NAME¶
CPAN::Meta - the distribution metadata for a CPAN dist
VERSION¶
version 2.142690
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.
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.
$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.
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.
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>
CONTRIBUTORS¶
- •
- Ansgar Burchardt <ansgar@cpan.org>
- •
- Avar Arnfjord Bjarmason <avar@cpan.org>
- •
- Christopher J. Madsen <cjm@cpan.org>
- •
- Chuck Adams <cja987@gmail.com>
- •
- Cory G Watson <gphat@cpan.org>
- •
- Damyan Ivanov <dam@cpan.org>
- •
- 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>
- •
- 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>
- •
- moznion <moznion@gmail.com>
- •
- Olaf Alders <olaf@wundersolutions.com>
- •
- Olivier Mengue <dolmen@cpan.org>
- •
- Randy Sims <randys@thepierianspring.org>
COPYRIGHT AND LICENSE¶
This software is copyright (c) 2010 by David Golden and Ricardo Signes.
This is free software; you can redistribute it and/or modify it under the same
terms as the Perl 5 programming language system itself.