require 'active_support/json' module ActiveRecord #:nodoc: module Serialization class Serializer #:nodoc: attr_reader :options def initialize(record, options = {}) @record, @options = record, options.dup end # To replicate the behavior in ActiveRecord#attributes, # :except takes precedence over :only. If :only is not set # for a N level model but is set for the N+1 level models, # then because :except is set to a default value, the second # level model can have both :except and :only set. So if # :only is set, always delete :except. def serializable_attribute_names attribute_names = @record.attribute_names if options[:only] options.delete(:except) attribute_names = attribute_names & Array(options[:only]).collect { |n| n.to_s } else options[:except] = Array(options[:except]) | Array(@record.class.inheritance_column) attribute_names = attribute_names - options[:except].collect { |n| n.to_s } end attribute_names end def serializable_method_names Array(options[:methods]).inject([]) do |method_attributes, name| method_attributes << name if @record.respond_to?(name.to_s) method_attributes end end def serializable_names serializable_attribute_names + serializable_method_names end # Add associations specified via the :includes option. # Expects a block that takes as arguments: # +association+ - name of the association # +records+ - the association record(s) to be serialized # +opts+ - options for the association records def add_includes(&block) if include_associations = options.delete(:include) base_only_or_except = { :except => options[:except], :only => options[:only] } include_has_options = include_associations.is_a?(Hash) associations = include_has_options ? include_associations.keys : Array(include_associations) for association in associations records = case @record.class.reflect_on_association(association).macro when :has_many, :has_and_belongs_to_many @record.send(association).to_a when :has_one, :belongs_to @record.send(association) end unless records.nil? association_options = include_has_options ? include_associations[association] : base_only_or_except opts = options.merge(association_options) yield(association, records, opts) end end options[:include] = include_associations end end def serializable_record returning(serializable_record = {}) do serializable_names.each { |name| serializable_record[name] = @record.send(name) } add_includes do |association, records, opts| if records.is_a?(Enumerable) serializable_record[association] = records.collect { |r| self.class.new(r, opts).serializable_record } else serializable_record[association] = self.class.new(records, opts).serializable_record end end end end def serialize # overwrite to implement end def to_s(&block) serialize(&block) end end end end require 'active_record/serializers/xml_serializer' require 'active_record/serializers/json_serializer'