I have been developing a plugin for ruby on rails that can function as an admin framework for entering and managing data, but also as a higher level abstraction that is useful for many web applications. Yet, I have not put much effort into both getting the word out, as well as explaining to people how it works. In an attempt to improve on both of those, I am excited to be presenting to the Ottawa ruby group (ogre) tomorrow, March 28.

Wanna clone shopify.com? Find out how you too can speed up your web development so fast that you only have to work one week per year! Spend the rest of the year floating in the sea of money generated by your uber app! This session will walk through creating a sample web application using Roar, the all singing, all dancing rails plugin that promises to not only make you rich and famous, but cure world peace too!

With that introduction (either excited exuberance or overreaching hyperbole, I haven’t decided), how can anything possibly go wrong?

• When: Wednesday March 28th at 7pm
• Where: Army Officers Mess – 149 Somerset Street West – near the corner of Elgin and Somerset Street.

And in other Ottawa related tech happenings, BarCampOttawa3 is set to go down this Saturday.

Update: Well, that was an interesting presentation—the feedback was largely positive. However, it seems that I lost a good portion of the audience by going too fast and trying to cover too much. Hopefully I can use the feedback to communicate more effectively.

I think I’ve configured the firewall in a completely different way on every server that I’ve set up (for example configuring iptables manually, using a shell script to bootstrap the iptables script, or using firestarter). Continuing that trend, my latest vps is no different, except this time I am actually pleased with the solution. http://firehol.sourceforge.net/ provides a simple language for building firewalls that it then uses to build the iptables.

Yes, the thought of yet another language had me wary, but it truly seems to be both simple and powerful. Here’s a sample firewall configuration that matches all eth2 interfaces, and allows incoming smtp,http,https and ssh services, and all outgoing traffic.

Firehol’s Firewall DSL

interface eth2+ internet
        server smtp accept
        server http accept
        server https accept
        server ssh accept
        client all accept

Start the firehol script (which installs the iptables rules, and is not a resident program), and you’re good to go.