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Net::Curl::Form - Form builder for Net::Curl


 use Net::Curl::Form qw(:constants);

 my $form = Net::Curl::Form->new();
     CURLFORM_COPYNAME() => $name,
     CURLFORM_COPYNAME() => $filename,
     CURLFORM_FILE() => $filename

 # most likely use:
 $easy->setopt( CURLOPT_HTTPPOST() => $form );

 # serialize
 my $serial = $form->get();


This module lets you build multipart/form-data HTTP POST. When finished it can be either supplied to Net::Curl::Easy handle or serialized manually. Net::Curl::Form does not export by default anything, but constants can be exported upon request.

 use Net::Curl::Form qw(:constants);


new( [BASE] )

Creates new Net::Curl::Form object. If BASE is specified it will be used as object base, otherwise an empty hash will be used. BASE must be a valid reference which has not been blessed already. It will not be used by the object.

 my $form = Net::Curl::Form->new( [qw(my very private data)] );


add( CURLFORM_option => DATA, ... )

Adds new section to form object. See curl_formadd(3) for more info.

Unlike in libcurl function, there is no need to add CURLFORM_END as the last argument.

On error this method dies with "Net::Curl::Form::Code" error object.

Buffer and name options automatibally set their length values so there is no need to set length even if there is a NUL character in the data. If you want to shorten the buffer CURLFORM_*LENGTH options must be set inmediatelly after their buffer option, otherwise an CURL_FORMADD_OPTION_TWICE exception will occur.

     CURLFORM_COPYNAME() => "name",
     CURLFORM_COPYCONTENTS() => "content\0binary"
     CURLFORM_PTRNAME() => "name",
     CURLFORM_PTRCONTENTS() => "content",
     CURLFORM_COPYNAME, "htmlcode",
     CURLFORM_CONTENTTYPE, "text/html"
     CURLFORM_COPYNAME, "picture",
     CURLFORM_FILE, "my-face.jpg"
     CURLFORM_COPYNAME, "picture",
     CURLFORM_FILE, "my-face.jpg",
     CURLFORM_CONTENTTYPE, "image/jpeg"
     CURLFORM_COPYNAME, "picture",
     CURLFORM_FILE, "my-face.jpg",
     CURLFORM_FILE, "your-face.jpg",
     CURLFORM_COPYNAME, "filecontent",

Use it to serialize the form object. Normally there is no need to use it because Net::Curl::Easy will serialize it while uploading data.

There are multiple ways to perform serialization:


With no arguments a scalar is returned.

 my $serial = $form->get();
write to file handle

If there is only one argument and it is a GLOB or a GLOB reference, serialized contents will be written to that file handle.

 open my $file, ">", "post.txt";
 $form->get( $file );
write to buffer

If there is only one argument and it is writable, serialized contents will be concatenated to it.

 my $serial;
 $form->get( $serial );

 # same as above
 $form->get( \$serial );
use a callback

With two arguments, second one must be a function that will be called for serialization. First argument is a user data that will be passed to that function.

The callback will receive three arguments: form object, data buffer and user data. It must return the length of the data buffer, otherwise serialization will be aborted.

 sub cb_serial
     my ( $form, $data, $uservar ) = @_;

     # do anything you want

     return length $data;
 $form->get( "userdata", \&cb_serial );

Calls curl_formget(3). Rethrows exceptions from callbacks.


None of those functions are exported, you must use fully qualified names.

strerror( [WHATEVER], CODE )

Return a string for error code CODE. String is extracted from error constant name.

 my $message = Net::Curl::Form->strerror(



Most of those constants can be used in add() method. Currently CURLFORM_STREAM and CURLFORM_ARRAY are not supported. Others will behave in the way described in curl_formadd(3).


If add() fails it will return one of those values.


Callback for get() is described already in "use a callback" subsection.


Net::Curl::Form add() method on failure throws a Net::Curl::Form::Code error object. It has both numeric value and, when used as string, it calls strerror() function to display a nice message.


Net::Curl Net::Curl::Easy curl_formadd(3)


Copyright (c) 2011-2015 Przemyslaw Iskra <sparky at>.

You may opt to use, copy, modify, merge, publish, distribute and/or sell copies of the Software, and permit persons to whom the Software is furnished to do so, under the terms of the MPL or the MIT/X-derivate licenses. You may pick one of these licenses.