!!! Listings zum Arikel "Edel sei der Stein"
!!! (Ruby-on-Rails-Tutorial III) von Denny Carl
!!! in iX 8/2008, S. 140

!!! Das gesamte Archiv findet sich in diesem Verzeichnis 
!!! als trainspotr3.zip

!!! Listing 1: Session-Handling

def current_user
  session[:current_user]
end
  
protected
def authenticate
  authenticate_or_request_with_http_basic do |login, password|
    session[:current_user] = User.authenticate(login, password)
  end
end  

!!! Listing 2: Rating hinzufügen

class AddRatingToTrainspot < ActiveRecord::Migration
  def self.up
    ActiveRecord::Base.create_ratings_table
    Trainspot.add_ratings_columns
  end

  def self.down
    Trainspot.remove_ratings_columns
    ActiveRecord::Base.drop_ratings_table
  end
end

!!! Listing 3: Rating anzeigen

def show_rating(trainspot)
  if trainspot.rating_count > 0
    return trainspot.rating_average.to_s + " / 5 Punkten"
  else
    return "Keine Bewertung vorhanden"
  end
end

!!! Listing 4: Bewertung abgeben

<% if current_user %>
  <% unless @trainspot.rated_by?(current_user) %>
    <div id="rating_input">Ihre Bewertung:
    <% 5.times do |i| %>
      <%= link_to_remote (i+1).to_s, :url => rate_trainspot_url(@trainspot, :rating => i+1) %>      
    <% end %>
    </div>
  <% end %>
<% end %>

!!! Listing 5: POST-Request

map.resources :trainspots, :member => {:rate => :post} do |trainspot|
  trainspot.resources :photos
end

!!! Listing 6: <I>render<I> mit <I>update<I>-Parameter

render :update do |page|
  page.replace_html 'rating', show_rating(@trainspot)
  page.replace_html 'rating_input', 'Vielen Dank für Ihre Bewertung'
end 


!!! Listing 7: Trainspot-Array mit Instanzen

<ul>
  <% trainspots.each do |trainspot| %>
  <li>  
    <% if trainspot.first_photo %>
      <%= link_to image_tag(trainspot.first_photo.public_filename(:thumb)), trainspot, :title => trainspot.train %> 
    <% else %>
      <%= link_to trainspot.train, trainspot %>
    <% end %>
  </li>
  <% end %>
</ul>

!!! Listing 8: Zusätzliche Trainspot-Klassenmethoden

def self.find_newest
  Trainspot.find(:all, :limit => 5, :order => 'created_at DESC')
end

def self.find_best
  Trainspot.find(:all, :limit => 5, :order => 'rating_avg DESC') 
end

def self.find_random
  Trainspot.find(:all, :limit => 5, :order => 'RAND()')
end

!!! Listing 9: Dreimal Zugsichtungen

<h3>Die neuesten Zugsichtungen</h3>
<%= render :partial => 'shared/trainspot_list', :locals => {:trainspots => Trainspot.find_newest} %> 

<h3>Die besten Zugsichtungen</h3>
<%= render :partial => 'shared/trainspot_list', :locals => {:trainspots => Trainspot.find_best} %> 

<h3>Zufällig ausgewählte Zugsichtungen</h3>
<%= render :partial => 'shared/trainspot_list', :locals => {:trainspots => Trainspot.find_random} %> 

!!! Listing 10: YAML-Daten

one:
  id: 1
  train: BR 201
  location: Berlin Westhafen
  user_id: 1

two:
  id: 2
  train: BR 201
  location: Berlin Westhafen
  user_id: 1
  lat: 52.536821 
  lng: 13.343732

!!! Listing 11:

def test_trainspots_without_lng_and_lat
  t = Trainspot.find 1
  assert_equal false, t.valid?
end

def test_trainspots_with_lng_and_lat
  t = Trainspot.find 2
  assert_equal true, t.valid?
end