I have decided (foolishly?) to grow a mo for movember. Its all for good causes and lets see what happens when I grow a mo…

Mind you, this could all go hideously wrong, particularly I’ve never grown a mo before so I have no idea how to care for a mo. I’m also worried that I may become un-snoggable. Let’s hope not eh?

if you’d like to follow along or even donate I’d be delighted Also you too can register at www.movember.com.

Some days I just despair over apple OS X, its so close to a great operating system but drops the ball time and again with its software. Take a for instance, I had some graphics files that contained wireframes for a web application. I needed to get the RGB values for some colours in said wireframes so I loaded them into preview. Now I simply refuse to pay for Photoshop, I just don’t have the skills to use it and the price tag is enough to dissuade all but the professional graphics market away from Photoshop. So all I have is the Preview decimal RGB values. Bobbins.

So I wrote this small Ruby snippet to get the value converted to hex. Its not clever, its not elegant. However it gets the job done and I wrote it in fifteen minutes, result In order to invoke this simply call the script with

script_name.rb red green blue and watch it spit out the result ready to paste in your CSS:

#!/usr/bin/env ruby
if ARGV.size < 3 then
puts "Wrong number of arguments you need 3 groups of values"
exit
end
output_string = []
for arg in ARGV do
arg_as_number = arg.to_i
output_string << arg_as_number.to_s(16)
end
puts "##{output_string.join}"

So there you go. Although I may recommend the Gimp for some fine graphics editing as it does have a hex value colour picker. One more reason to use Linux if you ask me.

Sometimes you can be seduced by shiny things. I was very seduced by Ruby and Rails (well ActiveRecord really). The premise is so simple, the reailty matches the premise for so long… It’s the development equivalent of finding out Santa Claus doesn’t exist when it becomes hard work. So what happened? Well to begin with no one knew about the Oracle license situation…we wanted to be the quick result people so we started on Postgresql. Coming to our senses we briefly spiked Oracle and found that all was good with migrations and basic data. Excellent, lets pack Oracle in a box untill much further down the line I thought.

Twelve weeks later and the model has grown from about eight objects to twenty. OK, no biggie there. So then I started looking in the code…ah, there’s a lot of erm, SQL in there isn’t there? OK, no biggie Oracle and Postgres aren’t worlds apart as dialects of SQL. Well maybe not but the differences are important. A classic example is how many arguments can you put in a where clause? Answer:
Postgres: As many as you’d like (we passed 10000+ in some queries)
Oracle: 1000
Bobbins! OK, we were being lazy with our use of ActiveRecord, so lets refactor the SQL queries (oh and Oracle? Thanks for that ROWNUM implementation, there is nothing as straightforward as wrapping one select in another). Indexes, on Oracle you’re talking about a thirty character limit, on Postgres there appears to be a limit greater than 256 characters. Migrations now need custom names, harumph!

Then there’s the drivers. In postgres land there’s a pure ruby driver called postgres-pr, which turns out to be pretty nifty, installs everywhere, never chucked an error. Mind you it was slow enough that I wouldn’t use it to run production. In oracle land theres ruby-oci8, which is a wrapper around the OCI libs. The biggest thing here is that the ruby-oci8 lib can deadlock ruby. Now I’m not certain because our environments are a lovely mix of Solaris and Oracle releases and patch levels but I think what happens is that if you use DB backed sessions then the OCI driver tries to create two sessions with the DB and gets in a knot with rails. After two weeks of battling the forces of evil we went to file backed sessions and the problem disappeared. I do see that the ruby-oci project has a version two in the offing, lets hope that sorts out some of the nastiness there. I’ve also noticed that query 1 is mighty expensive, it’s probably a connection setup thing but lordy it’s annoying when you have to stop your dev server every two minutes to hack a model object fix.

This post has lain dormant for a couple of months while I stewed on it and thought about whether or not I should release it, then today happened… We’ve just started a Rails 2 project using Oracle and the first thing we did was install the activerecord oracle adapter (which is now split from core rails), bug #1 was migrations (see update). Migrations for Pete’s sake! So I dusted this post off and if it generates some comments I’m thinking about starting off some sort of Oracle-Rails survivors group.

Update:
The migrations bug can be found on this thread.

Now I’m on the case. The first post was the end of some serious frustration. Once I had nipped through the tutorial for selenium-rc I had the bit between my teeth. So I knew my next step was to drive selenium from Ruby.

To begin with I created a rails project (in my case called did) using:
rails did
After installing the spec::rails plugin (the instructions for which are at this page) I ran the rake task that sets up rspec:
ruby script/generate rspec
Then I created a model and a view using the rspec generators so all the rspec gubbins was properly installed. After which I took the seleium.rb included with the selenium-rc snapshot and popped it into /lib. Then I got the example file and began to hack it for my needs. Once I’d finished I had a nice script that opened my site and then checked it displayed the right text. I started up my selenium server, then my rails server (mongrel if you’re interested) then ran spec:views. So the filesystem layout looks like:

/lib/selenium.rb - the file distributed with selenium-rc that provides ruby commands to drive selenium-rc.
/vendor/selenium-0.9.1 - the location of the selenium-rc server jar.
/vendor/selenium - a symbolic link to selenium-0.9.1


Once I did that I could run the spec you can see at Sample Spec using: spec spec/views/insecure/index_spec.rb
So with a little bit of faffing around I ended up with the spec inside view driving selenium. Whoo-hoo.

Today has been a lesson in frustration. It started with me feeling like crap because I had a cold. Moved through me spilling coffee all over my shirt and finished with a fruitless trawl through google. Essentially I found out that rspec integration with Selenium and Rails is a total black hole.

So my initial goal was to get Selenium working. After about two hours I had nothing… and was just beginning to get a little sweary. For instance I sat with my head in my hands after reading about Selenium for some 15-plus minutes only to find that actually I needed to be looking at Selenium RC. A colossal thanks for nothing there. Then I started trying my hand with the selenium-rc. What happened was I downloaded the release and got everything going with the tutorial you can find at http://www.openqa.org/selenium-rc/tutorial.html. The end of result of which was that I got a firefox message about profile being loaded, sadly no browser or test command success. So then I ask some friends and lo and behold its a well known issue. Simply use a snapshot and you’re gold.

So now I have a working Selenium on Linux and Mac OS X. Expect more posts on rspec and how to get Selenium to work with rspec.

I’ve recently got into Rails at work and had to install a plugin for rails. The docs said I should type:

ruby script/plugin install svn://rubyforge.org/var/svn/rspec/tags/REL_X_Y_Z/rspec_on_rails/vendor/plugins/rspec_on_rails

The firewall at work is configured not to allow svn:// URLs and I needed that for the install. So I had to go home and use dial-up…bobbins. Now I dial up using Windows at home because for some reason Linux PPP connections runs at a speed that takes you back to 1990 (Telstra…what is going on?) .

What made ten minutes of pain into a good hour was the lack of any feedback from the command. For instance the follwoing should install the rspec plugin:
D:\wom-rails\wom\deliverable\ruby\trunk\wom>ruby script\plugin install svn://rub
yforge.org/var/svn/rspec/tags/REL_0_8_2/rspec_on_rails/vendor/plugins/rspec_on_rails

D:\wom-rails\wom\deliverable\ruby\trunk\wom>ruby script\generate rspec
Couldn't find 'rspec' generator
Erm, can we have an error message on install please? Well, it turns out if you use the -x option then the following appears:
D:\wom-rails\wom\deliverable\ruby\trunk\wom>ruby script\plugin install -v svn://rub
yforge.org/var/svn/rspec/tags/REL_0_8_2/rspec_on_rails/vendor/plugins/rspec_on_rails
Then you get:
Cannot install using subversion because `svn' cannot be found in your PATH
Result! I haven’t installed the subversion client. SO lets give it another shot:

C:\rails-apps\test>ruby script\plugin install svn://rubyforge.org/var/svn/rspec/
tags/REL_0_8_2/rspec_on_rails/vendor/plugins/rspec_on_rails
A C:\rails-apps\test\vendor\plugins\rspec_on_rails
A C:\rails-apps\test\vendor\plugins\rspec_on_rails\Rakefile
[loads of lines snipped]
A C:\rails-apps\test\vendor\plugins\rspec_on_rails\spec\spec_helper.rb
A C:\rails-apps\test\vendor\plugins\rspec_on_rails\README
Exported revision 1641.

Something appeared! Now let’s give it a pop:

C:\rails-apps\test>ruby script\generate rspec
create spec
create spec/spec_helper.rb
create spec/spec.opts
create script/rails_spec_server

C:\rails-apps\test>

I hope that spares you some pain.

Recently I went to the mighty LugRadio Live (LRL) event. Ever since last year’s LRL (when I did a lightening talk on DR) I’ve been thinking about concentrating on Linux disaster recovery and really trying to expand the information on getting Linux running again after a disaster. Afer a couple of chats this year I’ve decided to pull my finger out and start committing some of this stuff to web. Expect to see more as the time goes on.

Yup, it’s done (well actually I did it a few weeks ago). I have been unpacking my crap and getting around Melbourne, which has been very pleasant. I just can’t believe how friendly people are out here. For instance, I was coming out of Southern Cross station and needed to cross the road. At the intersection I saw a bump between a van and a taxi. Both drivers were OK (at least OK enough to cusss each other for the smash) so there was no real drama. Then as I crossed the intersection I discussed the rights and wrongs of the matter with a guy in a suit, a woman and a hobo. Where else do you get people this freindly?

Hi,
After various abortive attempts to get something running on grinning-cat I’ve taken the advice of the chaps on WYLUG and gone for Wordpress. I’m now going to try and figure out the following:

• whether a decent theme exists for wordpress – that is different from the perfectly passable initial theme
• how to upload content
• what tweaks I wish to make to the site – cue downtime

So hello and welcome, I hope you find what you came for
Robert.