Posts Tagged With 'python'

Experimental Virtual Machines

Written by Barry Warsaw in technology on Mon 07 June 2010. Tags: canonical, python, ubuntu,

I'm doing some work these days on trying to get Python 2.7 as the default Python in the next version of Ubuntu, Maverick Meerkat (10.10). This work will occasionally require me to break my machine by installing experimental packages. That's a good and useful thing because I want to test various potentially disruptive changes before I think about unleashing them on the world. This is where virtual machines really shine!

To be efficient, I need a really fast turnaround from known good state, to broken state, back to known good state. In the past, I've used VMware Fusion on my Mac to create a VM, then take a live snapshot of the disk before making my changes. It was really easy then to revert to the last known good snapshot, try something else and iterate.

But lately Fusion has sprouted a nasty habit of freezing the host OS, such that a hard reboot is necessary. This will inevitably cause havoc on the host, by losing settings, trashing mail, corrupting VMs, etc. VMware can't reproduce the problem but it happens every time to me, and it hurts, so I'm not doing that any more :).

Back to my Lucid host and libvirt/kvm and the sanctuary of FLOSS. It's really easy to create new VMs, and there are several ways of doing it, from virt-manager to vmbuilder to straight up kvm (thanks Colin for some recipes). The problem is that none of these are exactly fast to go from bare metal to working Maverick VM with all the known good extras I need (like openssh-server and bzr, plus my comfortable development environment).

I didn't find a really good fit for vmbuilder or the kvm commands, and I'm not smart enough to use the libvirt command line tools, but I think …

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From Python package to Ubuntu package in 3-ish easy steps

Written by Barry Warsaw in technology on Mon 24 May 2010. Tags: canonical, ubuntu, debian, python, packaging,

My friend Tim is working on a very cool Bazaar-backed wiki project and he asked me to package it up for Ubuntu. I'm getting pretty good at packaging Python projects, but I always like the practice because each time it gets a little smoother. This one I managed to package in about 10 minutes so I thought I'd outline the very easy process.

First of all, you want to have a good, and if you like to cargo cult, you can start with this one. I highly recommend using Distribute instead of setuptools, and in fact the former is what Ubuntu gives you by default. I really like adding the which gives you nice features like being able to do python test and many other things. See lines 18 and 19 in the above referenced file.

The next thing you'll want is Andrew Straw's fine stdeb package, which you can get on Ubuntu with sudo apt-get install python-stdeb. This package is going to bootstrap your debian/ directory from your file. It's not perfectly suited to the task (yet, Andrew assures me :), but we can make it work!

These days, I host all of my packages in Bazaar on Launchpad, which is going to make some of the following steps really easy. If you use a different hosting site or a different version control system, you will have to build your Ubuntu package using more traditional means. That's okay, once you have your debian/ directory, it'll be fairly easy (but not as easy as described here). If you do use Bazaar, you'll just want to make sure you have the bzr-builddeb plugin. Just do sudo apt-get install bzr-builddeb on Ubuntu and you should get everything you need.

Okay, so now you …

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