NAME

       HTTP::Headers::ActionPack - HTTP Action, Adventure and Excitement

VERSION

       version 0.09

SYNOPSIS

         use HTTP::Headers::ActionPack;

         my $pack       = HTTP::Headers::ActionPack->new;
         my $media_type = $pack->create_header( 'Content-Type' => 'application/xml;charset=UTF-8' );
         my $link       = $pack->create( 'LinkHeader' => [ '</test/tree>', rel => "up" ] );

         # auto-magic header inflation
         # for multiple types
         $pack->inflate( $http_headers_instance );
         $pack->inflate( $http_request_instance );
         $pack->inflate( $plack_request_instance );

DESCRIPTION

       This is a module to handle the inflation and deflation of complex HTTP header types. In
       many cases header values are simple strings, but in some cases they are complex values
       with a lot of information encoded in them. The goal of this module is to make the parsing
       and analysis of these headers as easy as calling "inflate" on a compatible object (see
       below for a list).

       This top-level class is basically a Factory for creating instances of the other classes in
       this module. It contains a number of convenience methods to help make common cases easy to
       write.

DEFAULT MAPPINGS

       This class provides a set of default mappings between HTTP headers and the classes which
       can inflate them. Here is the list of default mappings this class provides.

         Link                HTTP::Headers::ActionPack::LinkList
         Content-Type        HTTP::Headers::ActionPack::MediaType
         Accept              HTTP::Headers::ActionPack::MediaTypeList
         Accept-Charset      HTTP::Headers::ActionPack::PriorityList
         Accept-Encoding     HTTP::Headers::ActionPack::PriorityList
         Accept-Language     HTTP::Headers::ActionPack::PriorityList
         Date                HTTP::Headers::ActionPack::DateHeader
         Client-Date         HTTP::Headers::ActionPack::DateHeader
         Expires             HTTP::Headers::ActionPack::DateHeader
         Last-Modified       HTTP::Headers::ActionPack::DateHeader
         If-Unmodified-Since HTTP::Headers::ActionPack::DateHeader
         If-Modified-Since   HTTP::Headers::ActionPack::DateHeader
         WWW-Authenticate    HTTP::Headers::ActionPack::WWWAuthenticate
         Authentication-Info HTTP::Headers::ActionPack::AuthenticationInfo
         Authorization       HTTP::Headers::ActionPack::Authorization

       NOTE: The 'Client-Date' header is often added by LWP on HTTP::Response objects.

METHODS

       "new( ?%mappings )"
           The constructor takes an option hash of header-name to class mappings to add too (or
           override) the default mappings (see above for details). Each class is expected to have
           a "new_from_string" method which can parse the string representation of the given
           header and return an object.

       "mapping"
           This returns the set of mappings in this instance.

       "classes"
           This returns the list of supported classes, which is by default the list of classes
           included in this modules, but it also will grab any additionally classes that were
           specified in the %mappings parameter to "new" (see above).

       "get_content_negotiator"
           Returns an instance of HTTP::Headers::ActionPack::ContentNegotiation.

       "create( $class_name, $args )"
           This method, given a $class_name and $args, will inflate the value using the class
           found in the "classes" list. If $args is a string it will call "new_from_string" on
           the $class_name, but if $args is an ARRAY ref, it will dereference the ARRAY and pass
           it to "new".

       "create_header( $header_name, $header_value )"
           This method, given a $header_name and a $header_value will inflate the value using the
           class found in the mappings. If $header_value is a string it will call
           "new_from_string" on the class mapped to the $header_name, but if $header_value is an
           ARRAY ref, it will dereference the ARRAY and pass it to "new".

       "inflate( $http_headers )"
       "inflate( $http_request )"
       "inflate( $plack_request )"
       "inflate( $web_request )"
           Given either a HTTP::Headers instance, a HTTP::Request instance, a Plack::Request
           instance, or a Web::Request instance, this method will inflate all the relevant
           headers and store the object in the same instance.

           In theory this should not negatively affect anything since all the header objects
           overload the stringification operator, and most often the headers are treated as
           strings. However, this is not for certain and care should be taken.

CAVEATS

   Plack Compatibility
       We have a test in the suite that checks to make sure that any inflated header objects will
       pass between HTTP::Request and HTTP::Response objects as well as Plack::Request and
       Plack::Response objects.

       A simple survey of most of the Plack::Handler subclasses shows that most of them will end
       up properly stringifying these header objects before sending them out. The notable
       exceptions were the Apache handlers.

       At the time of this writing, the solution for this would be for you to either stringify
       these objects prior to returning your Plack::Response, or to write a simple middleware
       component that would do that for you. In future versions we might provide just such a
       middleware (it would likely inflate the header objects on the request side as well).

   Stringification
       As mentioned above, all the header objects overload the stringification operator, so
       normal usage of them should just do what you would expect (stringify in a sensible way).
       However this is not certain and so care should be taken when passing object headers onto
       another library that is expecting strings.

AUTHOR

       Stevan Little <stevan.little@iinteractive.com>

CONTRIBUTORS

       •   Andrew Nelson <anelson@cpan.org>

       •   Dave Rolsky <autarch@urth.org>

       •   Florian Ragwitz <rafl@debian.org>

       •   Jesse Luehrs <doy@tozt.net>

       •   Karen Etheridge <ether@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2012 by Infinity Interactive, Inc..

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.