->log->debug( "Status Forbidden: " . $p{'message'} ) if $c->debug;
508 $self->_set_entity( $c, { error => $p{'message'} } );
512 =item status_not_found
514 Returns a "404 NOT FOUND" response. Takes a "message" argument
515 as a scalar, which will become the value of "error" in the serialized
520 $self->status_not_found(
522 message => "Cannot find what you were looking for!",
527 sub status_not_found {
530 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
532 $c->response->status(404);
533 $c->log->debug( "Status Not Found: " . $p{'message'} ) if $c->debug;
534 $self->_set_entity( $c, { error => $p{'message'} } );
540 Returns a "41O GONE" response. Takes a "message" argument as a scalar,
541 which will become the value of "error" in the serialized response.
547 message => "The document have been deleted by foo",
555 my %p = Params::Validate::validate( @_, { message => { type => SCALAR }, }, );
557 $c->response->status(410);
558 $c->log->debug( "Status Gone " . $p{'message'} ) if $c->debug;
559 $self->_set_entity( $c, { error => $p{'message'} } );
563 =item status_see_other
565 Returns a "303 See Other" response. Takes an optional "entity" to serialize,
566 and a "location" where the client should redirect to.
570 $self->status_see_other(
572 location => $some_other_url,
574 radiohead => "Is a good band!",
580 sub status_see_other {
583 my %p = Params::Validate::validate(
586 location => { type => SCALAR | OBJECT },
587 entity => { optional => 1 },
591 $c->response->status(303);
592 $c->response->header( 'Location' => $p{location} );
593 $self->_set_entity( $c, $p{'entity'} );
599 Returns a "301 MOVED" response. Takes an "entity" to serialize, and a
600 "location" where the created object can be found.
606 location => '/somewhere/else',
608 radiohead => "Is a good band!",
617 my %p = Params::Validate::validate(
620 location => { type => SCALAR | OBJECT },
621 entity => { optional => 1 },
625 my $location = ref $p{location}
626 ? $p{location}->as_string
630 $c->response->status(301);
631 $c->response->header( Location => $location );
632 $self->_set_entity($c, $p{entity});
640 if ( defined($entity) ) {
641 $c->stash->{ $self->{'stash_key'} } = $entity;
648 =head1 MANUAL RESPONSES
650 If you want to construct your responses yourself, all you need to
651 do is put the object you want serialized in $c->stash->{'rest'}.
653 =head1 IMPLEMENTATION DETAILS
655 This Controller ties together L<Catalyst::Action::REST>,
656 L<Catalyst::Action::Serialize> and L<Catalyst::Action::Deserialize>. It should be suitable for most applications. You should be aware that it:
660 =item Configures the Serialization Actions
662 This class provides a default configuration for Serialization. It is currently:
665 'stash_key' => 'rest',
667 'text/html' => 'YAML::HTML',
668 'text/xml' => 'XML::Simple',
669 'text/x-yaml' => 'YAML',
670 'application/json' => 'JSON',
671 'text/x-json' => 'JSON',
672 'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
673 'text/x-data-denter' => [ 'Data::Serializer', 'Data::Denter' ],
674 'text/x-data-taxi' => [ 'Data::Serializer', 'Data::Taxi' ],
675 'application/x-storable' => [ 'Data::Serializer', 'Storable' ],
676 'application/x-freezethaw' => [ 'Data::Serializer', 'FreezeThaw' ],
677 'text/x-config-general' => [ 'Data::Serializer', 'Config::General' ],
678 'text/x-php-serialization' => [ 'Data::Serializer', 'PHP::Serialization' ],
682 You can read the full set of options for this configuration block in
683 L<Catalyst::Action::Serialize>.
685 =item Sets a C<begin> and C<end> method for you
687 The C<begin> method uses L<Catalyst::Action::Deserialize>. The C<end>
688 method uses L<Catalyst::Action::Serialize>. If you want to override
689 either behavior, simply implement your own C<begin> and C<end> actions
690 and forward to another action with the Serialize and/or Deserialize
693 package Foo::Controller::Monkey;
695 use namespace::autoclean;
697 BEGIN { extends 'Catalyst::Controller::REST' }
699 sub begin : Private {
701 ... do things before Deserializing ...
702 $c->forward('deserialize');
703 ... do things after Deserializing ...
706 sub deserialize : ActionClass('Deserialize') {}
710 ... do things before Serializing ...
711 $c->forward('serialize');
712 ... do things after Serializing ...
715 sub serialize : ActionClass('Serialize') {}
717 If you need to deserialize multipart requests (i.e. REST data in
718 one part and file uploads in others) you can do so by using the
719 L<Catalyst::Action::DeserializeMultiPart> action class.
723 =head1 A MILD WARNING
725 I have code in production using L<Catalyst::Controller::REST>. That said,
726 it is still under development, and it's possible that things may change
727 between releases. I promise to not break things unnecessarily. :)
731 L<Catalyst::Action::REST>, L<Catalyst::Action::Serialize>,
732 L<Catalyst::Action::Deserialize>
734 For help with REST in general:
736 The HTTP 1.1 Spec is required reading. http://www.w3.org/Protocols/rfc2616/rfc2616.txt
738 Wikipedia! http://en.wikipedia.org/wiki/Representational_State_Transfer
740 The REST Wiki: http://rest.blueoxen.net/cgi-bin/wiki.pl?FrontPage
744 See L<Catalyst::Action::REST> for authors.
748 You may distribute this code under the same terms as Perl itself.
752 __PACKAGE__->meta->make_immutable;