require 'activesupport' require 'fastercsv' require 'comma/extractors' class Array def to_comma(style = :default) options = {} if style.is_a? Hash options = style style = options.delete(:style)||:default end FasterCSV.generate(options) do |csv| return "" if empty? csv << first.to_comma_headers(style) # REVISIT: request to optionally include headers each do |object| csv << object.to_comma(style) end end end end class Object class_inheritable_accessor :comma_formats def self.comma(style = :default, &block) (self.comma_formats ||= {})[style] = block end def to_comma(style = :default) raise "No comma format for class #{self.class} defined for style #{style}" unless self.comma_formats and self.comma_formats[style] Comma::DataExtractor.new(self, &self.comma_formats[style]).results end def to_comma_headers(style = :default) raise "No comma format for class #{self.class} defined for style #{style}" unless self.comma_formats and self.comma_formats[style] Comma::HeaderExtractor.new(self, &self.comma_formats[style]).results end end if defined?(ActionController) module RenderAsCSV def self.included(base) base.send :include, InstanceMethods base.alias_method_chain :render, :csv end module InstanceMethods def render_with_csv(options = nil, extra_options = {}, &block) return render_without_csv(options, extra_options, &block) unless options.is_a?(Hash) and options[:csv] data = options.delete(:csv) style = options.delete(:style) || :default send_data Array(data).to_comma(style), options.merge(:type => :csv) end end end ActionController::Base.send :include, RenderAsCSV end