Trac(k)ing svn repositories

I had been dragging my feet for a while, hoping the Simile subversion repository would get a nice web based Trac timeline over commits and change sets, if I asked nicely and waited patiently. That very often helps with open source projects (Edit: this time too, eventually), but not always.

Last weekend I took to setting up a local mirror of the repository to set up my own, local, Trac, just to get that timeline/changeset browser combination. I find it indispensable for software development with more than one developer (and a very useful tool, even when you're on your own).

Thanks to SVK (a rather mature perl concoction running atop the subversion filesystem and remote access layers -- see the svk book for more info, for instance), it is actually rather comfortable to set up your local subversion mirror of a remote repository, whether your own or someone else's. Even saves you some disk compared to a common subversion repository.

Anyway, to do that I first created a vc user (for "version control", for lack of imagination) as I wanted to avoid mixing up my own user's SVK depot (kept in ~/.svk) with the repository I wanted to get Trac coverage for, in System Preferences. Running as that user, here are the steps I needed to take to get this running on my (fink enabled) macbook:

# installing the packages:
sudo fink install trac-py24
sudo fink install svk

# setting up the local repository mirror and syncing up:
svk mirror https://simile.mit.edu/repository //mirror/simile
svk sync //mirror/simile

# pointing Trac at it
mkdir ~/trac
trac-admin ~/trac/simile initenv

Then I got to answer to some questions; name my Trac instance Simile, point it to the repository root /Users/vc/.svk/local, say that it is an svn repository and get pointed to the config file ~/trac/simile/conf/trac.ini, which needed some editing.

If you want full commit messages in the timeline (I do), make sure you keep wiki_format_messages in the [changeset] section and changeset_long_messages under [timeline] both set to true. You'd think these options are orthogonal from their names, but they are not; the latter is happily ignored if you turn off wikiml. So even if, like in my case, commit messages aren't wikiml markup tied to the wiki and issue tracker inside this Trac instance, it's either pretend it is, or get truncated commit messages.

Starting it is done with tracd --port 8000 ~/trac/simile (or something more permanent, by way of Apache or similar), and you can browse at http://localhost:8000/, once come this far. If you want some more linkage and less round trips between views, feel free to tuck in my Trac Timeline and Trac Changeset improver Greasemonkey scripts crafted for this particular purpose.

Does anyone know of any Trac plugins to export changeset data as JSON / JSONP? I have some plans for equipping the setup with a facet browser and some commit message searchability, and it would be a great help if I didn't have to write them myself. Even better would be getting that installed at DevjaVu, so lots of other people could benefit from the same hack. Including my own repositories. (Which I could arguably mirror, but where is the fun or elegance in that?)