| CPAN::Meta - the distribution metadata for a CPAN dist |
CPAN::Meta - the distribution metadata for a CPAN dist
version 2.150010
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)";
}
}
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 the CPAN::Meta::Spec manpage.
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.
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:
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 the CPAN::Meta::Spec manpage.
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.
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().
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().
my $meta = CPAN::Meta->load_string($string, \%options);
If you don't know if a string contains YAML or JSON, this method will use
the Parse::CPAN::Meta manpage to guess. In other respects it is identical to
load_file().
$meta->save($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'. the JSON::PP manpage
is the default JSON backend. Using another JSON backend requires the JSON manpage 2.5 or
later and you must set the $ENV{PERL_JSON_BACKEND} to a supported alternate
backend like the JSON::XS manpage.
For version less than 2, the filename should end in '.yml'.
the CPAN::Meta::Converter manpage 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.
This method returns the version part of the meta_spec entry in the distmeta
structure. It is equivalent to:
$meta->meta_spec->{version};
my $prereqs = $meta->effective_prereqs;
my $prereqs = $meta->effective_prereqs( \@feature_identifiers );
This method returns a the CPAN::Meta::Prereqs manpage 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.
... 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.
... 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.
my @feature_objects = $meta->features;
This method returns a list of the CPAN::Meta::Feature manpage objects, one for each optional feature described by the distribution's metadata.
my $feature_object = $meta->feature( $identifier );
This method returns a the CPAN::Meta::Feature manpage object for the optional feature with the given identifier. If no feature with that identifier exists, an exception will be raised.
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"} );
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.
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.
These methods return lists of string values, which might be represented in the distmeta structure as arrayrefs or scalars:
The authors and licenses methods may also be called as author and
license, respectively, to match the field name in the distmeta structure.
These readers return hashrefs of arbitrary unblessed data structures, each described more fully in the specification:
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.
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
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.
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.
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
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.
| CPAN::Meta - the distribution metadata for a CPAN dist |