# NAME

HTTP::Entity::Parser - PSGI compliant HTTP Entity Parser

# SYNOPSIS

   use HTTP::Entity::Parser;

   my $parser = HTTP::Entity::Parser->new;
   $parser->register('application/x-www-form-urlencoded','HTTP::Entity::Parser::UrlEncoded');
   $parser->register('multipart/form-data','HTTP::Entity::Parser::MultiPart');
   $parser->register('application/json','HTTP::Entity::Parser::JSON');

   sub app {
       my $env = shift;
       my ( $params, $uploads) = $parser->parse($env);
   }

# DESCRIPTION

HTTP::Entity::Parser is a PSGI-compliant HTTP Entity parser. This module also is compatible
with [HTTP::Body](https://metacpan.org/pod/HTTP%3A%3ABody). Unlike HTTP::Body, HTTP::Entity::Parser reads HTTP entities from
PSGI's environment `$env->{'psgi.input'}` and parses it.
This module supports application/x-www-form-urlencoded, multipart/form-data and application/json.

# METHODS

- new( buffer\_length => $length:Intger)

   Create the instance.

   - buffer\_length

       The buffer length that HTTP::Entity::Parser reads from psgi.input. 16384 by default.

- register($content\_type:String, $class:String, $opts:HashRef)

   Register parser class.

       $parser->register('application/x-www-form-urlencoded','HTTP::Entity::Parser::UrlEncoded');
       $parser->register('multipart/form-data','HTTP::Entity::Parser::MultiPart');
       $parser->register('application/json','HTTP::Entity::Parser::JSON');

   If the request content\_type matches the registered type, HTTP::Entity::Parser uses the registered
   parser class. If content\_type does not match any registered type, HTTP::Entity::Parser::OctetStream is used.

- parse($env:HashRef)

   parse HTTP entities from PSGI's env.

       my ( $params:ArrayRef, $uploads:ArrayRef) = $parser->parse($env);

   `$param` is a key-value pair list.

       my ( $params, $uploads) = $parser->parse($env);
       my $body_parameters = Hash::MultiValue->new(@$params);

   `$uploads` is an ArrayRef of HashRef.

       my ( $params, $uploads) = $parser->parse($env);
       warn Dumper($uploads->[0]);
       {
           "name" => "upload", #field name
           "headers" => [
               "Content-Type" => "application/octet-stream",
               "Content-Disposition" => "form-data; name=\"upload\"; filename=\"hello.pl\""
           ],
           "size" => 78, #size of upload content
           "filename" => "hello.png", #original filename in the client
           "tempname" => "/tmp/XXXXX", # path to the temporary file where uploaded file is saved
       }

   When used with [Plack::Request::Upload](https://metacpan.org/pod/Plack%3A%3ARequest%3A%3AUpload):

       my ( $params, $uploads) = $parser->parse($env);
        my $upload_hmv = Hash::MultiValue->new();
        while ( my ($k,$v) = splice @$uploads, 0, 2 ) {
            my %copy = %$v;
            $copy{headers} = HTTP::Headers::Fast->new(@{$v->{headers}});
            $upload_hmv->add($k, Plack::Request::Upload->new(%copy));
        }

# PARSERS

- OctetStream

   Default parser, This parser does not parse entity, always return empty list.

- UrlEncoded

   For `application/x-www-form-urlencoded`. It is used for HTTP POST without file upload

- MultiPart

   For `multipart/form-data`. It is used for HTTP POST contains file upload.

   MultiPart parser use [HTTP::MultiPartParser](https://metacpan.org/pod/HTTP%3A%3AMultiPartParser).

- JSON

   For `application/json`. This parser decodes JSON body automatically.

   It is convenient to use with Ajax forms.

# WHAT'S DIFFERENT FROM HTTP::Body

HTTP::Entity::Parser accept PSGI's env and read body from it.

HTTP::Entity::Parser is able to choose parsers by the instance, HTTP::Body requires to modify global variables.

# SEE ALSO

- [HTTP::Body](https://metacpan.org/pod/HTTP%3A%3ABody)
- [HTTP::MultiPartParser](https://metacpan.org/pod/HTTP%3A%3AMultiPartParser)
- [Plack::Request](https://metacpan.org/pod/Plack%3A%3ARequest)
- [WWW::Form::UrlEncoded](https://metacpan.org/pod/WWW%3A%3AForm%3A%3AUrlEncoded)

   HTTP::Entity::Parser uses this for parse application/x-www-form-urlencoded

# LICENSE

Copyright (C) Masahiro Nagano.

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

# AUTHOR

Masahiro Nagano <[email protected]>

Tokuhiro Matsuno <[email protected]>

This module is based on tokuhirom's code, see [https://github.com/plack/Plack/pull/434](https://github.com/plack/Plack/pull/434)