README

NAME
    Catalyst::Controller::REST - A RESTful controller

SYNOPSIS
        package Foo::Controller::Bar;

        use base 'Catalyst::Controller::REST';

        sub thing : Local : ActionClass('REST') { }

        # Answer GET requests to "thing"
        sub thing_GET {
           my ( $self, $c ) = @_;
     
           # Return a 200 OK, with the data in entity
           # serialized in the body 
           $self->status_ok(
                $c, 
                entity => {
                    some => 'data',
                    foo  => 'is real bar-y',
                },
           );
        }

        # Answer PUT requests to "thing"
        sub thing_PUT { 
          .. some action ..
        }

DESCRIPTION
    Catalyst::Controller::REST implements a mechanism for building RESTful
    services in Catalyst. It does this by extending the normal Catalyst
    dispatch mechanism to allow for different subroutines to be called based
    on the HTTP Method requested, while also transparently handling all the
    serialization/deserialization for you.

    This is probably best served by an example. In the above controller, we
    have declared a Local Catalyst action on "sub thing", and have used the
    ActionClass('REST').

    Below, we have declared "thing_GET" and "thing_PUT". Any GET requests to
    thing will be dispatched to "thing_GET", while any PUT requests will be
    dispatched to "thing_PUT".

    Any unimplemented HTTP methods will be met with a "405 Method Not
    Allowed" response, automatically containing the proper list of available
    methods. You can override this behavior through implementing a custom
    "thing_not_implemented" method.

    If you do not provide an OPTIONS handler, we will respond to any OPTIONS
    requests with a "200 OK", populating the Allowed header automatically.

    Any data included in "$c->stash->{'rest'}" will be serialized for you.
    The serialization format will be selected based on the content-type of
    the incoming request. It is probably easier to use the "STATUS HELPERS",
    which are described below.

    The HTTP POST, PUT, and OPTIONS methods will all automatically
    deserialize the contents of $c->request->body based on the requests
    content-type header. A list of understood serialization formats is
    below.

    If we do not have (or cannot run) a serializer for a given content-type,
    a 415 "Unsupported Media Type" error is generated.

    To make your Controller RESTful, simply have it

      use base 'Catalyst::Controller::REST'; 

SERIALIZATION
    Catalyst::Controller::REST will automatically serialize your responses,
    and deserialize any POST, PUT or OPTIONS requests. It evaluates which
    serializer to use by mapping a content-type to a Serialization module.
    We select the content-type based on:

    The Content-Type Header
      If the incoming HTTP Request had a Content-Type header set, we will
      use it.

    The content-type Query Parameter
      If this is a GET request, you can supply a content-type query
      parameter.

    Evaluating the Accept Header
      Finally, if the client provided an Accept header, we will evaluate it
      and use the best-ranked choice.

AVAILABLE SERIALIZERS
    A given serialization mechanism is only available if you have the
    underlying modules installed. For example, you can't use XML::Simple if
    it's not already installed.

    In addition, each serializer has it's quirks in terms of what sorts of
    data structures it will properly handle. Catalyst::Controller::REST
    makes no attempt to svae you from yourself in this regard. :)

    "text/x-yaml" => "YAML::Syck"
      Returns YAML generated by YAML::Syck.

    "text/html" => "YAML::HTML"
      This uses YAML::Syck and URI::Find to generate YAML with all URLs
      turned to hyperlinks. Only useable for Serialization.

    "text/x-json" => "JSON::Syck"
      Uses JSON::Syck to generate JSON output

    "text/x-data-dumper" => "Data::Serializer"
      Uses the Data::Serializer module to generate Data::Dumper output.

    "text/x-data-denter" => "Data::Serializer"
      Uses the Data::Serializer module to generate Data::Denter output.

    "text/x-data-taxi" => "Data::Serializer"
      Uses the Data::Serializer module to generate Data::Taxi output.

    "application/x-storable" => "Data::Serializer"
      Uses the Data::Serializer module to generate Storable output.

    "application/x-freezethaw" => "Data::Serializer"
      Uses the Data::Serializer module to generate FreezeThaw output.

    "text/x-config-general" => "Data::Serializer"
      Uses the Data::Serializer module to generate Config::General output.

    "text/x-php-serialization" => "Data::Serializer"
      Uses the Data::Serializer module to generate PHP::Serialization
      output.

    "text/xml" => "XML::Simple"
      Uses XML::Simple to generate XML output. This is probably not suitable
      for any real heavy XML work. Due to XML::Simples requirement that the
      data you serialize be a HASHREF, we transform outgoing data to be in
      the form of:

        { data => $yourdata }

    View
      Uses a regular Catalyst view. For example, if you wanted to have your
      "text/html" and "text/xml" views rendered by TT:

              'text/html' => [ 'View', 'TT' ],
              'text/xml'  => [ 'View', 'XML' ],
        
      Will do the trick nicely.

    By default, Catalyst::Controller::REST will return a "415 Unsupported
    Media Type" response if an attempt to use an unsupported content-type is
    made. You can ensure that something is always returned by setting the
    "default" config option:

       __PACKAGE__->config->{'serialize'}->{'default'} = 'text/x-yaml';

    Would make it always fall back to the serializer plugin defined for
    text/x-yaml.

    Implementing new Serialization formats is easy! Contributions are most
    welcome! See Catalyst::Action::Serialize and
    Catalyst::Action::Deserialize for more information.

CUSTOM SERIALIZERS
    If you would like to implement a custom serializer, you should create
    two new modules in the Catalyst::Action::Serialize and
    Catalyst::Action::Deserialize namespace. Then assign your new class to
    the content-type's you want, and you're done.

STATUS HELPERS
    Since so much of REST is in using HTTP, we provide these Status Helpers.
    Using them will ensure that you are responding with the proper codes,
    headers, and entities.

    These helpers try and conform to the HTTP 1.1 Specification. You can
    refer to it at: <http://www.w3.org/Protocols/rfc2616/rfc2616.txt>. These
    routines are all implemented as regular subroutines, and as such require
    you pass the current context ($c) as the first argument.

    status_ok
        Returns a "200 OK" response. Takes an "entity" to serialize.

        Example:

          $self->status_ok(
            $c, 
            entity => {
                radiohead => "Is a good band!",
            }
          );

    status_created
        Returns a "201 CREATED" response. Takes an "entity" to serialize,
        and a "location" where the created object can be found.

        Example:

          $self->status_created(
            $c, 
            location => $c->req->uri->as_string,
            entity => {
                radiohead => "Is a good band!",
            }
          );

        In the above example, we use the requested URI as our location. This
        is probably what you want for most PUT requests.

    status_accepted
        Returns a "202 ACCEPTED" response. Takes an "entity" to serialize.

        Example:

          $self->status_accepted(
            $c, 
            entity => {
                status => "queued",
            }
          );

    status_bad_request
        Returns a "400 BAD REQUEST" response. Takes a "message" argument as
        a scalar, which will become the value of "error" in the serialized
        response.

        Example:

          $self->status_bad_request(
            $c, 
            message => "Cannot do what you have asked!",
          );

    status_not_found
        Returns a "404 NOT FOUND" response. Takes a "message" argument as a
        scalar, which will become the value of "error" in the serialized
        response.

        Example:

          $self->status_not_found(
            $c, 
            message => "Cannot find what you were looking for!",
          );

MANUAL RESPONSES
    If you want to construct your responses yourself, all you need to do is
    put the object you want serialized in $c->stash->{'rest'}.

IMPLEMENTATION DETAILS
    This Controller ties together Catalyst::Action::REST,
    Catalyst::Action::Serialize and Catalyst::Action::Deserialize. It should
    be suitable for most applications. You should be aware that it:

    Configures the Serialization Actions
        This class provides a default configuration for Serialization. It is
        currently:

          __PACKAGE__->config(
              serialize => {
                 'stash_key' => 'rest',
                 'map'       => {
                    'text/html'          => 'YAML::HTML',
                    'text/xml'           => 'XML::Simple',
                    'text/x-yaml'        => 'YAML',
                    'text/x-json'        => 'JSON',
                    'text/x-data-dumper' => [ 'Data::Serializer', 'Data::Dumper' ],
                    'text/x-data-denter' => [ 'Data::Serializer', 'Data::Denter' ],
                    'text/x-data-taxi'   => [ 'Data::Serializer', 'Data::Taxi'   ],
                    'application/x-storable'    => [ 'Data::Serializer', 'Storable'     
        ],
                    'application/x-freezethaw'  => [ 'Data::Serializer', 'FreezeThaw'   
        ],
                    'text/x-config-general' => [ 'Data::Serializer', 'Config::General' ]
        ,
                    'text/x-php-serialization' => [ 'Data::Serializer', 'PHP::Serialization' ],
                  },
              }
          );

        You can read the full set of options for this configuration block in
        Catalyst::Action::Serialize.

    Sets a "begin" and "end" method for you
        The "begin" method uses Catalyst::Action::Deserialize. The "end"
        method uses Catalyst::Action::Serialize. If you want to override
        either behavior, simply implement your own "begin" and "end" actions
        and use NEXT:

          my Foo::Controller::Monkey;
          use base qw(Catalyst::Controller::REST);

          sub begin :Private {
            my ($self, $c) = @_;
            ... do things before Deserializing ...
            $self->NEXT::begin($c); 
            ... do things after Deserializing ...
          } 

          sub end :Private {
            my ($self, $c) = @_;
            ... do things before Serializing ...
            $self->NEXT::end($c); 
            ... do things after Serializing ...
          }

A MILD WARNING
        I have code in production using Catalyst::Controller::REST. That
        said, it is still under development, and it's possible that things
        may change between releases. I promise to not break things
        unneccesarily. :)

SEE ALSO
        Catalyst::Action::REST, Catalyst::Action::Serialize,
        Catalyst::Action::Deserialize

        For help with REST in general:

        The HTTP 1.1 Spec is required reading.
        http://www.w3.org/Protocols/rfc2616/rfc2616.txt

        Wikipedia!
        http://en.wikipedia.org/wiki/Representational_State_Transfer

        The REST Wiki: http://rest.blueoxen.net/cgi-bin/wiki.pl?FrontPage

AUTHOR
        Adam Jacob <adam@stalecoffee.org>, with lots of help from mst and
        jrockway

        Marchex, Inc. paid me while I developed this module.
        (http://www.marchex.com)

LICENSE
        You may distribute this code under the same terms as Perl itself.