feat: Support Active Model Serializer

Gemfile.lock

@@ -22,6 +22,11 @@ GEM
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    active_model_serializers (0.10.14)
+      actionpack (>= 4.1)
+      activemodel (>= 4.1)
+      case_transform (>= 0.2)
+      jsonapi-renderer (>= 0.1.1.beta1, < 0.3)
     activemodel (7.0.4.3)
       activesupport (= 7.0.4.3)
     activerecord (7.0.4.3)
@@ -36,6 +41,8 @@ GEM
     awesome_print (1.9.2)
     builder (3.2.4)
     byebug (11.1.3)
+    case_transform (0.2)
+      activesupport
     coderay (1.1.3)
     concurrent-ruby (1.2.2)
     crass (1.0.6)
@@ -56,6 +63,7 @@ GEM
     js_from_routes (2.1.0)
       railties (>= 5.1, < 8)
     json (2.6.3)
+    jsonapi-renderer (0.2.2)
     language_server-protocol (3.17.0.3)
     listen (3.8.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
@@ -172,6 +180,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  active_model_serializers (~> 0.10.0)
   activerecord
   bundler (~> 2)
   debug

playground/vanilla/Gemfile

@@ -15,6 +15,9 @@ gem "js_from_routes", "~> 2.0.6"
 # A more efficient version of ActiveModelSerializers (https://github.com/ElMassimo/oj_serializers)
 gem "oj_serializers"
 
+# ActiveModel::Serializer implementation and Rails hooks
+gem "active_model_serializers", "~> 0.10.0"
+
 # Generate TypeScript interfaces from Ruby serializers.
 gem "types_from_serializers", path: "../.."
 

playground/vanilla/Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: ../..
   specs:
-    types_from_serializers (2.0.2)
+    types_from_serializers (2.1.0)
       listen (~> 3.2)
       oj_serializers (~> 2.0, >= 2.0.2)
       railties (>= 5.1)
@@ -45,6 +45,11 @@ GEM
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    active_model_serializers (0.10.14)
+      actionpack (>= 4.1)
+      activemodel (>= 4.1)
+      case_transform (>= 0.2)
+      jsonapi-renderer (>= 0.1.1.beta1, < 0.3)
     activejob (6.0.6.1)
       activesupport (= 6.0.6.1)
       globalid (>= 0.3.6)
@@ -65,6 +70,8 @@ GEM
       tzinfo (~> 1.1)
       zeitwerk (~> 2.2, >= 2.2.2)
     builder (3.2.4)
+    case_transform (0.2)
+      activesupport
     concurrent-ruby (1.2.2)
     crass (1.0.6)
     date (3.3.3)
@@ -86,6 +93,7 @@ GEM
       reline (>= 0.3.0)
     js_from_routes (2.0.6)
       railties (>= 5.1, < 8)
+    jsonapi-renderer (0.2.2)
     listen (3.8.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
@@ -209,6 +217,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  active_model_serializers (~> 0.10.0)
   debug
   inertia_rails (>= 1.2.2)
   js_from_routes (~> 2.0.6)

playground/vanilla/app/serializers/ams/base_serializer.rb

@@ -0,0 +1,3 @@
+class Ams::BaseSerializer < ActiveModel::Serializer
+  include TypesFromSerializers::Ams
+end

playground/vanilla/app/serializers/ams/composer_serializer.rb

@@ -0,0 +1,5 @@
+class Ams::ComposerSerializer < Ams::BaseSerializer
+  object_as :composer
+
+  attributes :id, :first_name, :last_name
+end

playground/vanilla/app/serializers/ams/song_serializer.rb

@@ -0,0 +1,10 @@
+class Ams::SongSerializer < Ams::BaseSerializer
+  object_as :song
+
+  attributes(
+    :id,
+    :title,
+  )
+
+  has_one :composer, serializer: Ams::ComposerSerializer
+end

spec/spec_helper.rb

@@ -8,6 +8,7 @@
 require "rails"
 require "oj_serializers"
 require "types_from_serializers"
+require "active_model_serializers"
 require "rspec/given"
 
 begin

spec/types_from_serializers/__snapshots__/interfaces_index.snap

@@ -1,4 +1,4 @@
-// TypesFromSerializers CacheKey 6e82f9b05515cf2d2fd0ea698478f2de
+// TypesFromSerializers CacheKey fda33f0b08d157334e88f37f595d5aa1
 //
 // DO NOT MODIFY: This file was automatically generated by TypesFromSerializers.
 export type { default as Composer } from './Composer'

spec/types_from_serializers/ams/__snapshots__/interfaces_Ams__ComposerSerializer.snap

@@ -0,0 +1,9 @@
+// TypesFromSerializers CacheKey 4cc2e79f18cd24f4999baf4b30ea3fef
+//
+// DO NOT MODIFY: This file was automatically generated by TypesFromSerializers.
+
+export default interface AmsComposer {
+  id: number
+  first_name?: string
+  last_name?: string
+}

spec/types_from_serializers/ams/__snapshots__/interfaces_Ams__SongSerializer.snap

@@ -0,0 +1,10 @@
+// TypesFromSerializers CacheKey 7c65405710839d67b7e8f6a8578bfa2b
+//
+// DO NOT MODIFY: This file was automatically generated by TypesFromSerializers.
+import type AmsComposer from './Composer'
+
+export default interface AmsSong {
+  id: number
+  title?: string
+  composer: AmsComposer
+}

spec/types_from_serializers/ams/__snapshots__/interfaces_index.snap

@@ -0,0 +1,5 @@
+// TypesFromSerializers CacheKey fda33f0b08d157334e88f37f595d5aa1
+//
+// DO NOT MODIFY: This file was automatically generated by TypesFromSerializers.
+export type { default as AmsComposer } from './Ams/Composer'
+export type { default as AmsSong } from './Ams/Song'

spec/types_from_serializers/ams/generator_spec.rb

@@ -0,0 +1,85 @@
+require "vanilla/config/boot"
+require "vanilla/config/environment"
+
+describe "Generator" do
+  let(:output_dir) { Pathname.new File.expand_path("../support/generated", __dir__) }
+  let(:sample_dir) { Rails.root.join("app/frontend/types/serializers") }
+  let(:serializers) {
+    %w[
+      Ams::ComposerSerializer
+      Ams::SongSerializer
+    ]
+  }
+
+  def file_for(dir, name, ext)
+    dir.join("#{name.chomp("Serializer").gsub("::", "/")}.#{ext}")
+  end
+
+  def app_file_for(name, ext = "ts")
+    file_for(sample_dir, name, ext)
+  end
+
+  def output_file_for(name, ext = "ts")
+    file_for(output_dir, name, ext)
+  end
+
+  def expect_generator
+    expect(TypesFromSerializers)
+  end
+
+  def generate_serializers
+    receive(:serializer_interface_content).and_call_original
+  end
+
+  original_config = TypesFromSerializers::Config.new TypesFromSerializers.config.clone.to_h.transform_values(&:clone)
+
+  before do
+    TypesFromSerializers.instance_variable_set(:@config, original_config)
+
+    # Change the configuration to use a different directory.
+    TypesFromSerializers.config do |config|
+      config.base_serializers = ["Ams::BaseSerializer"]
+      config.output_dir = output_dir
+    end
+
+    output_dir.rmtree if output_dir.exist?
+  end
+
+  it "generates the files as expected" do
+    expect_generator.to generate_serializers.exactly(serializers.size).times
+    TypesFromSerializers.generate
+
+    # It does not generate routes that don't have `export: true`.
+    expect(output_file_for("AmsSerializer").exist?).to be false
+
+    # It generates one file per serializer.
+    serializers.each do |name|
+      output_file = output_file_for(name)
+      expect(output_file.read).to match_snapshot("interfaces_#{name.gsub("::", "__")}") # UPDATE_SNAPSHOTS="1" bin/rspec
+    end
+
+    # It generates an file that exports all interfaces.
+    index_file = output_dir.join("index.ts")
+    expect(index_file.exist?).to be true
+    expect(index_file.read).to match_snapshot("interfaces_index") # UPDATE_SNAPSHOTS="1" bin/rspec
+
+    # It does not render if generating again.
+    TypesFromSerializers.generate
+  end
+
+  it "has a rake task available" do
+    Rails.application.load_tasks
+    expect_generator.to generate_serializers.exactly(serializers.size).times
+    expect { Rake::Task["types_from_serializers:generate"].invoke }.not_to raise_error
+  end
+
+  describe "types mapping" do
+    it "maps citext type from SQL to string type in TypeScript" do
+      db_type = :citext
+
+      ts_type = TypesFromSerializers.config.sql_to_typescript_type_mapping[db_type]
+
+      expect(ts_type).to eq(:string)
+    end
+  end
+end

types_from_serializers/lib/types_from_serializers.rb

@@ -3,3 +3,4 @@
 require_relative "types_from_serializers/version"
 require_relative "types_from_serializers/dsl"
 require_relative "types_from_serializers/railtie"
+require_relative "types_from_serializers/ams"

types_from_serializers/lib/types_from_serializers/ams.rb

@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+require "active_support/concern"
+
+# Internal: A DSL to specify types for serializer attributes.
+module TypesFromSerializers
+  module Ams
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      # Override: Capture the name of the model related to the serializer.
+      #
+      # name - An alias for the internal object in the serializer.
+      # model - The name of an ActiveRecord model to infer types from the schema.
+      # types_from - The name of a TypeScript interface to infer types from.
+      def object_as(name, model: nil, types_from: nil)
+        # NOTE: Avoid taking memory for type information that won't be used.
+        if Rails.env.development?
+          model ||= name.is_a?(Symbol) ? name : try(:_serializer_model_name) || name
+          define_singleton_method(:_serializer_model_name) { model }
+          define_singleton_method(:_serializer_types_from) { types_from } if types_from
+        end
+      end
+
+      # Public: Shortcut for typing a serializer attribute.
+      #
+      # It specifies the type for a serializer method that will be defined
+      # immediately after calling this method.
+      def type(type, **options)
+        attribute type: type, **options
+      end
+
+      def prepare_attributes(transform_keys: nil, sort_by: nil)
+        attributes = _attributes_data.transform_values do |attribute|
+          {
+            value_from: attribute.name.to_s,
+            attribute: :method,
+            identifier: attribute.name == :id,
+          }
+        end
+
+        association_attributes = _reflections.transform_values do |association|
+          {
+            value_from: association.name.to_s,
+            association: one_association?(association) ? :one : :many,
+            serializer: association.options[:serializer],
+            identifier: association.name == :id,
+          }
+        end
+
+        attributes.merge!(association_attributes)
+      end
+
+    private
+
+      def one_association?(association)
+        # rubocop:disable Style/ClassEqualityComparison
+        return false if association.class.name == "ActiveModel::Serializer::HasManyReflection"
+        # rubocop:enable Style/ClassEqualityComparison
+
+        true
+      end
+
+      # Override: Remove unnecessary options in production, types are only
+      # used when generating code in development.
+      unless Rails.env.development?
+        def add_attribute(name, type: nil, optional: nil, **options)
+          super(name, **options)
+        end
+      end
+    end
+  end
+end

types_from_serializers/types_from_serializers.gemspec

@@ -20,6 +20,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "bundler", "~> 2"
   s.add_development_dependency "rake", "~> 13"
   s.add_development_dependency "rspec-given", "~> 3.8"
+  s.add_development_dependency "active_model_serializers", "~> 0.10.0"
   s.add_development_dependency "rspec-snapshot"
   s.add_development_dependency "simplecov", "< 0.18"
   s.add_development_dependency "standard", "~> 1.0"