Application error (Rails) (Photo credit: geirarne)

So you’re about to build that next great application and you add rails 3.2.3 to your Gemfile. Then you strike up the server and get an error:

 $ rails server
 /usr/local/lib/ruby/site_ruby/1.8/rubygems.rb:335:in `bin_path': can't find executable rails for rails-3.2.1 (Gem::Exception)
 from /usr/local/bin/rails:19

Resolution: install the railties gem.

$ gem install railties
Successfully installed railties-3.2.3
1 gem installed
Installing ri documentation for railties-3.2.3...
Installing RDoc documentation for railties-3.2.3...

Deciding to install rvm on my development laptop (because I need Ruby 1.9 to work with the latest release of SproutCore), I suddenly find myself receiving the dreaded “version_requirements” error when running a 2.3.x rails application. In all of its glory :

undefined local variable or method `version_requirements' for #<Rails::GemDependency:0x0000010095b248>
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/rails/gem_dependency.rb:119:in `requirement'
/Users/imarichardson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems/source_index.rb:269:in `search'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/rails/vendor_gem_source_index.rb:119:in `search'
/Users/imarichardson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:247:in `activate'
/Users/imarichardson/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems.rb:1276:in `gem'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/rails/gem_dependency.rb:73:in `add_load_paths'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/initializer.rb:301:in `block in add_gem_load_paths'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/initializer.rb:301:in `each'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/initializer.rb:301:in `add_gem_load_paths'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/initializer.rb:132:in `process'
/Users/imarichardson/.rvm/gems/ruby-1.9.2-p180/gems/rails-2.3.5/lib/initializer.rb:113:in `run'

So through the power of Google I come upon this post from Chris Oliver, and just as I’m about to rollback my version of Ruby to a previous one, I check the source and see an even better solution in this discussion thread. Instead of rolling back ruby gems and making everyone suffer, you can add a non-intrusive update to your environment.rb file. Add this block in right before the initialization and all will be well:

if Gem::VERSION >= "1.3.6"
    module Rails
        class GemDependency
            def requirement
                r = super
                (r == Gem::Requirement.default) ? nil : r
            end
        end
    end
end

I had this really amazing plan to actually create a video of the process – first starting with a simple table, then displaying the Maps integration. But, it’s a bit late and I may need to wait a little later.

For the second exercise, the charge was to iterate through a JSON formatted list of students and to output the data into a table or some container of sorts in which you needed to iterate through the object. I figured I’d run it through the Google Maps API and display all the names on a map by City and State using the Lat/Lon values. Here’s my output from the exercise iterating through the array and ultimately loading the map. Yesterday’s post brought to the surface a couple of nuances in dealing with jsFiddle, so in getting things running be sure to take in account a few points of notice:

UPDATE 02/08/2011:

• It looks like this was caused by an issue of the order of the libraries. See the comments below. Looks like it’s just an issue with the loading of the libraries through jsFiddle. Also, for more info checkout the jsFiddle Google Group.
  
  
• Be certain to use the Google JSAPI with the “fake=.js” url parameter (i.e., http://www.google.com/jsapi?fake=.js) to make certain the library loads.
  
  
• Thanks to the developer, Piotr Zalewa, for a quick response.

I’ve come to love jsFiddle. Although I heard about it some time ago I never really got around to doing anything with it until rather recently I joined an online community jQuery course with P2P. (Interesting concept and definitely worth taking a look at.) So in doing so for a recent exercise I decided to use the Google Maps JS API for generating a map with markers for people retrieved form a JSON object. The problem I’m noticing is that the Google APIs don’t seem to work fluidly with jsFiddle.

First the “google” object could not be found when running the page. So, although it’s not ideal, I added it to the html section and the libraries loaded. But now I’m getting an error with the visualization object not being found. I think it’s an issue with jsFiddle at this time, as I’ve actually just copy/pasted the example from the Google Visualization library and it still doesn’t work. I’m putting some feelers out to find out if there really is something going on or if I’m just going crazy in the process.

One last note, too: I highly suggest not using Chrome with jsFiddle, either. On two occasions Chrome just stopped interacting with the UI and I lost all my changes. Especially ugh since there’s not an autosave at this time.

"Crisis" from pdsimao (http://sxc.hu)

What do you do when you come to your site and realize that the last 6 years of data is no longer available and your site has been completely deleted from your web hosting provider? You start over again.

Yes, that’s the story. So thank the web tubes that one can begin again, with new content, new news, and relevant “stuff” altogether. Besides, so much of the old info was outdated and irrelevant (or perhaps that’s what I’m saying to make myself feel better about loosing it all).

Oh well, welcome to the site.