Add basic JsonApiObject behavior

Finish rails-api#1147

Author: bf4

CHANGELOG.md

@@ -12,4 +12,4 @@
   * adds FlattenJSON as default adapter [@joaomdmoura]
   * adds support for `pagination links` at top level of JsonApi adapter [@bacarini]
   * adds extended format for `include` option to JsonApi adapter [@beauby]
-  * adds support for top level jsonapi member support [@beauby]
+  * adds support for top level `jsonapi` member [@beauby, @bf4]

docs/general/configuration_options.md

@@ -9,5 +9,9 @@ The following configuration options can be set on `ActiveModel::Serializer.confi
 ## JSON API
 
 - `jsonapi_resource_type`: Whether the `type` attributes of resources should be singular or plural. Possible values: `:singular, :plural`. Default: `:plural`.
-- `jsonapi_toplevel_member`: Whether to include a [top level JSON API member](http://jsonapi.org/format/#document-jsonapi-object) in the response document. Default: `false`.
-- `jsonapi_version`: The latest version of the spec the API conforms to. Used when `jsonapi_toplevel_member` is `true`. Default: `'1.0'`.
+- `jsonapi_toplevel_member`: Whether to include a [top level JSON API member](http://jsonapi.org/format/#document-jsonapi-object)
+   in the response document. Default: `false`.
+- `jsonapi_version`: The latest version of the spec the API conforms to.
+  Used when `jsonapi_toplevel_member` is `true`. Default: `'1.0'`.
+- `jsonapi_toplevel_meta`: Optional metadata. Not included if empty.
+  Used when `jsonapi_toplevel_member` is `true`. Default: `{}`.

lib/active_model/serializable_resource.rb

@@ -1,8 +1,7 @@
 require 'set'
 module ActiveModel
   class SerializableResource
-    ADAPTER_OPTION_KEYS = Set.new([:include, :fields, :adapter,
-                                   :jsonapi_toplevel_meta])
+    ADAPTER_OPTION_KEYS = Set.new([:include, :fields, :adapter])
 
     # Primary interface to composing a resource with a serializer and adapter.
     # @return the serializable_resource, ready for #as_json/#to_json/#serializable_hash.

lib/active_model/serializer/adapter/json_api.rb

@@ -3,48 +3,70 @@ class ActiveModel::Serializer::Adapter::JsonApi < ActiveModel::Serializer::Adapt
         autoload :PaginationLinks
         autoload :FragmentCache
 
-        def initialize(serializer, options = {})
-          super
-          @included = ActiveModel::Serializer::Utils.include_args_to_hash(instance_options[:include])
-          fields = options.delete(:fields)
-          if fields
-            @fieldset = ActiveModel::Serializer::Fieldset.new(fields, serializer.json_key)
-          else
-            @fieldset = options[:fieldset]
+        module ApiObjects
+          # Make JSON API top-level jsonapi member opt-in
+          # ref: http://jsonapi.org/format/#document-top-level
+          ActiveModel::Serializer.config.jsonapi_include_toplevel_member = false
+          ActiveModel::Serializer.config.jsonapi_version = '1.0'
+          ActiveModel::Serializer.config.jsonapi_toplevel_meta = {}
+          module JsonApi
+            extend self
+
+            def include_member?
+              ActiveModel::Serializer.config.jsonapi_include_toplevel_member
+            end
+
+            def add!(document)
+              object = {
+               jsonapi: {
+                 version: ActiveModel::Serializer.config.jsonapi_version,
+                 meta: ActiveModel::Serializer.config.jsonapi_toplevel_meta
+               }
+              }
+              object[:jsonapi].reject! { |_, v| v.blank? }
+              document.merge!(object)
+            end
           end
         end
 
         def serializable_hash(options = nil)
           options ||= {}
-          hash =
-            if serializer.respond_to?(:each)
-              serializable_hash_for_collection(serializer, options)
-            else
-              serializable_hash_for_single_resource(serializer, options)
-            end
-
-          if ActiveModel::Serializer.config.jsonapi_toplevel_member
-            hash[:jsonapi] = {}
-            hash[:jsonapi][:version] = ActiveModel::Serializer.config.jsonapi_version
-            hash[:jsonapi][:meta] = @options[:jsonapi_toplevel_meta] if @options[:jsonapi_toplevel_meta]
+          self.hash = {}
+          if ApiObjects::JsonApi.include_member?
+            ApiObjects::JsonApi.add!(hash)
+          end
+          if serializer.respond_to?(:each)
+            serializable_hash_for_collection(serializer, options)
+          else
+            serializable_hash_for_single_resource(serializer, options)
           end
-
-          hash
         end
 
         def fragment_cache(cached_hash, non_cached_hash)
           root = false if instance_options.include?(:include)
           ActiveModel::Serializer::Adapter::JsonApi::FragmentCache.new.fragment_cache(root, cached_hash, non_cached_hash)
         end
 
+        def fieldset
+          @fieldset ||=
+            begin
+              fields = instance_options.delete(:fields)
+              if fields
+                ActiveModel::Serializer::Fieldset.new(fields, serializer.json_key)
+              else
+                instance_options[:fieldset]
+              end
+            end
+        end
+
         private
 
         ActiveModel.silence_warnings do
-          attr_reader :included, :fieldset
+          attr_accessor :hash
         end
 
         def serializable_hash_for_collection(serializer, options)
-          hash = { data: [] }
+          hash[:data] = []
           serializer.each do |s|
             result = self.class.new(s, instance_options.merge(fieldset: fieldset)).serializable_hash(options)
             hash[:data] << result[:data]
@@ -64,11 +86,13 @@ def serializable_hash_for_collection(serializer, options)
         end
 
         def serializable_hash_for_single_resource(serializer, options)
-          primary_data = primary_data_for(serializer, options)
+          hash[:data] = {}
+          hash[:data].update primary_data_for(serializer, options)
+
           relationships = relationships_for(serializer)
-          included = included_for(serializer)
-          hash = { data: primary_data }
           hash[:data][:relationships] = relationships if relationships.any?
+
+          included = included_for(serializer)
           hash[:included] = included if included.any?
 
           hash
@@ -129,10 +153,13 @@ def relationship_value_for(serializer, options = {})
         end
 
         def relationships_for(serializer)
-          Hash[serializer.associations.map { |association| [association.key, { data: relationship_value_for(association.serializer, association.options) }] }]
+          Hash[serializer.associations.map { |association|
+            [association.key, { data: relationship_value_for(association.serializer, association.options) }]
+          }]
         end
 
         def included_for(serializer)
+          included = ActiveModel::Serializer::Utils.include_args_to_hash(instance_options[:include])
           included.flat_map { |inc|
             association = serializer.associations.find { |assoc| assoc.key == inc.first }
             _included_for(association.serializer, inc.second) if association

lib/active_model/serializer/configuration.rb

@@ -4,12 +4,12 @@ module Configuration
       include ActiveSupport::Configurable
       extend ActiveSupport::Concern
 
+      # Configuration options may also be set in
+      # Serializers and Adapters
       included do |base|
         base.config.array_serializer = ActiveModel::Serializer::ArraySerializer
         base.config.adapter = :flatten_json
         base.config.jsonapi_resource_type = :plural
-        base.config.jsonapi_toplevel_member = false
-        base.config.jsonapi_version = '1.0'
       end
     end
   end

test/adapter/json_api/toplevel_jsonapi_test.rb

@@ -27,58 +27,56 @@ def setup
             @author.posts = []
           end
 
-          def with_config(option, value)
-            old_value = ActiveModel::Serializer.config[option]
-            ActiveModel::Serializer.config[option] = value
-            yield
-          ensure
-            ActiveModel::Serializer.config[option] = old_value
+          def test_toplevel_jsonapi_defaults_to_false
+            assert_equal config.fetch(:jsonapi_include_toplevel_member), false
           end
 
           def test_disable_toplevel_jsonapi
-            with_adapter :json_api do
-              with_config(:jsonapi_toplevel_member, false) do
-                hash = ActiveModel::SerializableResource.new(@post).serializable_hash
-                assert_nil(hash[:jsonapi])
-              end
+            with_config(jsonapi_include_toplevel_member: false) do
+              hash = serialize(@post)
+              assert_nil(hash[:jsonapi])
             end
           end
 
           def test_enable_toplevel_jsonapi
-            with_adapter :json_api do
-              with_config(:jsonapi_toplevel_member, true) do
-                hash = ActiveModel::SerializableResource.new(@post).serializable_hash
-                refute_nil(hash[:jsonapi])
-              end
+            with_config(jsonapi_include_toplevel_member: true) do
+              hash = serialize(@post)
+              refute_nil(hash[:jsonapi])
             end
           end
 
           def test_default_toplevel_jsonapi_version
-            with_adapter :json_api do
-              with_config(:jsonapi_toplevel_member, true) do
-                hash = ActiveModel::SerializableResource.new(@post).serializable_hash
-                assert_equal('1.0', hash[:jsonapi][:version])
-              end
+            with_config(jsonapi_include_toplevel_member: true) do
+              hash = serialize(@post)
+              assert_equal('1.0', hash[:jsonapi][:version])
             end
           end
 
           def test_toplevel_jsonapi_no_meta
-            with_adapter :json_api do
-              with_config(:jsonapi_toplevel_member, true) do
-                hash = ActiveModel::SerializableResource.new(@post).serializable_hash
-                assert_nil(hash[:jsonapi][:meta])
-              end
+            with_config(jsonapi_include_toplevel_member: true) do
+              hash = serialize(@post)
+              assert_nil(hash[:jsonapi][:meta])
             end
           end
 
           def test_toplevel_jsonapi_meta
-            with_adapter :json_api do
-              with_config(:jsonapi_toplevel_member, true) do
-                hash = ActiveModel::SerializableResource.new(@post, jsonapi_toplevel_meta: 'custom').serializable_hash
-                assert_equal('custom', hash[:jsonapi][:meta])
-              end
+            new_config = {
+              jsonapi_include_toplevel_member: true,
+              jsonapi_toplevel_meta: {
+                'copyright': 'Copyright 2015 Example Corp.'
+              }
+            }
+            with_config(new_config) do
+              hash = serialize(@post)
+              assert_equal(new_config[:jsonapi_toplevel_meta], hash.fetch(:jsonapi).fetch(:meta))
             end
           end
+
+          private
+
+          def serialize(resource, options = {})
+            serializable(resource, { adapter: :json_api }.merge!(options)).serializable_hash
+          end
         end
       end
     end

test/support/serialization_testing.rb

@@ -1,4 +1,8 @@
 module SerializationTesting
+  def config
+    ActiveModel::Serializer.config
+  end
+
   private
 
   def generate_cached_serializer(obj)
@@ -18,6 +22,18 @@ def with_adapter(adapter)
     ActiveModel::Serializer.config.adapter = old_adapter
   end
   alias_method :with_configured_adapter, :with_adapter
+
+  def with_config(hash)
+    old_config = config.dup
+    ActiveModel::Serializer.config.update(hash)
+    yield
+  ensure
+    ActiveModel::Serializer.config.replace(old_config)
+  end
+
+  def serializable(resource, options = {})
+    ActiveModel::SerializableResource.new(resource, options)
+  end
 end
 
 class Minitest::Test