May 16, 2013
Due to popular demand I moved debian apt and python-apt from bzr to git today. Moving was pretty painless:
$ git init
$ bzr fast-export --export-marks=marks.bzr -b debian/sid /path/to/debian-sid | git fast-import --export-marks=marks.git
And then a fast-import for the debian-wheezy and debian-experimental branches too. Then a
$ git gc --aggressive
(thanks to Guillem Jover for pointing this out) and that was it.
The branches are available at:
April 30, 2013
For a project of mine I created a small app based on webkitgtk that talks to a SSL server.
And I almost forgot about the libsoup default behavior for SSL certificates checking. By default libsoup and therefore webkitgtk will not do any SSL certificate checks. You need to put something like the following snippet into your code (adjust for your language of choice):
from gi.repository import WebKit
session = WebKit.get_default_session()
If you don’t do this it will accept any certificate (including self-signed ones).
This is documented behavior in libsoup and they don’t want to change it for compatiblity reasons in libsoup. But for webkit its unexpected behavior (at least to me) and I hope the webkitgtk developers will consider changing this default in webkit. I filed a bug about it. So if you use webkitgtk and SSL, remember to set the above property.
April 18, 2013
I use the PassHash firefox extension to generate site-specific strong passwords. The idea behind the extension is that a master password and a siteTag (e.g. the domain name) is used to generate a sha1 hash. This hash is used as the password for the website. In python its essentially this code:
h = hmac.new(master_pass, site_tag, hashlib.sha1)
I want a commandline utility that can output me PassHash compatible hashes when I use w3m (or if the extension stops working for some reason).
To my delight I discovered that the upstream git repNice and hard to brute-force.o of PassHash already has a python helper to generate passhash compatible password. I added some tweaks to add pythons argparse  and now I’m really happy with it:
$ ./tools/passhash.py --hash-size 14 slashdot.org
Please enter the master key:
Hard to brute-force and matches what the extension generates.
April 11, 2013
I uploaded squid-deb-proxy into Debian unstable today and its in the NEW queue. I created it back in the days of Ubuntu 10.04 and some people voiced interest in having it in Debian as well so I spend a bit of time to get it customized for Debian.
Squid-deb-proxy uses the well known squid proxy with a custom configuration to cache deb package and Indexfiles (like Packages.gz) that will allow caching from the default archives and mirrors and reject anything else by default.
The basic philosophy is that “it just works”. You run on your server:
root@server# apt-get install squid-deb-proxy
and on your clients:
root@client# apt-get install squid-deb-proxy-client
and that’s it. It does not require any fiddling with configuration (unless you want to ). The default will let you connect to .debian.org and nothing else.
The server will announce itself via avahi as _apt_proxy._tcp and the
client will hook into apt to use Acquire::http::ProxyAutoDetect. The
client is useful for other servers that announce themself via avahi.
Packaging was a bit more work than anticipated because there is a bit of setup and teardown work in the initscript. For Debian as sysvinit script was needed, Ubuntu uses upstart so it took a bit of refactoring to extract the code into a common helper.
If you want to try it now, its available via:
$ bzr branch lp:squid-deb-proxy
$ cd squid-deb-proxy
and in unstable once it leaves the NEW queue.
March 27, 2013
A while ago I played with sqlite. Its pretty awesome. When using the full text search (fts) extension it also provides super fast full text searching. One of the things I was missing (compared to other engines) is the similar text suggestion (“Did you mean?”) support. Fortunately this is relatively easy to add via the fts4aux virtual table that sqlite supports.
I pushed a full example of to https://github.com/mvo5/sqlite-fts-did-you-mean. The way it works is that you build a set of similar words and use that to query for the “term” value from the fts4aux table.
Here is the output from the example:
$ ./fts_did_you_mean.py aptx
Did you mean:
apex (rank: 2)
apt (rank: 1)
March 22, 2013
I wrote gdebi a long time ago to make it really easy to install .deb package with proper dependency resolution from the commandline and via a gtk (and kde) UI. But another neat (but not very well known) feature of the gdebi-core cli tool is to install the build-dependencies of a debian source package. If you run:
$ gdebi debian/control
in a unpacked debian source package it will check for missing build-dependencies and offer to install them.
March 16, 2013
There is a new 0.80~exp2 version of unattended-upgrades available. This would normally be fine for debian/sid but because of the freeze I decided to put it into experimental. Some nice features like adding a “–verbose” mode that shows the actual dpkg output when
running and codename based matching plus some nice fixes from Brian Murray (thanks!).
The codename based matching is interessting as it allows writing a matcher like “n=wheezy” (or more verbose “codename=wheezy”) in the config file. You can use “apt-cache policy” (without further arguments) to see what origins are available.
Enjoy and let me know if you find any issues issues!
January 8, 2013
I got a Music Shield from Seeedstudio a while ago. Its fun to play with but the example source did not quite work for me. So I ported it over to the the new SD library from arduino 1.0 and published a google plus post about it. Some people asked me about the source so I pushed the result to launchpad and github. I also filed a upstream request to include it.
January 5, 2013
If you tried to reach me via my ubuntu.com mail in the last couple of days you got a 550 error. There seems to be some misconfiguration on the ubuntu.com mailserver, I hope it gets fixed soon. You can use my mvo at debian.org in the meantime.
August 16, 2011
I created a small extension for sqlite3 today to allow order by debian version easily. This allows writing:
SELECT * FROM packages ORDER BY version COLLAT debversion_compare;
And it will do the right ordering. Its available on launchpad.