Provided by: perl-doc_5.36.0-9ubuntu1.1_all bug

NAME

       CPAN::Meta - the distribution metadata for a CPAN dist

VERSION

       version 2.150010

SYNOPSIS

           use v5.10;
           use strict;
           use warnings;
           use CPAN::Meta;
           use Module::Load;

           my $meta = CPAN::Meta->load_file('META.json');

           printf "testing requirements for %s version %s\n",
           $meta->name,
           $meta->version;

           my $prereqs = $meta->effective_prereqs;

           for my $phase ( qw/configure runtime build test/ ) {
               say "Requirements for $phase:";
               my $reqs = $prereqs->requirements_for($phase, "requires");
               for my $module ( sort $reqs->required_modules ) {
                   my $status;
                   if ( eval { load $module unless $module eq 'perl'; 1 } ) {
                       my $version = $module eq 'perl' ? $] : $module->VERSION;
                       $status = $reqs->accepts_module($module, $version)
                               ? "$version ok" : "$version not ok";
                   } else {
                       $status = "missing"
                   };
                   say "  $module ($status)";
               }
           }

DESCRIPTION

       Software distributions released to the CPAN include a META.json or, for older
       distributions, META.yml, which describes the distribution, its contents, and the
       requirements for building and installing the distribution.  The data structure stored in
       the META.json file is described in CPAN::Meta::Spec.

       CPAN::Meta provides a simple class to represent this distribution metadata (or distmeta),
       along with some helpful methods for interrogating that data.

       The documentation below is only for the methods of the CPAN::Meta object.  For information
       on the meaning of individual fields, consult the spec.

METHODS

   new
         my $meta = CPAN::Meta->new($distmeta_struct, \%options);

       Returns a valid CPAN::Meta object or dies if the supplied metadata hash reference fails to
       validate.  Older-format metadata will be up-converted to version 2 if they validate
       against the original stated specification.

       It takes an optional hashref of options. Valid options include:

       •   lazy_validation -- if true, new will attempt to convert the given metadata to version
           2 before attempting to validate it.  This means than any fixable errors will be
           handled by CPAN::Meta::Converter before validation.  (Note that this might result in
           invalid optional data being silently dropped.)  The default is false.

   create
         my $meta = CPAN::Meta->create($distmeta_struct, \%options);

       This is same as "new()", except that "generated_by" and "meta-spec" fields will be
       generated if not provided.  This means the metadata structure is assumed to otherwise
       follow the latest CPAN::Meta::Spec.

   load_file
         my $meta = CPAN::Meta->load_file($distmeta_file, \%options);

       Given a pathname to a file containing metadata, this deserializes the file according to
       its file suffix and constructs a new "CPAN::Meta" object, just like "new()".  It will die
       if the deserialized version fails to validate against its stated specification version.

       It takes the same options as "new()" but "lazy_validation" defaults to true.

   load_yaml_string
         my $meta = CPAN::Meta->load_yaml_string($yaml, \%options);

       This method returns a new CPAN::Meta object using the first document in the given YAML
       string.  In other respects it is identical to "load_file()".

   load_json_string
         my $meta = CPAN::Meta->load_json_string($json, \%options);

       This method returns a new CPAN::Meta object using the structure represented by the given
       JSON string.  In other respects it is identical to "load_file()".

   load_string
         my $meta = CPAN::Meta->load_string($string, \%options);

       If you don't know if a string contains YAML or JSON, this method will use
       Parse::CPAN::Meta to guess.  In other respects it is identical to "load_file()".

   save
         $meta->save($distmeta_file, \%options);

       Serializes the object as JSON and writes it to the given file.  The only valid option is
       "version", which defaults to '2'. On Perl 5.8.1 or later, the file is saved with UTF-8
       encoding.

       For "version" 2 (or higher), the filename should end in '.json'.  JSON::PP is the default
       JSON backend. Using another JSON backend requires JSON 2.5 or later and you must set the
       $ENV{PERL_JSON_BACKEND} to a supported alternate backend like JSON::XS.

       For "version" less than 2, the filename should end in '.yml'.  CPAN::Meta::Converter is
       used to generate an older metadata structure, which is serialized to YAML.
       CPAN::Meta::YAML is the default YAML backend.  You may set the $ENV{PERL_YAML_BACKEND} to
       a supported alternative backend, though this is not recommended due to subtle
       incompatibilities between YAML parsers on CPAN.

   meta_spec_version
       This method returns the version part of the "meta_spec" entry in the distmeta structure.
       It is equivalent to:

         $meta->meta_spec->{version};

   effective_prereqs
         my $prereqs = $meta->effective_prereqs;

         my $prereqs = $meta->effective_prereqs( \@feature_identifiers );

       This method returns a CPAN::Meta::Prereqs object describing all the prereqs for the
       distribution.  If an arrayref of feature identifiers is given, the prereqs for the
       identified features are merged together with the distribution's core prereqs before the
       CPAN::Meta::Prereqs object is returned.

   should_index_file
         ... if $meta->should_index_file( $filename );

       This method returns true if the given file should be indexed.  It decides this by checking
       the "file" and "directory" keys in the "no_index" property of the distmeta structure. Note
       that neither the version format nor "release_status" are considered.

       $filename should be given in unix format.

   should_index_package
         ... if $meta->should_index_package( $package );

       This method returns true if the given package should be indexed.  It decides this by
       checking the "package" and "namespace" keys in the "no_index" property of the distmeta
       structure. Note that neither the version format nor "release_status" are considered.

   features
         my @feature_objects = $meta->features;

       This method returns a list of CPAN::Meta::Feature objects, one for each optional feature
       described by the distribution's metadata.

   feature
         my $feature_object = $meta->feature( $identifier );

       This method returns a CPAN::Meta::Feature object for the optional feature with the given
       identifier.  If no feature with that identifier exists, an exception will be raised.

   as_struct
         my $copy = $meta->as_struct( \%options );

       This method returns a deep copy of the object's metadata as an unblessed hash reference.
       It takes an optional hashref of options.  If the hashref contains a "version" argument,
       the copied metadata will be converted to the version of the specification and returned.
       For example:

         my $old_spec = $meta->as_struct( {version => "1.4"} );

   as_string
         my $string = $meta->as_string( \%options );

       This method returns a serialized copy of the object's metadata as a character string.
       (The strings are not UTF-8 encoded.)  It takes an optional hashref of options.  If the
       hashref contains a "version" argument, the copied metadata will be converted to the
       version of the specification and returned.  For example:

         my $string = $meta->as_string( {version => "1.4"} );

       For "version" greater than or equal to 2, the string will be serialized as JSON.  For
       "version" less than 2, the string will be serialized as YAML.  In both cases, the same
       rules are followed as in the "save()" method for choosing a serialization backend.

       The serialized structure will include a "x_serialization_backend" entry giving the package
       and version used to serialize.  Any existing key in the given $meta object will be
       clobbered.

STRING DATA

       The following methods return a single value, which is the value for the corresponding
       entry in the distmeta structure.  Values should be either undef or strings.

       •   abstract

       •   description

       •   dynamic_config

       •   generated_by

       •   name

       •   release_status

       •   version

LIST DATA

       These methods return lists of string values, which might be represented in the distmeta
       structure as arrayrefs or scalars:

       •   authors

       •   keywords

       •   licenses

       The "authors" and "licenses" methods may also be called as "author" and "license",
       respectively, to match the field name in the distmeta structure.

MAP DATA

       These readers return hashrefs of arbitrary unblessed data structures, each described more
       fully in the specification:

       •   meta_spec

       •   resources

       •   provides

       •   no_index

       •   prereqs

       •   optional_features

CUSTOM DATA

       A list of custom keys are available from the "custom_keys" method and particular keys may
       be retrieved with the "custom" method.

         say $meta->custom($_) for $meta->custom_keys;

       If a custom key refers to a data structure, a deep clone is returned.

BUGS

       Please report any bugs or feature using the CPAN Request Tracker.  Bugs can be submitted
       through the web interface at <http://rt.cpan.org/Dist/Display.html?Queue=CPAN-Meta>

       When submitting a bug or request, please include a test-file or a patch to an existing
       test-file that illustrates the bug or desired feature.

SEE ALSO

       •   CPAN::Meta::Converter

       •   CPAN::Meta::Validator

SUPPORT

   Bugs / Feature Requests
       Please report any bugs or feature requests through the issue tracker at
       <https://github.com/Perl-Toolchain-Gang/CPAN-Meta/issues>.  You will be notified
       automatically of any progress on your issue.

   Source Code
       This is open source software.  The code repository is available for public review and
       contribution under the terms of the license.

       <https://github.com/Perl-Toolchain-Gang/CPAN-Meta>

         git clone https://github.com/Perl-Toolchain-Gang/CPAN-Meta.git

AUTHORS

       •   David Golden <dagolden@cpan.org>

       •   Ricardo Signes <rjbs@cpan.org>

       •   Adam Kennedy <adamk@cpan.org>

CONTRIBUTORS

       •   Ansgar Burchardt <ansgar@cpan.org>

       •   Avar Arnfjord Bjarmason <avar@cpan.org>

       •   Benjamin Noggle <agwind@users.noreply.github.com>

       •   Christopher J. Madsen <cjm@cpan.org>

       •   Chuck Adams <cja987@gmail.com>

       •   Cory G Watson <gphat@cpan.org>

       •   Damyan Ivanov <dam@cpan.org>

       •   David Golden <xdg@xdg.me>

       •   Eric Wilhelm <ewilhelm@cpan.org>

       •   Graham Knop <haarg@haarg.org>

       •   Gregor Hermann <gregoa@debian.org>

       •   Karen Etheridge <ether@cpan.org>

       •   Kenichi Ishigaki <ishigaki@cpan.org>

       •   Kent Fredric <kentfredric@gmail.com>

       •   Ken Williams <kwilliams@cpan.org>

       •   Lars Dieckow <daxim@cpan.org>

       •   Leon Timmermans <leont@cpan.org>

       •   majensen <maj@fortinbras.us>

       •   Mark Fowler <markf@cpan.org>

       •   Matt S Trout <mst@shadowcat.co.uk>

       •   Michael G. Schwern <mschwern@cpan.org>

       •   Mohammad S Anwar <mohammad.anwar@yahoo.com>

       •   mohawk2 <mohawk2@users.noreply.github.com>

       •   moznion <moznion@gmail.com>

       •   Niko Tyni <ntyni@debian.org>

       •   Olaf Alders <olaf@wundersolutions.com>

       •   Olivier Mengué <dolmen@cpan.org>

       •   Randy Sims <randys@thepierianspring.org>

       •   Tomohiro Hosaka <bokutin@bokut.in>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2010 by David Golden, Ricardo Signes, Adam Kennedy and
       Contributors.

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