require 'active_support/core_ext/hash/except' require 'active_support/core_ext/hash/slice' module ActiveModel # == Active Model Serialization # # Provides a basic serialization to a serializable_hash for your object. # # A minimal implementation could be: # # class Person # # include ActiveModel::Serialization # # attr_accessor :name # # def attributes # {'name' => name} # end # # end # # Which would provide you with: # # person = Person.new # person.serializable_hash # => {"name"=>nil} # person.name = "Bob" # person.serializable_hash # => {"name"=>"Bob"} # # You need to declare some sort of attributes hash which contains the attributes # you want to serialize and their current value. # # Most of the time though, you will want to include the JSON or XML # serializations. Both of these modules automatically include the # ActiveModel::Serialization module, so there is no need to explicitly # include it. # # So a minimal implementation including XML and JSON would be: # # class Person # # include ActiveModel::Serializers::JSON # include ActiveModel::Serializers::Xml # # attr_accessor :name # # def attributes # {'name' => name} # end # # end # # Which would provide you with: # # person = Person.new # person.serializable_hash # => {"name"=>nil} # person.as_json # => {"name"=>nil} # person.to_json # => "{\"name\":null}" # person.to_xml # => "\n {"name"=>"Bob"} # person.as_json # => {"name"=>"Bob"} # person.to_json # => "{\"name\":\"Bob\"}" # person.to_xml # => "\n:only, :except and :methods . module Serialization def serializable_hash(options = nil) options ||= {} attribute_names = attributes.keys.sort if only = options[:only] attribute_names &= Array.wrap(only).map(&:to_s) elsif except = options[:except] attribute_names -= Array.wrap(except).map(&:to_s) end method_names = Array.wrap(options[:methods]).select { |n| respond_to?(n) } Hash[(attribute_names + method_names).map { |n| [n, send(n)] }] end end end