http://www.chrisspen.com/blog knowledge through programming Tue, 27 Jul 2010 18:59:14 +0000 http://backend.userland.com/rss092 en I was researching methods to encrypt USB flash drives, to protect personal data in the event they're lost or stolen, and I found a few good write-ups on the subject using tools available in Ubuntu. Although the current distribution of Gnome includes pretty good support for auto-detecting and prompting for ... http://www.chrisspen.com/blog/ubuntu-flash-drive-encryption-script.html I was researching simple methods for backing up a basic Linux web server, and I found an excellent script that handles files and databases, and also dumps everything to a remote server. I was looking for something a bit less complicated and overkill than Bacula, but more comprehensive than simply ... http://www.chrisspen.com/blog/how-to-remotely-backup-a-web-server-with-no-install.html Rock-paper-scissors is not a complicated game. However, there are some that not only enjoy the game, but take pride in professing skill at it. But is it possible to have skill at rock-paper-scissors? In the real world, where a human plays against a human, "cheating" is relatively easy. A player can ... http://www.chrisspen.com/blog/implementing-a-simple-machine-learning-intelligence-to-play-rock-paper-scissors-in-javascript.html I have some basic Django code that attempts to insert a new record into a PostgreSQL database. It's wrapped in a try/except statement in case a unique constraint is violated, in which case I'll typically ignore it and move on. So the general pattern is: from django.db import IntegrityError import models try: ... http://www.chrisspen.com/blog/handling-postgresql-integrity-errors-in-django.html I've been using MySQL for a while with my pet projects, but recently I've been writing some more complicated queries, and I'm running into a few obnoxious limitations, mostly involving known view performance problems. I've decided to start testing the waters in PostgreSQL, so I tried importing my data into ... http://www.chrisspen.com/blog/enabling-implicit-cast-from-integer-to-boolean-in-postgresql.html It's a trivial fix, and it took them over a month to get around to it (hey, I'm sure they're busy), but Google's App Engine team finally accepted my patch. With that, the development datastore can be specified with a relative path, making app-engine related scripts easier to share with ... http://www.chrisspen.com/blog/google-app-engine-patch-accepted.html I found a convenient method for creating elements with rounded corners and a drop shadow. Previously, I had been using Steffen Rusitschka's ShadedBorder script to accomplish this effect with minimal overhead. While his script is an impressive piece of work, it can be a little slow to render since it ... http://www.chrisspen.com/blog/simple-cross-browser-rounded-corners-with-drop-shadow.html I decided to try my hand at making a Flash game using Actionscript 3. I have mixed feelings towards Adobe technologies, but AS3 is a significant improvement over AS2. The syntax is now much closer to that of Java, with cleaner object-orientation and strict type checking. They also released their ... http://www.chrisspen.com/blog/swarmastica-a-flash-game.html The Problem I recently found myself writing a custom Javascript API to integrate a Flash widget written by an external vendor. I was making the API object oriented, so it could be instantiated and controlled simply like: var myWidget = new FlashWidget() myWidget.doStuff() Things were going well, until I realized I had overlooked a ... http://www.chrisspen.com/blog/how-to-make-a-generic-javascript-method-closure.html The Idea I had an idea to make a personalized news feed reader. Basically, I'd register a bunch of feeds with the application, and rate a few stories as either "good" or "bad". The application would then use my ratings and the article text to generate a statistical model, apply that ... http://www.chrisspen.com/blog/how-to-extract-a-webpages-main-article-content.html