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Diffstat (limited to 'activemodel/lib/active_model/serializers/json.rb')
| -rw-r--r-- | activemodel/lib/active_model/serializers/json.rb | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/serializers/json.rb b/activemodel/lib/active_model/serializers/json.rb new file mode 100644 index 0000000000..c58e73f6a7 --- /dev/null +++ b/activemodel/lib/active_model/serializers/json.rb @@ -0,0 +1,145 @@ +require 'active_support/json' + +module ActiveModel + module Serializers + # == Active \Model \JSON \Serializer + module JSON + extend ActiveSupport::Concern + include ActiveModel::Serialization + + included do + extend ActiveModel::Naming + + class_attribute :include_root_in_json + self.include_root_in_json = false + end + + # Returns a hash 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+, +as_json+ will emit a single root node named + # after the object's type. The default value for <tt>include_root_in_json</tt> + # option is +false+. + # + # user = User.find(1) + # user.as_json + # # => { "id" => 1, "name" => "Konata Izumi", "age" => 16, + # # "created_at" => "2006/08/01", "awesome" => true} + # + # ActiveRecord::Base.include_root_in_json = true + # + # user.as_json + # # => { "user" => { "id" => 1, "name" => "Konata Izumi", "age" => 16, + # # "created_at" => "2006/08/01", "awesome" => true } } + # + # This behavior can also be achieved by setting the <tt>:root</tt> option + # to +true+ as in: + # + # user = User.find(1) + # user.as_json(root: true) + # # => { "user" => { "id" => 1, "name" => "Konata Izumi", "age" => 16, + # # "created_at" => "2006/08/01", "awesome" => true } } + # + # Without any +options+, the returned Hash will include all the model's + # attributes. + # + # 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. + # + # 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) + root = if options && options.key?(:root) + options[:root] + else + include_root_in_json + end + + if root + root = self.class.model_name.element if root == true + { root => serializable_hash(options) } + else + serializable_hash(options) + end + end + + # Sets the model +attributes+ from a JSON string. Returns +self+. + # + # class Person + # include ActiveModel::Serializers::JSON + # + # attr_accessor :name, :age, :awesome + # + # def attributes=(hash) + # hash.each do |key, value| + # send("#{key}=", value) + # end + # end + # + # def attributes + # instance_values + # end + # end + # + # json = { name: 'bob', age: 22, awesome:true }.to_json + # person = Person.new + # person.from_json(json) # => #<Person:0x007fec5e7a0088 @age=22, @awesome=true, @name="bob"> + # person.name # => "bob" + # person.age # => 22 + # person.awesome # => true + # + # The default value for +include_root+ is +false+. You can change it to + # +true+ if the given JSON string includes a single root node. + # + # json = { person: { name: 'bob', age: 22, awesome:true } }.to_json + # person = Person.new + # person.from_json(json) # => #<Person:0x007fec5e7a0088 @age=22, @awesome=true, @name="bob"> + # person.name # => "bob" + # person.age # => 22 + # person.awesome # => true + def from_json(json, include_root=include_root_in_json) + hash = ActiveSupport::JSON.decode(json) + hash = hash.values.first if include_root + self.attributes = hash + self + end + end + end +end |