require 'active_support/json'
require 'active_support/core_ext/class/attribute'
module ActiveModel
# == Active Model JSON Serializer
module Serializers
module JSON
extend ActiveSupport::Concern
include ActiveModel::Serialization
included do
extend ActiveModel::Naming
class_attribute :include_root_in_json
self.include_root_in_json = true
end
# Returns a JSON string representing the model. Some configuration can be
# passed through +options+.
#
# The option <tt>include_root_in_json</tt> controls the top-level behavior
# of +as_json+. If true (the default) +as_json+ will emit a single root
# node named after the object's type. For example:
#
# user = User.find(1)
# user.as_json
# # => { "user": {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true} }
#
# ActiveRecord::Base.include_root_in_json = false
# user.as_json
# # => {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true}
#
# The remainder of the examples in this section assume +include_root_in_json+
# is false.
#
# Without any +options+, the returned JSON string will include all the model's
# attributes. For example:
#
# user = User.find(1)
# user.as_json
# # => {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true}
#
# The <tt>:only</tt> and <tt>:except</tt> options can be used to limit the attributes
# included, and work similar to the +attributes+ method. For example:
#
# user.as_json(:only => [ :id, :name ])
# # => {"id": 1, "name": "Konata Izumi"}
#
# user.as_json(:except => [ :id, :created_at, :age ])
# # => {"name": "Konata Izumi", "awesome": true}
#
# To include the result of some method calls on the model use <tt>:methods</tt>:
#
# user.as_json(:methods => :permalink)
# # => {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true,
# "permalink": "1-konata-izumi"}
#
# To include associations use <tt>:include</tt>:
#
# user.as_json(:include => :posts)
# # => {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true,
# "posts": [{"id": 1, "author_id": 1, "title": "Welcome to the weblog"},
# {"id": 2, author_id: 1, "title": "So I was thinking"}]}
#
# Second level and higher order associations work as well:
#
# user.as_json(:include => { :posts => {
# :include => { :comments => {
# :only => :body } },
# :only => :title } })
# # => {"id": 1, "name": "Konata Izumi", "age": 16,
# "created_at": "2006/08/01", "awesome": true,
# "posts": [{"comments": [{"body": "1st post!"}, {"body": "Second!"}],
# "title": "Welcome to the weblog"},
# {"comments": [{"body": "Don't think too hard"}],
# "title": "So I was thinking"}]}
def as_json(options = nil)
hash = serializable_hash(options)
if include_root_in_json
custom_root = options && options[:root]
hash = { custom_root || self.class.model_name.element => hash }
end
hash
end
def from_json(json)
hash = ActiveSupport::JSON.decode(json)
hash = hash.values.first if include_root_in_json
self.attributes = hash
self
end
end
end
end