http://www.ahabman.com/blog Thu, 16 Oct 2008 13:01:26 +0000 http://backend.userland.com/rss092 en So I'll never have to write another has_and_belongs_to_many view again, here's a plugin that dynamically makes 2 <ul> lists which you drag and drop both ways to manage the association. http://svn.ahabman.com/public/many_to_many_view/ From the readme: Assumming you have an @project var and you want to associate people with it. <div id="m2m_container"> <%= render :partial => "shared/m2m", ... http://www.ahabman.com/blog/2008/10/ruby-on-rails-has-and-belongs-to-many-view-plugin/ You can't use class variables in rails.  Unless you'd like to develop in production mode (specifically with config.cache_classes = true).  In development mode all classes are reloaded on each request, which clears all class variables. I had the perfect place to use them - while running a mass synchronization, and needing ... http://www.ahabman.com/blog/2008/10/you-cant-use-class-variables-in-rails/ I had a csv like this: object color flavor shape apple red sweet round banana yellow sweet long lemon yellow sour round and I wanted a ruby hash structured like this: { 'apple'=> { 'color'=>'red',  'flavor'=>'sweet', 'shape'=>'round'}, 'banana'=> {  'color'=>'yellow',  'flavor'=>'sweet', 'shape'=>'long'}, 'lemon'=> {   'color'=>'yellow',  'flavor'=>'sour', 'shape'=>'round'} } So I wrote this, which does the job: require "faster_csv" def csv_to_structured_hash arr_of_arrs = FasterCSV.read( 'your.csv' ) stuff = {} header = arr_of_arrs.shift arr_of_arrs.each_with_index do |row, i| thing = { row[0] => ... http://www.ahabman.com/blog/2008/09/ruby-csv-to-structured-hash/ A Django Reinhardt and David Grisman fusion. multitrack mandolins, nylon guitars,  and percusion. http://www.ahabman.com/blog/2008/07/django-tango/ This is a ruby module useful for conversions dealing with length, weight, torque. module Convert   def Convert.number_with_precision(number, precision=2)     "%01.#{precision}f" % number   rescue     number   end   def Convert.mm_to_in(mm, precision=2)     number_with_precision(mm * 0.03937, precision)   end   def Convert.in_to_mm(inches, precision=2)     number_with_precision(inches / 0.03937 , precision)   end   def Convert.feet_to_meters(f, precision=2)     number_with_precision( f * 0.3048, precision)   end   def ... http://www.ahabman.com/blog/2008/07/ruby-conversion-module/ Today I realized that the rails command   redirect_to :back  does not work in Internet Explorer because  redirect_to :back  depends on HTTP_REFERER, which IE does not do.  I was capturing an onclick event with jQuery and was able to sending along the  current URL as a query string, which provided ... http://www.ahabman.com/blog/2008/06/rails-redirect_to-back-in-internet-explorer/ My situation was this - Rails 2.0 app running on slicehost (ubuntu 8.04) in passenger mod_rails The goal was Dynamic PDF generation for a product catalog ( > 100 pages) This event had to be triggered from within the rails request / response cycle, but run outside of it I needed the simplest, fastest, ... http://www.ahabman.com/blog/2008/05/rails-background-process-simple-fast-easy/ http://www.ahabman.com/blog/2008/05/point/ I'm using mod_rails with capistrano and multi-stage (qa, staging, production), and wrote this workaround so that the RAILS_ENV could be set correctly in each stage.  Mod_rails sets RAILS_ENV once in the global server conf file, but I needed it set once for each environment: qa, staging, and production.  I tried ... http://www.ahabman.com/blog/2008/05/mod_rails-set-rails_env-variable-to-qa-staging-or-production/ Here is the jQuery validation plugin fixed up so that it works if you have prototype installed along side jQuery.  I just replaced references to $() with jQuery() in the jQuery.validations.js file. jquery.validate.js with prototype http://www.ahabman.com/blog/2008/05/jquery-validation-with-prototype/