NAME

       CPAN::Meta::History::Meta_1_0 - Version 1.0 metadata specification for META.yml

PREFACE

       This is a historical copy of the version 1.0 specification for META.yml files, copyright
       by Ken Williams and licensed under the same terms as Perl itself.

       Modifications from the original:

       •   Conversion from the original HTML to POD format

       •   Include list of valid licenses from Module::Build 0.17 rather than linking to the
           module, with minor updates to text and links to reflect versions at the time of
           publication.

       •   Fixed some dead links to point to active resources.

DESCRIPTION

       This document describes version 1.0 of the META.yml specification.

       The META.yml file describes important properties of contributed Perl distributions such as
       the ones found on CPAN <http://www.cpan.org>.  It is typically created by tools like
       Module::Build and ExtUtils::MakeMaker.

       The fields in the META.yml file are meant to be helpful to people maintaining module
       collections (like CPAN), for people writing installation tools (like CPAN or CPANPLUS), or
       just people who want to know some stuff about a distribution before downloading it and
       starting to install it.

Format

       META.yml files are written in the YAML <http://www.yaml.org/> format.  The reasons we
       chose YAML instead of, say, XML or Data::Dumper are discussed in this thread
       <http://www.nntp.perl.org/group/perl.makemaker/2002/04/msg406.html> on the MakeMaker
       mailing list.

       The first line of a META.yml file should be a valid YAML document header
       <http://yaml.org/spec/history/2002-10-31.html#syntax-document> like "--- #YAML:1.0"

Fields

       The rest of the META.yml file is one big YAML mapping
       <http://yaml.org/spec/history/2002-10-31.html#syntax-mapping>, whose keys are described
       here.

       name
           Example: "Module-Build"

           The name of the distribution.  Often created by taking the "main module" in the
           distribution and changing "::" to "-".  Sometimes it's completely different, however,
           as in the case of the libwww-perl <http://search.cpan.org/author/GAAS/libwww-perl/>
           distribution.

       version
           Example: 0.16

           The version of the distribution to which the META.yml file refers.

       license
           Example: "perl"

           The license under which this distribution may be used and redistributed.

           Must be one of the following licenses:

           perl
               The distribution may be copied and redistributed under the same terms as perl
               itself (this is by far the most common licensing option for modules on CPAN).
               This is a dual license, in which the user may choose between either the GPL
               version 1 or the Artistic version 1 license.

           gpl The distribution is distributed under the terms of the GNU General Public License
               version 2 (<http://opensource.org/licenses/GPL-2.0>).

           lgpl
               The distribution is distributed under the terms of the GNU Lesser General Public
               License version 2 (<http://opensource.org/licenses/LGPL-2.1>).

           artistic
               The distribution is licensed under the Artistic License version 1, as specified by
               the Artistic file in the standard perl distribution
               (<http://opensource.org/licenses/Artistic-Perl-1.0>).

           bsd The distribution is licensed under the BSD 3-Clause License
               (<http://opensource.org/licenses/BSD-3-Clause>).

           open_source
               The distribution is licensed under some other Open Source Initiative-approved
               license listed at <http://www.opensource.org/licenses/>.

           unrestricted
               The distribution is licensed under a license that is not approved by
               www.opensource.org <http://www.opensource.org/> but that allows distribution
               without restrictions.

           restrictive
               The distribution may not be redistributed without special permission from the
               author and/or copyright holder.

       distribution_type
           Example: "module"

           What kind of stuff is contained in this distribution.  Most things on CPAN are
           "module"s (which can also mean a collection of modules), but some things are
           "script"s.

       requires
           Example:

             Data::Dumper: 0
             File::Find: 1.03

           A YAML mapping <http://yaml.org/spec/history/2002-10-31.html#syntax-mapping>
           indicating the Perl modules this distribution requires for proper operation.  The keys
           are the module names, and the values are version specifications as described in the
           documentation for Module::Build's "requires" parameter.

           Note: the exact nature of the fancy specifications like ">= 1.2, != 1.5, < 2.0" is
           subject to change.  Advance notice will be given here.  The simple specifications like
           "1.2" will not change in format.

       recommends
           Example:

             Data::Dumper: 0
             File::Find: 1.03

           A YAML mapping <http://yaml.org/spec/history/2002-10-31.html#syntax-mapping>
           indicating the Perl modules this distribution recommends for enhanced operation.

       build_requires
           Example:

             Data::Dumper: 0
             File::Find: 1.03

           A YAML mapping <http://yaml.org/spec/history/2002-10-31.html#syntax-mapping>
           indicating the Perl modules required for building and/or testing of this distribution.
           These dependencies are not required after the module is installed.

       conflicts
           Example:

             Data::Dumper: 0
             File::Find: 1.03

           A YAML mapping <http://yaml.org/spec/history/2002-10-31.html#syntax-mapping>
           indicating the Perl modules that cannot be installed while this distribution is
           installed.  This is a pretty uncommon situation.

       dynamic_config
           Example: 0

           A boolean flag indicating whether a Build.PL or Makefile.PL (or similar) must be
           executed, or whether this module can be built, tested and installed solely from
           consulting its metadata file.  The main reason to set this to a true value if that
           your module performs some dynamic configuration (asking questions, sensing the
           environment, etc.) as part of its build/install process.

           Currently Module::Build doesn't actually do anything with this flag - it's probably
           going to be up to higher-level tools like CPAN.pm to do something useful with it.  It
           can potentially bring lots of security, packaging, and convenience improvements.

       generated_by
           Example: "Module::Build version 0.16"

           Indicates the tool that was used to create this META.yml file.  It's good form to
           include both the name of the tool and its version, but this field is essentially
           opaque, at least for the moment.

Related Projects

       DOAP
           An RDF vocabulary to describe software projects. <http://usefulinc.com/doap>.

History

       •   March 14, 2003 (Pi day) - created version 1.0 of this document.

       •   May 8, 2003 - added the "dynamic_config" field, which was missing from the initial
           version.