Plone Strategic Summit: Improve releasing procedures for add-ons

I have been suggested as a "champion" at the Plone Strategic Summit on this task:

# Improve release procedures for add-ons on document a release process, and create release tools for packaging and uploading products from the command line.

This is great, because I have been working a lot in this area in the past month and I think I have a precise idea on what should be done in the Plone community to improve add-ons products visibility and releasing process. I am going to expose here the steps I think we should take, and how to do them, so people can give some feedbacks. Most of them were already explained on this blog on several entries.

PyPI vs

The Cheeseshop (PyPI) is now playing an important role in Plone development. Everytime a Plone 3 application is built somewhere in the world, the Cheeseshop is serving hundreds of tarballs and eggs. Since Zope and Plone has been eggified, and since zc.buildout has been used as the standard way to build a Plone application, Plone developers are releasing all their eggs at PyPI.

This releasing process is really convenient, as a package can be uploaded, and shout out in just one command:
$ python register sdist bdist_egg upload

And an alias can make it even simpler:
$ python release

The problem is that many add-on products pages that used to be up-to-date are not upgraded anymore. So Basically, Software Center is dying because of the actual releasing process of eggs..

The SPOF problem

Another issue with the PyPI-centralized development process is that it becomes a Single Point of Failure. In other words, if PyPI is down, all the buildouts out there are stocked, unless you have a up-to date egg cache on your side.

PyPI though, together with distutils, was thaught as a distributed system: you can theorically call register and upload commands to any server that implements the PyPI Apis. But there are no other PyPI-like server yet in the community. The PyPI code is open source for sure, and anyone could take it and run his own PyPI...

PloneSoftwareCenter features

Another risk we have with a PyPI-centric approach is loosing the features that PSC provides at Those are great, and should be used by all add-ons out there. Milestones, bug tracker, etc.. Everything is provided at for someone to promote and work with his product.

The solution we should take

To avoid the problems mentioned, we need to:
- make PloneSoftwareCenter, therefore, PyPI-compatible - make distutils command-line tools able to interact with several PyPI-compatible servers, besides the official one - provide a simple guideline for the Plone community to work with these tools

The steps


Sidnei has created 2 years ago a branch for PSC with an experimental PyPI support. I have taken this work and continued it on a branch that is almost finished. My goal is to finish it at the Paris Sprint, so PSC will be fully PyPI-compliant. I will soon blog on this to describe the work.

.pypirc and distutils

In order to be able to interact with several PyPI-like server, the .pypirc file need to evolve. I made a patch and a proposal (see: I will try to push in the next Python Bug Day in two weeks, so it is integrated in Python 2.6. If it is accepted, I will release a library that implements the same patch, but for Python 2.4 and 2.5, through specific setuptools commands.


From there, I guess a guideline can be written, explaining :
- how to create a Plone 3 package (through skeletons) - how to release it to both PyPI and

Another point of interest will be to explain how to deal with several egg servers in a buildout.

Proposed calendar

  • Mid-March : provide a package to handle the new .pypirc format
  • End of March : submit the guideline, based on the PSC current branch, and a public instance of the new PSC so people can try it.
  • End of April : finalize PSC PyPI support at the Paris Sprint, together with Alex Clark, so it is available to when it goes Plone 3
  • After that: submit a guideline on how Plone companies can use PSC to create a private PSC, and work together with PyPI, and their own PSC, in a buildout environment

I have also proposed an OSCON topic on this, in Portland, in July. So if my talk is accepted, this can be a good place to promote's Plone Software Center.

Comments !