###################################################################### CPAN::Unwind 0.06 ######################################################################

NAME CPAN::Unwind - Recursively determines dependencies of CPAN modules

SYNOPSIS use CPAN::Unwind;

    my $agent = CPAN::Unwind->new();

    my $resp = $agent->lookup("Log::Log4perl");
    die $resp->message() unless $resp->is_success();

    my $deps = $resp->dependent_versions();

    for my $module (keys %$deps) {
        printf "%30s: %s
", $module, $deps->{$module};
    }
        # Prints:
        #
        #  Test::Harness: 2.03
        #     Test::More: 0.45
        #     File::Spec: 0.82
        # File::Basename: 0
        #           Carp: 0

    print "Installation schedule:
";
    for($resp->schedule()) {
        print "$_
";
    }
        # Installation schedule:
        # Carp
        # File::Basename
        # File::Spec
        # Test::Harness
        # Test::More
        # Log::Log4perl

DESCRIPTION CPAN::Unwind recursively determines dependencies of CPAN modules. It fetches distribution tarballs from CPAN, unpacks them, and runs Module::Depends::Intrusive on them.

SECURITY NOTE: CPAN::Unwind runs all Makefile.PL files (via
"Module::Depends::Intrusive") of modules it finds dependencies on. If
you are concerned that any module in the dependency tree on CPAN isn't
trustworthy, only use it in a secured sandbox.

METHODS CPAN::Unwind supports the following methods:

"my $agent = CPAN::Unwind->new();"
    Create a new dependency agent. The following options are supported:

    "cache"
        Provide your own "Cache::Cache" object (see *Caching*).

    "add"
        Provide additional dependencies that should be part of the
        result:

            CPAN::Unwind->new(add => 
                ["Foo", "Bar" => 0.17,
                 ...
                ]);

        indicates that "Foo" has a dependency on "Bar" 0.17, even if
        it's not listed in "Foo"'s "Makefile.PL". This way, you can fix
        broken Makefile.PL files of some CPAN modules, not listing their
        dependencies correctly.

"$resp = $agent->lookup_single($module_name)"
    Goes to CPAN and fetches the tarball containing the module specified
    in $module_name. After unpacking the tarball, it will use
    Module::Depends::Intrusive to determine the modules it depends on.

    Returns a "CPAN::Unwind::Response" object.

"$resp = $agent->lookup($module_name)"
    Calls "lookup_single" on $module_name recursively, builds a
    dependency tree and returns a "CPAN::Unwind::Response" object
    containing a consolidated dependency tree.

CPAN::Unwind::Response supports the following methods:

"$resp->is_success()"
    Returns true if there's a valid response and no error occurred.

"$resp->message()"
    Returns a response's error message in case "is_success()" returned a
    false value.

"$resp->dependent_versions()"
    Returns a ref to a hash, containing a mapping between names of
    dependent modules and their version numbers:

        { "Test::More"  =>  0.51,
          "List::Utils" =>  0.38,
          ...
        }

"$resp->missing()"
    Similar to "dependent_versions()", but only modules that are
    currently *not* installed are returned.

"$resp->dependents()"
    Returns a ref to a hash, mapping module names to their dependencies.

        { "Net::Amazon"  =>  ["Log::Log4perl", "XML::Simple"],
          "List::Utils"  =>  [],
          ...
        }

    If an entry holds a ref to an empty array, the module doesn't have
    any dependencies.

"$resp->schedule()"
    Returns an installation schedule, a list of module names in the
    correct order without dependency conflicts. Returns "undef" if no
    schedule can be made due to circular dependencies.

Caching To avoid costly downloads, "CPAN::Unwind" will cache dependencies in a Cache::FileCache cache, where they are stored indefinitely. Running it the second time on a module will speed up processing significantly.

Turnkey Scripts "CPAN::Unwind" comes with a ready-to-use script "cpan-unwind", which gets installed in perl's bin path. It is ready to use, just call

    $ cpan-unwind Log::Log4perl

to see which modules "Log::Log4perl" depends on.

"CPAN::Unwind" requires a valid CPAN configuration.

EXAMPLES $ cpan-unwind Net::Amazon Carp Compress::Zlib Data::Dumper Fcntl File::Basename File::Path File::Spec HTML::Tagset IO::Socket MIME::Base64 Socket Test::Harness Test::More Test::Simple Time::HiRes URI XML::NamespaceSupport Digest::base File::Temp HTML::Parser Log::Log4perl Net::FTP XML::SAX XML::Simple Digest::MD5 LWP::UserAgent Net::Amazon

LEGALESE Copyright 2005-2011 by Mike Schilli, all rights reserved. This program is free software, you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR 2005, Mike Schilli [email protected]