@@ -1,11 +1,22 @@ -== Fetches == += Fetches Fetches is a simple extension to ActionController that allows you to DRY up your model fetching with a simple, intuitive syntax. Rather than creating helpers or manually finding records each time an action is processed, simply add a call to 'fetches' in your controller and it will take care of the rest. -== Example == +== Installation + +Fetches is available as a gem as well as in traditional plugin format. To install +as a gem, add this to your environment.rb: + + config.gem 'mbleigh-fetches', :source => 'http://gems.github.com', :lib => "fetches" + +To install it as a traditional plugin: + + script/plugin install git://github.com/mbleigh/fetches.git + +== Example class UsersController < ApplicationController fetches :user @@ -26,6 +37,13 @@ It's very simple, and can also be extended to meet more complex demands, such as author # equivalent to User.find_by_login(params[:user_id]) end end + +You may also pass a Proc into the "from" option in order to fetch from +a more complex set of requirements: + + class UsersController < ApplicationController + fetches :user, :from => Proc.new{ |c| c.params[:user_id] || c.params[:id] } + end The helper method generated memoizes (initializes once then doesn't make additional calls to the database) and is available both in the controller and the view. README @@ -5,6 +5,10 @@ module ActionController @@default_fetcher_options = { :using => "find", :from => :id } cattr_accessor :default_fetcher_options + + def self.fetchers + read_inheritable_attribute(:fetchers) || write_inheritable_attribute(:fetchers, {}) + end # Automatically creates a helper method to fetch a memoized record based on # a passed-in parameter. @@ -21,10 +25,16 @@ module ActionController # fetches :article # end # + # # Example with Proc-based 'from' + # class UsersController < ApplicationController + # fetches :user, :from => Proc.new{ |c| c.params[:user_id] || c.params[:id] } + # end + # # Options: # # - +as+: the name of the helper method to generate (default is the model name) - # - +from+: the parameter passed into the finder method (default is +:id+) + # - +from+: the parameter passed into the finder method (default is +:id+). + # May also be passed as a +Proc+ that evaluates against a controller argument. # - +using+: the class method name to use as a finder (default is +"find"+) # # Default options may be specified by setting them in an initializer. Example: @@ -34,15 +44,17 @@ module ActionController method_name = options.delete(:as) || default_fetcher_options[:as] || model_name.to_s finder = options.delete(:using) || default_fetcher_options[:using] from = options.delete(:from) || default_fetcher_options[:from] - klass = self.respond_to?(:class_eval) ? self : self.metaclass + fetchers[method_name.to_sym] = from klass.class_eval <<-EOS, __FILE__, __LINE__ def #{method_name} if defined?(@#{method_name}) @#{method_name} else - @#{method_name} = #{model_name.to_s.classify}.#{finder.to_s}(params[#{from.inspect}]) + fetcher = self.class.fetchers[:#{method_name}] + from = fetcher.is_a?(Proc) ? fetcher.call(self) : params[fetcher] + @#{method_name} = #{model_name.to_s.classify}.#{finder.to_s}(from) end end EOS lib/action_controller/fetches.rb @@ -7,7 +7,7 @@ class FetchTestModel when 2 "two worked" else - raise ActiveRecord::RecordNotFound, "Couldn't find FetchTestModel with ID=#{some_integer.to_i}" + raise "Couldn't find FetchTestModel with ID=#{some_integer.to_i}" end end test/fetcher_test_helper.rb @@ -20,6 +20,6 @@ class FetchesTest < Test::Unit::TestCase controller.params = {:id => 2} assert_equal "two worked", controller.fetch_test_model controller.params = {:id => 3} - assert_throws(ActiveRecord::RecordNotFound) + assert_throws(Exception) end end test/fetches_test.rb 16db8ef3a7ef3a069e66204e2fe4306e14f717cd Michael Bleigh michael@intridea.com http://github.com/mbleigh/fetches/commit/784e946928aea912fd9ff0537c544bbb43eff934 784e946928aea912fd9ff0537c544bbb43eff934 2008-07-28T11:02:52-07:00 2008-07-28T11:02:52-07:00 Allow Proc calls for the :from option. f9ff4d3e2dcc0bef0ebc9322b696af818bec9fa1 Michael Bleigh michael@intridea.com