rcaputo / app-bundlefly Goto Github PK

--- WTF?!

I'm dissatisfied with the way CPAN tools install modules, especially
when they install several modules at once.

Modules in autobundle snapshots are installed alphabetically.
Dependencies are prepended as needed, and then they are installed
again later when they appear in the alphabet.

Distributions with a lot of dependencies tend to have the same issue
on a smaller scale.  Common dependencies such as Test::More may be
prepended and installed multiple times.

Yes, confirmations can be made automatic.

Yes, automatic confirmations suck less.

But redundantly installing modules, perhaps many times, still sucks.

--- So What?

Perlbrew lowers the effort to install new versions of Perl.  This is
awesome, and it's all fun and games, until one realizes that each new
Perl instance is missing all those necessary modules.

Autobundle snapshots reduce the effort needed to install a suite of
modules into a new Perl instance.  Create an autobundle snapshot from
one Perl instance, and install them into another.

These tools reduce the bletcherous redundancy inherent in autobundle
installs.  The process is greatly improved.

--- What You Get

This project includes two utilities to stop the sucking altogether.

"smartcpan" installs one or more modules and their dependencies so
that the dependencies come before the dependants.  This minimizes
(often eliminates) "prepend them to the queue" prompts and redundant
installations.

"smartbundle" does the same for all the modules in an autobundle
snapshot.

--- How It Works

CPANDB lets us quickly find the distributions for each module to
install.

It uses Graph::Directed to build dependency graphs for each module.
We subvert CPANDB to build a combined dependency graph for all
requested modules.

The graph is iterated through from successorless vertices
(distributions) up to the requested distributions.  Successorless
vertices are removed from the graph after each iteration.  This
continues until the entire graph has been installed and deleted.

The graph is based on distributions, but CPAN tools install modules.
CPANDB is used again to install a module for each distribution.

--- Troublesome

Log::Log4perl installs fine, but cpan doesn't seem to see it.  Every
time smartbundle is run, it installs Log::Log4perl again.  So much for
eliminating redundancy, eh?