[Melbourne-pm] caching CPAN dist files

[Jacinta Richardson]

Malcolm Herbert wrote:
> I'm in the process of putting together a project that I'm expecting to
> use a fair number of CPAN modules directly rather than using the system
> native packages of them, for portability.  I have a few development and
> test instances and a few instances in production.  I'd like to use CPAN
> to manage the modules installed on each, however I want to make sure
> that they stay in sync with each other and avoid potential dependency
> issues should my development and production environments drift too far
> apart.  Ideally I'd like to use the CPAN tools to update the production
> environment only from the set of modules I've collected and tested on my
> dev/test hosts.

An alternative solution is as follows, although this can be overkill.

CPAN::Mini allows you to create a mirror of CPAN. The latest and 
greatest of everything right now. App::cpanminus is CPAN::Mini aware, so 
you can tell it to install from your mirror rather than CPAN directly. 
Then you can use local::lib to refer to handle having everything 
installed into a local location (App::cpanminus is local::lib aware too).

One not-so-obvious gotcha is that if you're using perlbrew as well, then 
you need to install App::cpanminus for each new version of Perl you 
install with perlbrew. I'm not exactly sure why, but App::cpanminus 
forms an opinion on your version of Perl when you install it; and even 
if you then invoke it later with a different (younger) version of Perl 
in your path, it'll still baulk on version dependencies.

All the best,

Jacinta