NAME
Pinto::Manual::Introduction - Why Pinto exists
VERSION
version 0.062
GOALS
Pinto has two primary goals. First, Pinto seeks to address the problem of instability in the CPAN mirrors. Distribution archives are constantly added and removed from the CPAN, so if you use it to build a system or application, you may not get the same result twice. Second, Pinto seeks to encourage developers to use the CPAN toolchain for building, testing, and dependency management of their own local software, even if they never plan to release it to the CPAN.
Pinto accomplishes these goals by providing tools for creating and managing your own custom repositories of distribution archives. These repositories can contain any distribution archives you like, and can be used with the standard CPAN toolchain. The tools also support various operations that enable you to deal with common problems that arise during the development process.
PRIOR ART
The idea of a custom repository is not new. Randal Schwartz presented the idea back in 2002. Subsequently, modules like CPAN::Site and CPAN::Mini were released. More recently, OrePAN and MyCPAN::App::DPAN have emerged as well.
Over the last few years, I personally used various combinations of those modules to create custom repositories at several organizations. But they always required some wrapping and/or glue to make them really usable in the development process. And none of them seemed to be designed for extension.
I wanted a suite of tools that would work out-of-the-box, and would accommodate a fairly wide range of use cases. Hence, Pinto was born.
COMPONENTS
The Pinto suite consists of several libraries and applications. Each component ships in a separate distribution, so you don't have to install the whole kit if you're only going to use a subset of the Pinto suite. However, you can install Task::Pinto if you'd like to get everything in one shot.
pinto
pinto is a command line application for creating and managing a Pinto repository. It is just the front-end, so you'll also need to install one or both of the back-ends (see "Pinto" and "Pinto::Remote" below). The back-ends ship separately from pinto, so you can decide which one you need.
pintod
pintod provides a web service interface to your Pinto repository. This allows multiple (possibly remote) developers to manage a central repository. pintod also functions as the back end server for installer clients like cpan, cpanp, and cpanm.
Pinto
Pinto is the back-end library for working with a local repository. If you need to create repositories or manage repositories on the local disk, then you should install Pinto.
Pinto::Remote
Pinto::Remote is the back-end for working with a remote repository. If you already have a repository on a remote host that is running pintod then you should install Pinto::Remote.
TERMINOLOGY
Some of the terminology related to the CPAN is overloaded, which can lead to some confusion. So I'll try to define some of the key terms that I use throughout the documentation and the code.
Archive
An "archive" is the file that developers ship, which contains all their application/library code, test cases, build scripts etc. Conversely, the archive is the file that users must fetch to install the application/library. Sometimes I also refer to these as "distributions".
Package
A "package" is something inside a distribution archive that provides some unit of functionality. In Perl, packages are declared with the package keyword. Some folks call these "modules" but I try to avoid that term because it is frequently misused.
Prerequisite
A "prerequisite" is a package that must be installed for the sake of another distribution archive. Sometimes I call these "dependencies". Pinto does not currently distinguish between different flavors of prerequisites, such as "build-time" or "run-time" prerequisites.
CONCEPTS
Stack
All CPAN-like repositories have an index which maps the latest version of each package to the archive that contains it. Usually, there is only one such index. But with Pinto, there can be many indexes. Each of these indexes is called a "stack". This allows you to create different stacks of dependencies within a single repository. So you could have a "development" stack and a "production" stack. Whenever you add a distribution or upgrade a prerequisite, it only affects one stack.
Pin
Only one version of a package can exist within a stack. So when you upgrade a package on stack, the newer version replaces the older one. But sometimes, you discover that a newer version of package is incompatible with your application, and you want to stay with the older version until you have an opportunity to fix the problem. In those situations, Pinto allows you to "pin" a particular version of a package to the stack. This prevents the package from being upgraded (either directly or as a prerequisite for some other package).
WHY IS IT CALLED PINTO
Pinto is a name that I sometimes use for my son Wesley (as in "pinto bean"). Daddy loves you, Wes!
SEE ALSO
- Pinto::Manual::Tutorial
-
Presents a narrative explanation of how to use Pinto.
- Pinto::Manual::QuickStart
-
Presents a condensed summary of pinto commands.
AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
COPYRIGHT AND LICENSE
This software is copyright (c) 2011 by Imaginative Software Systems.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.