Sean's Obsessions

Load testing a Rails app with JMeter and the authenticity_token

I have been slowly learning how to use JMeter to load test the Small Payroll application. One of the problems has been getting around the CSRF protection that Rails puts in with the authenticity_token parameter. Each form has a hidden form element: <div style="margin:0;padding:0;display:inline"> <input name="authenticity_token" type="hidden" value="16iUP1J2tdSKyvHKgYR/I/og6K7NgPPmTHCZ+idQP4k=" /> </div> The token is also encrypted in the session so that the [...]

Piping with the find command and dealing with spaces

I often use the find command as such: grep foo `find . -name \*.php` which looks for foo in all the PHP files. If the list of files gets too long for the shell, then xargs is the better option: find . -name \*.php | xargs grep foo /dev/null This breaks up the command into manageable chunks. The /dev/null [...]

Command line geolocation

A comment in a Slashdot article lead me to iploc.org, specifically Country names zone which lets you get the country for a given IP address over DNS. I wrapped it in a bash function… throw this at the end of your .bashrc: geo() { dig +short TXT `echo $1 | \ awk -F. '{print $4"."$3"."$2"."$1".cc.iploc.org"}'`;} and you can [...]

A shameless plug for SaaS

In 2008 and 2009, my wife and I hired a nanny a few days a week to take care of our three children. Nothing exciting there. Part of hiring a nanny is that you have to deduct and remit taxes, CPP, and EI. All easy stuff; I’ve taken a payroll course before and the calculators [...]

Top 1 best database management tool – and how to use it

I’m noticing that more and more of the items that pop up in my feed reader are of the “Top N” variety. Some are decent, where the author breaks the topic down into subgroups and then shows one or two tools for each purpose. However some of them are just silly, such as the “top [...]

Moving from github to gemcutter for your rails app’s gems

Much hoopla has been made over Github stopping their gem building service, and for people to use Gemcutter. All the stuff I’ve read has been that gemcutter is much better for publishing Gems, and that it’s easier to find the canonical gem (instead of deciding whether fred-mygem is better than barney-mygem) Fair enough, but what about slobs [...]

Shoulda, nested contexts, and should_change_by

I love some of shoulda’s macros, partially because it forces me to think about my tests and put them in setup blocks, which ends up making things cleaner. So I ran into a case where I do an action and use should_change to make sure that a certain number of rows were added to a table, [...]

svn merge

(this is one of those “so I remember it” posts that might help others) Edit: See below for a more accurate way to merge the trunk back into HEAD I’ve got some code that I’m storing in SVN. In traditional SVN form, I’ve got my repo set up as /trunk /branches So my work is done out of trunk, [...]

Automatic uploading of subid stats for Tracking 202

Tracking202 is a great piece of web tracking software. The thing that annoys me though is that I have to upload subid stats (“Optional Info”) to load in the conversions, unless I use the postback or tracking pixel method (which I don’t always have the option to do, and I’m not a high volume guy [...]

How many Mongrels or FastCGI processes do I need?

I’m sitting in a course on call centre design, and yesterday there was mention of Erlangs, which are a unit of measure of the volume of traffic on a telecommunications network. These Erlangs can be used to calculate how many agents a call centre needs (or, given the number of agents, what service level [...]