Using Git when developing Plone applications

While I’m enthusiastic about Git, I still have to communicate with Subversion repositories like the Plone Collective. I also like my editor (Emacs) to help me interact with Git. In this blog entry I’ll explain how I setup my work environment.

Choosing a distributed version control system was step one. Step two is incorporating it in my working life. This starts with retrieving and storing the source code for the projects I’m working on.


One of the reasons I chose Git was the “bidirectional flow of changes” that will be necessary. The Git repository on my computer will have to pull in the changes from the Subversion repository. Likewise, I have to make my changes available for others by pushing them back to the central repo.

Git-svn allows me to clone the necessary part of a Subversion repository. For instance, to clone the buildout of project X I can easily do:

git svn clone https://svn..../projectX/buildout -s

This will clone (checkout) the project X buildout. By adding the “-s” parameter I tell Git that the buildout directory has the standard Subversion layout. (In other words: it contains trunk, branches and tags directories.) There is plenty git-svn documentation out there, so I won’t describe it any further here. For more information see for example the documentation I linked to above or blog posts like Howto use Git and svn together and Effectively Using Git With Subversion.


Okay, we’ve got the buildout. Now at Zest we basically have two types of buildout configurations. We either include the products for the policy, theme, et cetera by using the svn:externals property in the src directory, or we include those products by using infrae.subversion.

I haven’t found a proper solution for projects that use the latter approach (other than restructuring the buildout that is). At the moment I just use Subversion instead of Git. However if the project collects all the products with the svn:externals property, there are options…

Personally I use the git-svn-clone-externals script that can be found on GitHub. To be precise, I use the fork by Paul J Stevens. By starting this script in the root directory of the Git repository (in my case the buildout directory) it finds the products in src and clones each of them.

Since I have a couple of buildouts with more than five products as svn:externals, I got tired of manually making sure all changes in them are committed and pushed back to the subversion repository. Therefore I forked the git-svn-clone-externals repository and added two scripts that help me with this. By running the git-svn-externals-check script in the src directory I can be pretty sure everything is back in Subversion so my co-workers can access it.


I use Emacs to code, thus I also wanted to use it to help me with the version control stuff. For Subversion I use psvn.el and I was looking for something similar. I first tried git.el (which comes with Git) because the key bindings were similar. But although it got me started quickly, it didn’t feel quite right. For instance, I could not find a way to work with staged changes. And this is a feature I really started to like and use.

To make a long story short: I switched to Magit for the moment. Although it took me a while to get used to the key bindings, I actually really like it! It allows me to work with Git from Emacs and the command line in a similar fashion. Actions taken in one of them do not get in the way of the other.

I’m not completely settled yet, but I do love working with Git. I hope to be able to use it on more and more projects.