April 2017 Archives

Specifying the type of your CPAN dependencies

This is the third article in a series on CPAN distribution metadata. The first article was a general introduction, and the second article looked at dependencies, and in particular the different phases that you can specify dependencies for (configure, build, runtime, test, and develop). In this article, we'll cover the different types of dependencies and how you combine these with the phases (described in the previous article) to specify the dependencies (or prereqs) for your CPAN distribution.

This article is brought to you by MaxMind, a gold Sponsor for this year's Toolchain Summit, being held next month (May) in Lyon, France. The summit is only possible with the support of our sponsors.

The Perl Toolchain Summit Project List

The Perl Toolchain Summit (PTS) is the annual event where we assemble the people who are actively working on the Perl toolchain, and give them 4 days to work together. In this blog post, we'll look at how we decide what everyone will work on, and give you a chance to make suggestions.

This blog post is brought to you by Perl Jobs by Perl Careers, which as well as helping Perl programmers find jobs, supports a number of community events, including the QA Hackathon last year.

Dependency phases in CPAN distribution metadata

In the previous article in this series we gave a general introduction to the distribution metadata which is included in releases as files META.json and/or META.yml. In this article I'll drill into more detail at one critical component of a distribution's metadata: dependencies, also known as prerequisites (usually shortened to "prereqs"). This is how you specify other CPAN modules that your distribution depends on.

This post is brought to you by Booking.com, a platinum sponsor for the Perl Toolchain Summit. Booking.com is one of the largest Perl shops in the world, and so depends heavily on the toolchain. Thank you to Booking.com for supporting the summit.

An introduction to CPAN distribution metadata

All CPAN releases (these days) include a metadata file which has information about the distribution. It can be used by tools like CPAN clients (when installing modules), but it's also helpful for other tool writers, and people analysing the structure of CPAN. The metadata file will be called META.yml or META.json, and recent releases often contain both.

In this blog post we'll introduce some of what's in the files and how they're used by CPAN clients.

This post is brought to you by FastMail, a gold sponsor for this year's Toolchain Summit, which is being held in Lyon, France in May. The summit is only possible with the support of companies like FastMail. We'll be doing a series of toolchain-related blog posts, to thank our sponsors.

About Neil Bowers

user-pic Perl hacker since 1992.