Rails: Database records with custom route...? - ruby-on-rails

Question

I have a model, target, that holds a number of records that are timestamped. On the corresponding controller, I list the months of those records by doing the following:
In models/target.rb
def month
self.recorded_on.strftime('%B')
end
In controllers/targets_controller.rb
#records = Target.find :all
In views/targets/index.html.haml
%ul
- #records.group_by(&:month).sort.each do |month, data|
%li= link_to month, ''
That all works great for listing the available months for the records that I have. Next, I want to be able to click on the month and get a report of all the records for that month, at the following path generated with year and the month: /targets/2009/04
How would I do this?

Answer 1

Add some named scopes to your Target model to support finding by year and by month number. Something like:
class Target < ActiveRecord::Base
named_scope :by_month,
lambda { |month| { :conditions => ['MONTH(recorded_on) = ?',
month] }}
named_scope :by_year,
lambda { |year| { :conditions => ['YEAR(recorded_on) = ?', year] }}
.
.
.
end
(Note that the conditions here are using MySQL syntax.)
Assuming you're using RESTful routes, set up a named route like the one below in your config/routes.rb file (make sure it's declared before the default route):
map.targets_by_month '/targets/:year/:month', :controller => 'targets',
:requirements => { :year => /\d{4}/, :month => /\d{1,2}/ },
:conditions => { :method => :get }
—You can use this route in your view like this:
<%= link_to 'Show April 2009 Targets', targets_by_month_path('2009', '04') %>
(Note that the leading zero for the month is optional because of the :requirements regular expression in the named route defined above)
Finally, in your TargetsController, set up the index action to use the named_scopes defined earlier:
def index
#records = Target.by_year(params[:year]).by_month(params[:month])
.
.
.
end