Posted on

Passenger and OpenID

I recently updated Passenger 2.0.6 to 2.2.4 and experienced that openID logins were not working anymore. Seems like it tries to log output to some strange log location.

However: If anyone comes across the same problem: Simply add

OpenID::Util.logger = RAILS_DEFAULT_LOGGER

to your environment.rb file and everything will work like a treat again.

Posted on

Rails’ to_xml w/ multiple associations.

This is a pain and took me about an hour to figure out today.

Rails ActiveRecord instances offer a nice function to render xml:

my_model.to_xml()

This method can be fed with a parameter 

:include => []

to have all associations being integrated in the XML tree, just like when calling

my_model = MyModel.find( :include => [association])

But when I tried to use it, it always failed when dealing with nested associations. Until I found out the trick.
This is how it works: Basically you need to build a list of nested hashes.

class Book < ActiveRecord::Base
  has_many :pages
  has_one :owner
end
class Owner < ActiveRecord::Base
  has_many :books
end
class Page < ActiveRecord::Base
  has_many :spots_of_coffees
  belongs_to :book
end
class SpotOfCoffee < ActiveRecord::Base
  belongs_to :page
end

Now, you want to create a nice XML output containing a book, with its owner, pages and all spots of coffee?
Pretty easy:

  @book = Book.first
  includes = {} # let's build a hash; it's easier to read. At least for me...
  includes[:owner] = {} # owner has no association. So, let's take an empty hash as target
  includes[:pages] = { :include => :spots_of_coffee } #load pages and include its spots of coffee
    
  respond_to do |format|
    format.xml  { render :text => @book.to_xml(:include => includes) }
  end
Posted on

Nerd stuff.

Die Agentur Seibert Media hat einen kleinen Programmierer-Wettbewerb laufen:

Wer den schlankesten Code schreibt, der einen Weihnachtsbaum auf dem Bildschirm erzeugt, bekommt einen netten iPod-Schuffle.

Hier mein Beitrag, geschrieben in Ruby:

puts (0..30).map{|x|" "*(30-x)+"XX"*x+"\n"}.join+(" "*29+"||\n")*2

Und die Ausgabe auf der Konsole mit IRB:

                             XX
                            XXXX
                           XXXXXX
                          XXXXXXXX
                         XXXXXXXXXX
                        XXXXXXXXXXXX
                       XXXXXXXXXXXXXX
                      XXXXXXXXXXXXXXXX
                     XXXXXXXXXXXXXXXXXX
                    XXXXXXXXXXXXXXXXXXXX
                   XXXXXXXXXXXXXXXXXXXXXX
                  XXXXXXXXXXXXXXXXXXXXXXXX
                 XXXXXXXXXXXXXXXXXXXXXXXXXX
                XXXXXXXXXXXXXXXXXXXXXXXXXXXX
               XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
             XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
            XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
           XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
          XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
         XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
       XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
     XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
   XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
  XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
                             ||
                             ||