Module::CPANfile(3)

NAME
Module::CPANfile - Parse cpanfile

SYNOPSIS
  use Module::CPANfile;

  my $file = Module::CPANfile->load("cpanfile");
  my $prereqs = $file->prereqs; # CPAN::Meta::Prereqs object

  my @features = $file->features; # CPAN::Meta::Feature objects
  my $merged_prereqs = $file->prereqs_with(@identifiers); # CPAN::Meta::Prereqs

  $file->merge_meta('MYMETA.json');

DESCRIPTION
Module::CPANfile is a tool to handle cpanfile format to load application specific dependencies, not just for CPAN distributions.

METHODS

load
      $file = Module::CPANfile->load;
      $file = Module::CPANfile->load('cpanfile');

    Load and parse a cpanfile. By default it tries to load "cpanfile" in the current directory, unless you pass the path to its argument.

from_prereqs
      $file = Module::CPANfile->from_prereqs({
        runtime => { requires => { DBI => '1.000' } },
      });

    Creates a new Module::CPANfile object from prereqs hash you can get via CPAN::Meta's "prereqs", or CPAN::Meta::Prereqs' "as_string_hash".

      # read MYMETA, then feed the prereqs to create Module::CPANfile
      my $meta = CPAN::Meta->load_file('MYMETA.json');
      my $file = Module::CPANfile->from_prereqs($meta->prereqs);

      # load cpanfile, then recreate it with round-trip
      my $file = Module::CPANfile->load('cpanfile');
      $file = Module::CPANfile->from_prereqs($file->prereq_specs);
                                        # or $file->prereqs->as_string_hash

prereqs
    Returns CPAN::Meta::Prereqs object out of the parsed cpanfile.

prereq_specs
    Returns a hash reference that should be passed to "CPAN::Meta::Prereqs->new".

features
    Returns a list of features available in the cpanfile as CPAN::Meta::Feature.

prereqs_with(@identifiers), effective_prereqs(\@identifiers)
    Returns CPAN::Meta::Prereqs object, with merged prereqs for features identified with the @identifiers.

to_string($include_empty)
      $file->to_string;
      $file->to_string(1);

    Returns a canonical string (code) representation for cpanfile. Useful if you want to convert CPAN::Meta::Prereqs to a new cpanfile.

      # read MYMETA's prereqs and print cpanfile representation of it
      my $meta = CPAN::Meta->load_file('MYMETA.json');
      my $file = Module::CPANfile->from_prereqs($meta->prereqs);
      print $file->to_string;

    By default, it omits the phase where there're no modules registered. If you pass the argument of a true value, it will print them as well.

save
      $file->save('cpanfile');

    Saves the currently loaded prereqs as a new "cpanfile" by calling "to_string". Beware this method will overwrite the existing cpanfile without any warning or backup. Taking a backup or giving warnings to users is a caller's responsibility.

      # Read MYMETA.json and creates a new cpanfile
      my $meta = CPAN::Meta->load_file('MYMETA.json');
      my $file = Module::CPANfile->from_prereqs($meta->prereqs);
      $file->save('cpanfile');

merge_meta
      $file->merge_meta('META.yml');
      $file->merge_meta('MYMETA.json', '2.0');

    Merge the effective prereqs with Meta specification loaded from the given META file, using CPAN::Meta. You can specify the META spec version in the second argument, which defaults to 1.4 in case the given file is YAML, and 2 if it is JSON.

options_for_module
      my $options = $file->options_for_module($module);

    Returns the extra options specified for a given module as a hash reference. Returns "undef" when the given module is not specified in the "cpanfile".

    For example,

      # cpanfile
      requires 'Plack', '1.000',
        dist => "MIYAGAWA/Plack-1.000.tar.gz";

      # ...
      my $file = Module::CPANfile->load;
      my $options = $file->options_for_module('Plack');
      # => { dist => "MIYAGAWA/Plack-1.000.tar.gz" }

AUTHOR
Tatsuhiko Miyagawa

SEE ALSO
cpanfile, CPAN::Meta, CPAN::Meta::Spec