Apply key transforms to keys referenced in values

2026-01-25 07:16:49 +00:00 · 2016-03-31 14:24:31 -06:00
parent d30aa4c44f
commit 3498647d1a
30 changed files with 579 additions and 223 deletions
--- a/test/action_controller/json_api/key_transform_test.rb
+++ b/test/action_controller/json_api/key_transform_test.rb
@@ -10,7 +10,7 @@ module ActionController
            type 'posts'
            attributes :title, :body, :publish_at
            belongs_to :author
-            has_many :comments
+            has_many :top_comments

            link(:post_authors) { 'https://example.com/post_authors' }

@@ -28,9 +28,9 @@ module ActionController
            attributes :first_name, :last_name
          end

-          Comment = Class.new(::Model)
-          class CommentSerializer < ActiveModel::Serializer
-            type 'comments'
+          TopComment = Class.new(::Model)
+          class TopCommentSerializer < ActiveModel::Serializer
+            type 'top_comments'
            attributes :body
            belongs_to :author
          end
@@ -38,28 +38,28 @@ module ActionController
          def setup_post
            ActionController::Base.cache_store.clear
            @author = Author.new(id: 1, first_name: 'Bob', last_name: 'Jones')
-            @comment1 = Comment.new(id: 7, body: 'cool', author: @author)
-            @comment2 = Comment.new(id: 12, body: 'awesome', author: @author)
+            @comment1 = TopComment.new(id: 7, body: 'cool', author: @author)
+            @comment2 = TopComment.new(id: 12, body: 'awesome', author: @author)
            @post = Post.new(id: 1337, title: 'Title 1', body: 'Body 1',
-                             author: @author, comments: [@comment1, @comment2],
+                             author: @author, top_comments: [@comment1, @comment2],
                             publish_at: '2020-03-16T03:55:25.291Z')
            @comment1.post = @post
            @comment2.post = @post
          end

-          def render_resource_with_key_transform
+          def render_resource_with_transform
            setup_post
            render json: @post, serializer: PostSerializer, adapter: :json_api,
                   key_transform: :camel
          end

-          def render_resource_with_key_transform_nil
+          def render_resource_with_transform_nil
            setup_post
            render json: @post, serializer: PostSerializer, adapter: :json_api,
                   key_transform: nil
          end

-          def render_resource_with_key_transform_with_global_config
+          def render_resource_with_transform_with_global_config
            setup_post
            old_transform = ActiveModelSerializers.config.key_transform
            ActiveModelSerializers.config.key_transform = :camel_lower
@@ -70,13 +70,13 @@ module ActionController

        tests KeyTransformTestController

-        def test_render_resource_with_key_transform
-          get :render_resource_with_key_transform
+        def test_render_resource_with_transform
+          get :render_resource_with_transform
          response = JSON.parse(@response.body)
          expected = {
            'Data' => {
              'Id' => '1337',
-              'Type' => 'posts',
+              'Type' => 'Posts',
              'Attributes' => {
                'Title' => 'Title 1',
                'Body' => 'Body 1',
@@ -86,13 +86,13 @@ module ActionController
                'Author' => {
                  'Data' => {
                    'Id' => '1',
-                    'Type' => 'authors'
+                    'Type' => 'Authors'
                  }
                },
-                'Comments' => {
+                'TopComments' => {
                  'Data' => [
-                    { 'Id' => '7', 'Type' => 'comments' },
-                    { 'Id' => '12', 'Type' => 'comments' }
+                    { 'Id' => '7', 'Type' => 'TopComments' },
+                    { 'Id' => '12', 'Type' => 'TopComments' }
                  ]
                }
              },
@@ -105,8 +105,8 @@ module ActionController
          assert_equal expected, response
        end

-        def test_render_resource_with_key_transform_nil
-          get :render_resource_with_key_transform_nil
+        def test_render_resource_with_transform_nil
+          get :render_resource_with_transform_nil
          response = JSON.parse(@response.body)
          expected = {
            'data' => {
@@ -124,10 +124,10 @@ module ActionController
                    'type' => 'authors'
                  }
                },
-                'comments' => {
+                'top-comments' => {
                  'data' => [
-                    { 'id' => '7', 'type' => 'comments' },
-                    { 'id' => '12', 'type' => 'comments' }
+                    { 'id' => '7', 'type' => 'top-comments' },
+                    { 'id' => '12', 'type' => 'top-comments' }
                  ]
                }
              },
@@ -140,8 +140,8 @@ module ActionController
          assert_equal expected, response
        end

-        def test_render_resource_with_key_transform_with_global_config
-          get :render_resource_with_key_transform_with_global_config
+        def test_render_resource_with_transform_with_global_config
+          get :render_resource_with_transform_with_global_config
          response = JSON.parse(@response.body)
          expected =  {
            'data' => {
@@ -159,10 +159,10 @@ module ActionController
                    'type' => 'authors'
                  }
                },
-                'comments' => {
+                'topComments' => {
                  'data' => [
-                    { 'id' => '7', 'type' => 'comments' },
-                    { 'id' => '12', 'type' => 'comments' }
+                    { 'id' => '7', 'type' => 'topComments' },
+                    { 'id' => '12', 'type' => 'topComments' }
                  ]
                }
              },
--- a/test/active_model_serializers/key_transform_test.rb
+++ b/test/active_model_serializers/key_transform_test.rb
@@ -0,0 +1,263 @@
+require 'test_helper'
+
+class ActiveModelSerializers::KeyTransformTest < ActiveSupport::TestCase
+  def test_camel
+    obj = Object.new
+    scenarios = [
+      {
+        value: { :"some-key" => 'value' },
+        expected: { :SomeKey => 'value' }
+      },
+      {
+        value: { :someKey => 'value' },
+        expected: { :SomeKey => 'value' }
+      },
+      {
+        value: { :some_key => 'value' },
+        expected: { :SomeKey => 'value' }
+      },
+      {
+        value: { 'some-key' => 'value' },
+        expected: { 'SomeKey' => 'value' }
+      },
+      {
+        value: { 'someKey' => 'value' },
+        expected: { 'SomeKey' => 'value' }
+      },
+      {
+        value: { 'some_key' => 'value' },
+        expected: { 'SomeKey' => 'value' }
+      },
+      {
+        value: :"some-value",
+        expected: :SomeValue
+      },
+      {
+        value: :some_value,
+        expected: :SomeValue
+      },
+      {
+        value: :someValue,
+        expected: :SomeValue
+      },
+      {
+        value: 'some-value',
+        expected: 'SomeValue'
+      },
+      {
+        value: 'someValue',
+        expected: 'SomeValue'
+      },
+      {
+        value: 'some_value',
+        expected: 'SomeValue'
+      },
+      {
+        value: obj,
+        expected: obj
+      },
+      {
+        value: nil,
+        expected: nil
+      }
+    ]
+    scenarios.each do |s|
+      result = ActiveModelSerializers::KeyTransform.camel(s[:value])
+      assert_equal s[:expected], result
+    end
+  end
+
+  def test_camel_lower
+    obj = Object.new
+    scenarios = [
+      {
+        value: { :"some-key" => 'value' },
+        expected: { :someKey => 'value' }
+      },
+      {
+        value: { :SomeKey => 'value' },
+        expected: { :someKey => 'value' }
+      },
+      {
+        value: { :some_key => 'value' },
+        expected: { :someKey => 'value' }
+      },
+      {
+        value: { 'some-key' => 'value' },
+        expected: { 'someKey' => 'value' }
+      },
+      {
+        value: { 'SomeKey' => 'value' },
+        expected: { 'someKey' => 'value' }
+      },
+      {
+        value: { 'some_key' => 'value' },
+        expected: { 'someKey' => 'value' }
+      },
+      {
+        value: :"some-value",
+        expected: :someValue
+      },
+      {
+        value: :SomeValue,
+        expected: :someValue
+      },
+      {
+        value: :some_value,
+        expected: :someValue
+      },
+      {
+        value: 'some-value',
+        expected: 'someValue'
+      },
+      {
+        value: 'SomeValue',
+        expected: 'someValue'
+      },
+      {
+        value: 'some_value',
+        expected: 'someValue'
+      },
+      {
+        value: obj,
+        expected: obj
+      },
+      {
+        value: nil,
+        expected: nil
+      }
+    ]
+    scenarios.each do |s|
+      result = ActiveModelSerializers::KeyTransform.camel_lower(s[:value])
+      assert_equal s[:expected], result
+    end
+  end
+
+  def test_dash
+    obj = Object.new
+    scenarios = [
+      {
+        value: { :some_key => 'value' },
+        expected: { :"some-key" => 'value' }
+      },
+      {
+        value: { 'some_key' => 'value' },
+        expected: { 'some-key' => 'value' }
+      },
+      {
+        value: { :SomeKey => 'value' },
+        expected: { :"some-key" => 'value' }
+      },
+      {
+        value: { 'SomeKey' => 'value' },
+        expected: { 'some-key' => 'value' }
+      },
+      {
+        value: { :someKey => 'value' },
+        expected: { :"some-key" => 'value' }
+      },
+      {
+        value: { 'someKey' => 'value' },
+        expected: { 'some-key' => 'value' }
+      },
+      {
+        value: :some_value,
+        expected: :"some-value"
+      },
+      {
+        value: :SomeValue,
+        expected: :"some-value"
+      },
+      {
+        value: 'SomeValue',
+        expected: 'some-value'
+      },
+      {
+        value: :someValue,
+        expected: :"some-value"
+      },
+      {
+        value: 'someValue',
+        expected: 'some-value'
+      },
+      {
+        value: obj,
+        expected: obj
+      },
+      {
+        value: nil,
+        expected: nil
+      }
+    ]
+    scenarios.each do |s|
+      result = ActiveModelSerializers::KeyTransform.dash(s[:value])
+      assert_equal s[:expected], result
+    end
+  end
+
+  def test_underscore
+    obj = Object.new
+    scenarios = [
+      {
+        value: { :"some-key" => 'value' },
+        expected: { :some_key => 'value' }
+      },
+      {
+        value: { 'some-key' => 'value' },
+        expected: { 'some_key' => 'value' }
+      },
+      {
+        value: { :SomeKey => 'value' },
+        expected: { :some_key => 'value' }
+      },
+      {
+        value: { 'SomeKey' => 'value' },
+        expected: { 'some_key' => 'value' }
+      },
+      {
+        value: { :someKey => 'value' },
+        expected: { :some_key => 'value' }
+      },
+      {
+        value: { 'someKey' => 'value' },
+        expected: { 'some_key' => 'value' }
+      },
+      {
+        value: :"some-value",
+        expected: :some_value
+      },
+      {
+        value: :SomeValue,
+        expected: :some_value
+      },
+      {
+        value: :someValue,
+        expected: :some_value
+      },
+      {
+        value: 'some-value',
+        expected: 'some_value'
+      },
+      {
+        value: 'SomeValue',
+        expected: 'some_value'
+      },
+      {
+        value: 'someValue',
+        expected: 'some_value'
+      },
+      {
+        value: obj,
+        expected: obj
+      },
+      {
+        value: nil,
+        expected: nil
+      }
+    ]
+    scenarios.each do |s|
+      result = ActiveModelSerializers::KeyTransform.underscore(s[:value])
+      assert_equal s[:expected], result
+    end
+  end
+end
--- a/test/adapter/json/transform_test.rb
+++ b/test/adapter/json/transform_test.rb
@@ -8,8 +8,8 @@ module ActiveModelSerializers
          context = Minitest::Mock.new
          context.expect(:request_url, URI)
          context.expect(:query_parameters, {})
-          context.expect(:key_transform, key_transform)
          @options = {}
+          @options[:key_transform] = key_transform if key_transform
          @options[:serialization_context] = context
        end

@@ -25,14 +25,14 @@ module ActiveModelSerializers
          @adapter = ActiveModelSerializers::Adapter::Json.new(serializer)
        end

-        def test_key_transform_default
+        def test_transform_default
          mock_request
          assert_equal({
            blog: { id: 1, special_attribute: 'neat', articles: nil }
          }, @adapter.serializable_hash(@options))
        end

-        def test_key_transform_global_config
+        def test_transform_global_config
          mock_request
          result = with_config(key_transform: :camel_lower) do
            @adapter.serializable_hash(@options)
@@ -42,7 +42,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_key_transform_serialization_ctx_overrides_global_config
+        def test_transform_serialization_ctx_overrides_global_config
          mock_request(:camel)
          result = with_config(key_transform: :camel_lower) do
            @adapter.serializable_hash(@options)
@@ -52,7 +52,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_key_transform_undefined
+        def test_transform_undefined
          mock_request(:blam)
          result = nil
          assert_raises NoMethodError do
@@ -60,28 +60,28 @@ module ActiveModelSerializers
          end
        end

-        def test_key_transform_dashed
-          mock_request(:dashed)
+        def test_transform_dash
+          mock_request(:dash)
          assert_equal({
            blog: { id: 1, :"special-attribute" => 'neat', articles: nil }
          }, @adapter.serializable_hash(@options))
        end

-        def test_key_transform_unaltered
+        def test_transform_unaltered
          mock_request(:unaltered)
          assert_equal({
            blog: { id: 1, special_attribute: 'neat', articles: nil }
          }, @adapter.serializable_hash(@options))
        end

-        def test_key_transform_camel
+        def test_transform_camel
          mock_request(:camel)
          assert_equal({
            Blog: { Id: 1, SpecialAttribute: 'neat', Articles: nil }
          }, @adapter.serializable_hash(@options))
        end

-        def test_key_transform_camel_lower
+        def test_transform_camel_lower
          mock_request(:camel_lower)
          assert_equal({
            blog: { id: 1, specialAttribute: 'neat', articles: nil }
--- a/test/adapter/json_api/has_many_test.rb
+++ b/test/adapter/json_api/has_many_test.rb
@@ -129,7 +129,7 @@ module ActiveModelSerializers
          assert_equal({
            data: {
              id: '1',
-              type: 'virtual_values',
+              type: 'virtual-values',
              relationships: {
                maker: { data: { id: 1 } },
                reviews: { data: [{ id: 1 }, { id: 2 }] }
--- a/test/adapter/json_api/has_one_test.rb
+++ b/test/adapter/json_api/has_one_test.rb
@@ -63,7 +63,7 @@ module ActiveModelSerializers
          expected = {
            data: {
              id: '1',
-              type: 'virtual_values',
+              type: 'virtual-values',
              relationships: {
                maker: { data: { id: 1 } },
                reviews: { data: [{ id: 1 }, { id: 2 }] }
--- a/test/adapter/json_api/linked_test.rb
+++ b/test/adapter/json_api/linked_test.rb
@@ -216,7 +216,7 @@ module ActiveModelSerializers
          expected = {
            related: {
              data: [{
-                type: 'spam_unrelated_links',
+                type: 'spam-unrelated-links',
                id: '456'
              }]
            }
@@ -366,12 +366,12 @@ module ActiveModelSerializers
            adapter: :json_api,
            include: '*').serializable_hash
          expected = [
-            type: 'nested_posts', id: '2',
+            type: 'nested-posts', id: '2',
            relationships: {
-              nested_posts: {
+              :"nested-posts" => {
                data: [
-                  { type: 'nested_posts', id: '1' },
-                  { type: 'nested_posts', id: '2' }
+                  { type: 'nested-posts', id: '1' },
+                  { type: 'nested-posts', id: '2' }
                ]
              }
            }
--- a/test/adapter/json_api/links_test.rb
+++ b/test/adapter/json_api/links_test.rb
@@ -80,10 +80,10 @@ module ActiveModelSerializers
              }
            },
            author: 'http://example.com/link_authors/1337',
-            link_authors: 'http://example.com/link_authors',
+            :"link-authors" => 'http://example.com/link_authors',
            resource: 'http://example.com/resource',
            posts: 'http://example.com/link_authors/1337/posts',
-            yet_another: 'http://example.com/resource/1337'
+            :"yet-another" => 'http://example.com/resource/1337'
          }
          assert_equal(expected, hash[:data][:links])
        end
--- a/test/adapter/json_api/pagination_links_test.rb
+++ b/test/adapter/json_api/pagination_links_test.rb
@@ -25,7 +25,6 @@ module ActiveModelSerializers
          context = Minitest::Mock.new
          context.expect(:request_url, original_url)
          context.expect(:query_parameters, query_parameters)
-          context.expect(:key_transform, nil)
          @options = {}
          @options[:serialization_context] = context
        end
--- a/test/adapter/json_api/relationship_test.rb
+++ b/test/adapter/json_api/relationship_test.rb
@@ -151,11 +151,8 @@ module ActiveModelSerializers
        private

        def test_relationship(expected, params = {})
-          options = params.fetch(:options, {})
-          links = params.fetch(:links, {})
-          meta = params[:meta]
          parent_serializer = AuthorSerializer.new(@author)
-          relationship = Relationship.new(parent_serializer, @serializer, options, links, meta)
+          relationship = Relationship.new(parent_serializer, @serializer, nil, params)
          assert_equal(expected, relationship.as_json)
        end
      end
--- a/test/adapter/json_api/resource_identifier_test.rb
+++ b/test/adapter/json_api/resource_identifier_test.rb
@@ -22,7 +22,7 @@ module ActiveModelSerializers
        end

        def test_defined_type
-          test_type(WithDefinedTypeSerializer, 'with_defined_type')
+          test_type(WithDefinedTypeSerializer, 'with-defined-type')
        end

        def test_singular_type
@@ -58,7 +58,7 @@ module ActiveModelSerializers

        def test_type(serializer_class, expected_type)
          serializer = serializer_class.new(@model)
-          resource_identifier = ResourceIdentifier.new(serializer)
+          resource_identifier = ResourceIdentifier.new(serializer, nil)
          expected = {
            id: @model.id.to_s,
            type: expected_type
@@ -69,7 +69,7 @@ module ActiveModelSerializers

        def test_id(serializer_class, id)
          serializer = serializer_class.new(@model)
-          resource_identifier = ResourceIdentifier.new(serializer)
+          resource_identifier = ResourceIdentifier.new(serializer, nil)
          inflection = ActiveModelSerializers.config.jsonapi_resource_type
          type = @model.class.model_name.send(inflection)
          expected = {
--- a/test/adapter/json_api/resource_meta_test.rb
+++ b/test/adapter/json_api/resource_meta_test.rb
@@ -54,7 +54,7 @@ module ActiveModel
              adapter: :json_api
            ).serializable_hash
            expected = {
-              comments_count: @post.comments.count
+              :"comments-count" => @post.comments.count
            }
            assert_equal(expected, hash[:data][:meta])
          end
@@ -69,8 +69,8 @@ module ActiveModel
            ).serializable_hash
            expected = {
              :data => [
-                { :id => '1337', :type => 'posts', :meta => { :comments_count => 0 } },
-                { :id => '1339', :type => 'posts', :meta => { :comments_count => 1 } }
+                { :id => '1337', :type => 'posts', :meta => { :"comments-count" => 0 } },
+                { :id => '1339', :type => 'posts', :meta => { :"comments-count" => 1 } }
              ]
            }
            assert_equal(expected, hash)
--- a/test/adapter/json_api/transform_test.rb
+++ b/test/adapter/json_api/transform_test.rb
@@ -36,13 +36,13 @@ module ActiveModelSerializers
          belongs_to :author
        end

-        def mock_request(key_transform = nil)
+        def mock_request(transform = nil)
          context = Minitest::Mock.new
          context.expect(:request_url, URI)
          context.expect(:query_parameters, {})
-          context.expect(:key_transform, key_transform)
          context.expect(:url_helpers, Rails.application.routes.url_helpers)
          @options = {}
+          @options[:key_transform] = transform if transform
          @options[:serialization_context] = context
        end

@@ -64,7 +64,7 @@ module ActiveModelSerializers
          @comment2.post = @post
        end

-        def test_success_document_key_transform_default
+        def test_success_document_transform_default
          mock_request
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
@@ -98,7 +98,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_document_key_transform_global_config
+        def test_success_document_transform_global_config
          mock_request
          result = with_config(key_transform: :camel_lower) do
            serializer = PostSerializer.new(@post)
@@ -134,7 +134,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_doc_key_transform_serialization_ctx_overrides_global
+        def test_success_doc_transform_serialization_ctx_overrides_global
          mock_request(:camel)
          result = with_config(key_transform: :camel_lower) do
            serializer = PostSerializer.new(@post)
@@ -144,7 +144,7 @@ module ActiveModelSerializers
          assert_equal({
            Data: {
              Id: '1337',
-              Type: 'posts',
+              Type: 'Posts',
              Attributes: {
                Title: 'Title 1',
                Body: 'Body 1',
@@ -152,12 +152,12 @@ module ActiveModelSerializers
              },
              Relationships: {
                Author: {
-                  Data: { Id: '1', Type: 'authors' }
+                  Data: { Id: '1', Type: 'Authors' }
                },
                Comments: {
                  Data: [
-                    { Id: '7', Type: 'comments' },
-                    { Id: '12', Type: 'comments' }
+                    { Id: '7', Type: 'Comments' },
+                    { Id: '12', Type: 'Comments' }
                ] }
              },
              Links: {
@@ -170,8 +170,8 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_document_key_transform_dashed
-          mock_request(:dashed)
+        def test_success_document_transform_dash
+          mock_request(:dash)
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
          result = adapter.serializable_hash(@options)
@@ -204,7 +204,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_document_key_transform_unaltered
+        def test_success_document_transform_unaltered
          mock_request(:unaltered)
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
@@ -238,7 +238,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_document_key_transform_undefined
+        def test_success_document_transform_undefined
          mock_request(:zoot)
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
@@ -247,7 +247,7 @@ module ActiveModelSerializers
          end
        end

-        def test_success_document_key_transform_camel
+        def test_success_document_transform_camel
          mock_request(:camel)
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
@@ -255,7 +255,7 @@ module ActiveModelSerializers
          assert_equal({
            Data: {
              Id: '1337',
-              Type: 'posts',
+              Type: 'Posts',
              Attributes: {
                Title: 'Title 1',
                Body: 'Body 1',
@@ -263,12 +263,12 @@ module ActiveModelSerializers
              },
              Relationships: {
                Author: {
-                  Data: { Id: '1', Type: 'authors' }
+                  Data: { Id: '1', Type: 'Authors' }
                },
                Comments: {
                  Data: [
-                    { Id: '7', Type: 'comments' },
-                    { Id: '12', Type: 'comments' }
+                    { Id: '7', Type: 'Comments' },
+                    { Id: '12', Type: 'Comments' }
                ] }
              },
              Links: {
@@ -281,7 +281,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_success_document_key_transform_camel_lower
+        def test_success_document_transform_camel_lower
          mock_request(:camel_lower)
          serializer = PostSerializer.new(@post)
          adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
@@ -315,7 +315,7 @@ module ActiveModelSerializers
          }, result)
        end

-        def test_error_document_key_transform_default
+        def test_error_document_transform_default
          mock_request
          resource = ModelWithErrors.new
          resource.errors.add(:published_at, 'must be in the future')
@@ -327,7 +327,7 @@ module ActiveModelSerializers
            { :errors =>
              [
                {
-                  :source => { :pointer => '/data/attributes/published_at' },
+                  :source => { :pointer => '/data/attributes/published-at' },
                  :detail => 'must be in the future' },
                {
                  :source => { :pointer => '/data/attributes/title' },
@@ -338,7 +338,7 @@ module ActiveModelSerializers
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_global_config
+        def test_error_document_transform_global_config
          mock_request
          result = with_config(key_transform: :camel) do
            resource = ModelWithErrors.new
@@ -352,11 +352,11 @@ module ActiveModelSerializers
            { :Errors =>
              [
                {
-                  :Source => { :Pointer => '/data/attributes/published_at' },
+                  :Source => { :Pointer => '/data/attributes/PublishedAt' },
                  :Detail => 'must be in the future'
                },
                {
-                  :Source => { :Pointer => '/data/attributes/title' },
+                  :Source => { :Pointer => '/data/attributes/Title' },
                  :Detail => 'must be longer'
                }
              ]
@@ -364,7 +364,7 @@ module ActiveModelSerializers
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_serialization_ctx_overrides_global
+        def test_error_document_transform_serialization_ctx_overrides_global
          mock_request(:camel)
          result = with_config(key_transform: :camel_lower) do
            resource = ModelWithErrors.new
@@ -378,11 +378,11 @@ module ActiveModelSerializers
            { :Errors =>
              [
                {
-                  :Source => { :Pointer => '/data/attributes/published_at' },
+                  :Source => { :Pointer => '/data/attributes/PublishedAt' },
                  :Detail => 'must be in the future'
                },
                {
-                  :Source => { :Pointer => '/data/attributes/title' },
+                  :Source => { :Pointer => '/data/attributes/Title' },
                  :Detail => 'must be longer'
                }
              ]
@@ -390,8 +390,8 @@ module ActiveModelSerializers
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_dashed
-          mock_request(:dashed)
+        def test_error_document_transform_dash
+          mock_request(:dash)

          resource = ModelWithErrors.new
          resource.errors.add(:published_at, 'must be in the future')
@@ -405,7 +405,7 @@ module ActiveModelSerializers
            { :errors =>
              [
                {
-                  :source => { :pointer => '/data/attributes/published_at' },
+                  :source => { :pointer => '/data/attributes/published-at' },
                  :detail => 'must be in the future'
                },
                {
@@ -417,7 +417,7 @@ module ActiveModelSerializers
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_unaltered
+        def test_error_document_transform_unaltered
          mock_request(:unaltered)

          resource = ModelWithErrors.new
@@ -438,7 +438,7 @@ module ActiveModelSerializers
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_undefined
+        def test_error_document_transform_undefined
          mock_request(:krazy)

          resource = ModelWithErrors.new
@@ -453,7 +453,7 @@ module ActiveModelSerializers
          end
        end

-        def test_error_document_key_transform_camel
+        def test_error_document_transform_camel
          mock_request(:camel)

          resource = ModelWithErrors.new
@@ -467,14 +467,14 @@ module ActiveModelSerializers
          expected_errors_object =
            { :Errors =>
              [
-                { :Source => { :Pointer => '/data/attributes/published_at' }, :Detail => 'must be in the future' },
-                { :Source => { :Pointer => '/data/attributes/title' }, :Detail => 'must be longer' }
+                { :Source => { :Pointer => '/data/attributes/PublishedAt' }, :Detail => 'must be in the future' },
+                { :Source => { :Pointer => '/data/attributes/Title' }, :Detail => 'must be longer' }
              ]
          }
          assert_equal expected_errors_object, result
        end

-        def test_error_document_key_transform_camel_lower
+        def test_error_document_transform_camel_lower
          mock_request(:camel_lower)

          resource = ModelWithErrors.new
@@ -488,7 +488,7 @@ module ActiveModelSerializers
          expected_errors_object =
            { :errors =>
              [
-                { :source => { :pointer => '/data/attributes/published_at' }, :detail => 'must be in the future' },
+                { :source => { :pointer => '/data/attributes/publishedAt' }, :detail => 'must be in the future' },
                { :source => { :pointer => '/data/attributes/title' }, :detail => 'must be longer' }
              ]
          }
--- a/test/benchmark/bm_caching.rb
+++ b/test/benchmark/bm_caching.rb
@@ -70,7 +70,8 @@ class ApiAssertion
          },
          'author' => {
            'id' => 42,
-            'name' => 'Joao Moura.'
+            'first_name' => 'Joao',
+            'last_name' => 'Moura'
          }
        }
    }
--- a/test/benchmark/bm_transform.rb
+++ b/test/benchmark/bm_transform.rb
@@ -0,0 +1,34 @@
+require_relative './benchmarking_support'
+require_relative './app'
+
+time = 10
+disable_gc = true
+ActiveModelSerializers.config.key_transform = :unaltered
+comments = (0..50).map do |i|
+  Comment.new(id: i, body: 'ZOMG A COMMENT')
+end
+author = Author.new(id: 42, first_name: 'Joao', last_name: 'Moura')
+post = Post.new(id: 1337, title: 'New Post', blog: nil, body: 'Body', comments: comments, author: author)
+serializer = PostSerializer.new(post)
+adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer)
+serialization = adapter.as_json
+
+Benchmark.ams('camel', time: time, disable_gc: disable_gc) do
+  ActiveModelSerializers::KeyTransform.camel(serialization)
+end
+
+Benchmark.ams('camel_lower', time: time, disable_gc: disable_gc) do
+  ActiveModelSerializers::KeyTransform.camel_lower(serialization)
+end
+
+Benchmark.ams('dash', time: time, disable_gc: disable_gc) do
+  ActiveModelSerializers::KeyTransform.dash(serialization)
+end
+
+Benchmark.ams('unaltered', time: time, disable_gc: disable_gc) do
+  ActiveModelSerializers::KeyTransform.unaltered(serialization)
+end
+
+Benchmark.ams('underscore', time: time, disable_gc: disable_gc) do
+  ActiveModelSerializers::KeyTransform.underscore(serialization)
+end
--- a/test/benchmark/controllers.rb
+++ b/test/benchmark/controllers.rb
@@ -8,7 +8,7 @@ class PostController < ActionController::Base
      else
        comments = [Comment.new(id: 1, body: 'ZOMG A COMMENT')]
      end
-      author = Author.new(id: 42, name: 'Joao Moura.')
+      author = Author.new(id: 42, first_name: 'Joao', last_name: 'Moura')
      Post.new(id: 1337, title: 'New Post', blog: nil, body: 'Body', comments: comments, author: author)
    end

--- a/test/benchmark/fixtures.rb
+++ b/test/benchmark/fixtures.rb
@@ -1,6 +1,6 @@
 Rails.configuration.serializers = []
 class AuthorSerializer < ActiveModel::Serializer
-  attributes :id, :name
+  attributes :id, :first_name, :last_name

  has_many :posts, embed: :ids
  has_one :bio
@@ -27,6 +27,15 @@ class PostSerializer < ActiveModel::Serializer
  belongs_to :blog, serializer: BlogSerializer
  belongs_to :author, serializer: AuthorSerializer

+  link(:post_authors) { 'https://example.com/post_authors' }
+
+  meta do
+    {
+      rating: 5,
+      favorite_count: 10
+    }
+  end
+
  def blog
    Blog.new(id: 999, name: 'Custom blog')
  end
@@ -34,7 +43,7 @@ end
 Rails.configuration.serializers << PostSerializer

 class CachingAuthorSerializer < AuthorSerializer
-  cache key: 'writer', only: [:name], skip_digest: true
+  cache key: 'writer', only: [:first_name, :last_name], skip_digest: true
 end
 Rails.configuration.serializers << CachingAuthorSerializer

@@ -63,7 +72,8 @@ if ENV['ENABLE_ACTIVE_RECORD'] == 'true'
      t.timestamps null: false
    end
    create_table :authors, force: true do |t|
-      t.string :name
+      t.string :first_name
+      t.string :last_name
      t.timestamps null: false
    end
    create_table :posts, force: true do |t|
@@ -144,7 +154,7 @@ else
  end

  class Author < BenchmarkModel
-    attr_accessor :id, :name, :posts
+    attr_accessor :id, :first_name, :last_name, :posts
  end

  class Post < BenchmarkModel