NAME

CPAN::FindDependencies - find dependencies for modules on the CPAN

SYNOPSIS

use CPAN::FindDependencies;
my @dependencies = CPAN::FindDependencies::finddeps("CPAN");
foreach my $dep (@dependencies) {
    print ' ' x $dep->depth();
    print $dep->name().' ('.$dep->distribution().")\n";
}

HOW IT WORKS

The module uses the CPAN packages index to map modules to distributions and vice versa, and then fetches distributions' META.yml files from http://search.cpan.org/ to determine pre-requisites. This means that a working interwebnet connection is required.

FUNCTIONS

There is just one function, which is not exported by default although you can make that happen in the usual fashion.

finddeps

Takes a single compulsory parameter, the name of a module (ie Some::Module); and the following optional named parameters:

nowarnings

Warnings about modules where we can't find their META.yml, and so can't divine their pre-requisites, will be suppressed;

fatalerrors

Failure to get a module's dependencies will be a fatal error instead of merely emitting a warning;

perl

Use this version of perl to figure out what's in core. If not specified, it defaults to 5.005. Three part version numbers (eg 5.8.8) are supported but discouraged.

02packages

The location of CPAN.pm's 02packages.details.txt.gz file as a URL. To specify a local file, say something like file:///home/me/minicpan/02packages.details.txt.gz. This defaults to fetching it from a public CPAN mirror. The file is fetched once, when the module loads.

cachedir

A directory to use for caching. It defaults to no caching. Even if caching is turned on, this is only for META.yml files. 02packages is not cached. (This isn't yet implemented)

It returns a list of CPAN::FindDependencies::Dependency objects, whose useful methods are:

name

The module's name

distribution

The distribution containing this module

depth

How deep in the dependency tree this module is

BUGS/WARNINGS/LIMITATIONS

You must have web access to http://search.cpan.org/ and (unless you tell it where else to look for the index) http://www.cpan.org/. If any META.yml files are missing, the distribution's dependencies will not be found and a warning will be spat out.

Startup can be slow, especially if it needs to fetch the index from the interweb.

FEEDBACK

I welcome feedback about my code, including constructive criticism and bug reports. The best bug reports include files that I can add to the test suite, which fail with the current code in CVS and will pass once I've fixed the bug

Feature requests are far more likely to get implemented if you submit a patch yourself.

CVS

http://drhyde.cvs.sourceforge.net/drhyde/perlmodules/CPAN-FindDependencies/

SEE ALSO

CPAN

http://cpandeps.cantrell.org.uk/

http://search.cpan.org

AUTHOR, LICENCE and COPYRIGHT

Copyright 2007 David Cantrell <david@cantrell.org.uk>

This module is free-as-in-speech software, and may be used, distributed, and modified under the same terms as Perl itself.

CONSPIRACY

This module is also free-as-in-mason software.