From e95cfee0a6fa4ad0567eaa576ca5089f0a011dca Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Mon, 8 Jan 2024 17:08:58 +0900
Subject: [PATCH 01/16] skeleton task

---
 .../install_generator.rb                      | 21 +++++++++
 .../rake_task.rb                              | 46 +++++++++++++++++++
 spec/sample_app/Rakefile                      |  4 ++
 spec/sample_app/lib/tasks/task.rake           |  4 ++
 4 files changed, 75 insertions(+)
 create mode 100644 lib/generators/openapi_rails_typed_parameters/install_generator.rb
 create mode 100644 lib/openapi_rails_typed_parameters/rake_task.rb
 create mode 100644 spec/sample_app/Rakefile
 create mode 100644 spec/sample_app/lib/tasks/task.rake

diff --git a/lib/generators/openapi_rails_typed_parameters/install_generator.rb b/lib/generators/openapi_rails_typed_parameters/install_generator.rb
new file mode 100644
index 0000000..0882c92
--- /dev/null
+++ b/lib/generators/openapi_rails_typed_parameters/install_generator.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require 'rails'
+
+module OpenapiRailsTypedParameters
+  class InstallGenerator < Rails::Generators::Base
+    create_file 'lib/tasks/openapi_rails_typed_parameters.rake', <<~RUBY
+      begin
+        require 'openapi_rails_typed_parameters/rake_task'
+
+        OpenapiRailsTypedParameters::RakeTask.new do |task|
+          # Base path for RBS generation.
+          # default: Rails.root / 'sig/openapi_rails_typed_parameters'
+          # task.sig_root_dir = Rails.root / 'sig/openapi_rails_typed_parameters'
+        end
+      rescue LoadError
+        # failed to load openapi_rails_typed_parameters. Skip to load openapi_rails_typed_parameters tasks.
+      end
+    RUBY
+  end
+end
diff --git a/lib/openapi_rails_typed_parameters/rake_task.rb b/lib/openapi_rails_typed_parameters/rake_task.rb
new file mode 100644
index 0000000..e9a12a8
--- /dev/null
+++ b/lib/openapi_rails_typed_parameters/rake_task.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+require 'rake'
+require 'rake/tasklib'
+require 'rails'
+
+module OpenapiRailsTypedParameters
+  class RakeTask < Rake::TaskLib
+    attr_accessor :name
+    attr_writer :sig_root_dir
+
+    def initialize(name: :openapi_rails_typed_parameters, &block)
+      super()
+
+      @name = name
+      @sig_root_dir = Rails.root / 'sig/openapi_rails_typed_parameters'
+
+      block&.call(self)
+
+      def_generate
+    end
+
+    def def_generate
+      desc 'Generate RBS files for given OpenAPI schema'
+      task("#{name}:generate": :environment) do
+        require 'openapi_rails_typed_parameters'
+
+        Rails.application.eager_load!
+
+        config = OpenapiRailsTypedParameters.configuration
+        validator = OpenapiFirst.load(config.schema_path)
+        validator.operations.each do |operation|
+          path = Rails.application.routes.recognize_path(operation.path, method: operation.method)
+          controller_name = "#{path[:controller]}_controller".camelize
+          action_name = path[:action]
+          rbs = <<~RBS
+            class #{controller_name}
+              def self.typed_params_for: (:#{action_name}) -> nil
+            end
+          RBS
+          puts rbs
+        end
+      end
+    end
+  end
+end
diff --git a/spec/sample_app/Rakefile b/spec/sample_app/Rakefile
new file mode 100644
index 0000000..9dc8d07
--- /dev/null
+++ b/spec/sample_app/Rakefile
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+require_relative 'app'
+Rails.application.load_tasks
diff --git a/spec/sample_app/lib/tasks/task.rake b/spec/sample_app/lib/tasks/task.rake
new file mode 100644
index 0000000..f50fa39
--- /dev/null
+++ b/spec/sample_app/lib/tasks/task.rake
@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+require 'openapi_rails_typed_parameters/rake_task'
+OpenapiRailsTypedParameters::RakeTask.new

From 79eac3aefc5302e02ebf87ea4e721777e928c5d8 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 04:44:08 +0900
Subject: [PATCH 02/16] WIP: RBS generation

---
 lib/openapi_rails_typed_parameters.rb         |   1 +
 .../rake_task.rb                              |  22 +---
 .../type_generator.rb                         | 118 ++++++++++++++++++
 spec/openapi_rails_typed_parameters_spec.rb   |  18 +++
 spec/sample_app/app.rb                        |   8 +-
 spec/sample_app/schema.yml                    |  41 ++++++
 spec/type_generator_spec.rb                   |  21 ++++
 7 files changed, 210 insertions(+), 19 deletions(-)
 create mode 100644 lib/openapi_rails_typed_parameters/type_generator.rb
 create mode 100644 spec/type_generator_spec.rb

diff --git a/lib/openapi_rails_typed_parameters.rb b/lib/openapi_rails_typed_parameters.rb
index 7dbfb0c..7a1707b 100644
--- a/lib/openapi_rails_typed_parameters.rb
+++ b/lib/openapi_rails_typed_parameters.rb
@@ -4,4 +4,5 @@
 require_relative 'openapi_rails_typed_parameters/configuration'
 require_relative 'openapi_rails_typed_parameters/handler'
 require_relative 'openapi_rails_typed_parameters/railtie'
+require_relative 'openapi_rails_typed_parameters/type_generator'
 require_relative 'openapi_rails_typed_parameters/version'
diff --git a/lib/openapi_rails_typed_parameters/rake_task.rb b/lib/openapi_rails_typed_parameters/rake_task.rb
index e9a12a8..449b8d9 100644
--- a/lib/openapi_rails_typed_parameters/rake_task.rb
+++ b/lib/openapi_rails_typed_parameters/rake_task.rb
@@ -17,29 +17,15 @@ def initialize(name: :openapi_rails_typed_parameters, &block)
 
       block&.call(self)
 
-      def_generate
+      define_generate_task
     end
 
-    def def_generate
+    def define_generate_task
       desc 'Generate RBS files for given OpenAPI schema'
       task("#{name}:generate": :environment) do
         require 'openapi_rails_typed_parameters'
-
-        Rails.application.eager_load!
-
-        config = OpenapiRailsTypedParameters.configuration
-        validator = OpenapiFirst.load(config.schema_path)
-        validator.operations.each do |operation|
-          path = Rails.application.routes.recognize_path(operation.path, method: operation.method)
-          controller_name = "#{path[:controller]}_controller".camelize
-          action_name = path[:action]
-          rbs = <<~RBS
-            class #{controller_name}
-              def self.typed_params_for: (:#{action_name}) -> nil
-            end
-          RBS
-          puts rbs
-        end
+        type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
+        type_generator.generate_rbs(rbs_file_path: '')
       end
     end
   end
diff --git a/lib/openapi_rails_typed_parameters/type_generator.rb b/lib/openapi_rails_typed_parameters/type_generator.rb
new file mode 100644
index 0000000..a443507
--- /dev/null
+++ b/lib/openapi_rails_typed_parameters/type_generator.rb
@@ -0,0 +1,118 @@
+
+module OpenapiRailsTypedParameters
+  class TypeGenerator
+    def generate_rbs(rbs_file_path:)
+
+      config = OpenapiRailsTypedParameters.configuration
+      validator = OpenapiFirst.load(config.schema_path)
+
+      return <<~RBS
+        #{parameter_definitions(validator:)}
+
+        #{controller_definitions(validator:)}
+      RBS
+    end
+
+    private
+
+    def operation_to_type_name(operation:)
+      # TODO: sequence number for duped name
+      verb = operation.method
+      path =
+        operation.
+        path.
+        scan(/[\w_]+/).
+        join('_')
+      return "#{verb}_#{path}_params"
+    end
+
+    def parameter_definitions(validator:)
+      lines = []
+
+      operations = validator.operations
+      operations.each do |operation|
+        type_name = operation_to_type_name(operation:)
+
+        path_params_rbs =
+          operation.
+          query_parameters&.
+          parameters.
+          then { _1 || []}.
+          map { |param|
+            type = param.schema['type']
+            optional = param.required? ? '' : '?'
+            "#{param.name}: #{type}#{optional}"
+          }.
+          join(",\n")
+
+        query_params_rbs =
+          operation.
+          query_parameters&.
+          parameters.
+          then { _1 || []}.
+          map { |param|
+            type = param.schema['type'].camelize
+            optional = param.required? ? '' : '?'
+            "#{param.name}: #{type}#{optional}"
+          }.
+          join(",\n")
+
+        lines << <<~RBS
+          type #{type_name} = {
+            path_params: {
+              #{path_params_rbs}
+            },
+            query_params: {
+              #{query_params_rbs}
+            },
+            body: {
+            },
+            valid: bool
+          }
+        RBS
+      end
+
+      return lines.join("\n")
+    end
+
+    def controller_definitions(validator:)
+      Rails.application.eager_load!
+      route_inspector = ActionDispatch::Routing::RoutesInspector.new(Rails.application.routes.routes)
+      journy_routes = route_inspector.instance_variable_get(:@routes)
+
+      # @type var params_definitions: Hash[String, Hash[String, untyped]]
+      params_definitions = {}
+      validator.operations.each do |operation|
+        puts "Find: #{operation.method} #{operation.path}"
+        path = journy_routes.find { |route|
+          route.path.match?(operation.path) && route.verb.downcase.to_sym == operation.method.to_sym
+        }
+
+        # path not found
+        next unless path
+
+        controller_name = "#{path.defaults[:controller]}_controller".camelize
+        action_name = path.defaults[:action]
+
+        params_definitions[controller_name] ||= {}
+        params_definitions[controller_name][action_name] = operation
+
+      end
+
+      lines = []
+      params_definitions.map do |controller_name, action_definitions|
+        lines << "class #{controller_name}"
+        action_definitions.each.with_index do |(action_name, operation), i|
+          type_name = operation_to_type_name(operation:)
+          if i == 0
+            lines << "  def self.typed_params_for: (:#{action_name}) -> #{type_name}"
+          else
+            lines << "                           | (:#{action_name}) -> #{type_name}"
+          end
+        end
+        lines << "end"
+      end
+      return lines.join("\n")
+    end
+  end
+end
diff --git a/spec/openapi_rails_typed_parameters_spec.rb b/spec/openapi_rails_typed_parameters_spec.rb
index 4d1d0f5..ac7910d 100644
--- a/spec/openapi_rails_typed_parameters_spec.rb
+++ b/spec/openapi_rails_typed_parameters_spec.rb
@@ -44,4 +44,22 @@
       end
     end
   end
+
+  describe 'Path parameters'do
+    context 'with valid query' do
+      it 'returns response' do
+        get '/users/123'
+        expected = {
+          path_params: {
+            id: 123
+          },
+          query_params: {},
+          body: nil,
+          valid: true
+        }
+        actual = JSON.parse(response.body, symbolize_names: true)
+        expect(actual).to eq expected
+      end
+    end
+  end
 end
diff --git a/spec/sample_app/app.rb b/spec/sample_app/app.rb
index e01f1ed..4bcf9ef 100644
--- a/spec/sample_app/app.rb
+++ b/spec/sample_app/app.rb
@@ -33,7 +33,13 @@ def index
   end
 
   def show
-    render json: {}
+    typed_params = typed_params_for(:show)
+    typed_params.validate!
+    render json: typed_params.to_h
+  rescue OpenapiFirst::RequestInvalidError => e
+    render json: {
+      message: e.message
+    }, status: :bad_request
   end
 
   def create
diff --git a/spec/sample_app/schema.yml b/spec/sample_app/schema.yml
index f038e9a..0582556 100644
--- a/spec/sample_app/schema.yml
+++ b/spec/sample_app/schema.yml
@@ -24,3 +24,44 @@ paths:
           required: false
           schema:
             type: integer
+    post:
+      requestBody:
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                - name: role
+                  required: true
+                  schema:
+                    type: string
+                    enum: [ admin, maintainer ]
+  /users/{user_id}:
+    get:
+      parameters:
+        - name: id
+          in: path
+          required: true
+          schema:
+            type: integer
+  /users/{user_id}/articles:
+    get:
+      parameters:
+        - name: user_id
+          in: path
+          required: true
+          schema:
+            type: integer
+  /users/{user_id}/articles/{article_id}:
+    get:
+      parameters:
+        - name: user_id
+          in: path
+          required: true
+          schema:
+            type: integer
+        - name: article_id
+          in: path
+          required: true
+          schema:
+            type: integer
diff --git a/spec/type_generator_spec.rb b/spec/type_generator_spec.rb
new file mode 100644
index 0000000..7bf9637
--- /dev/null
+++ b/spec/type_generator_spec.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe OpenapiRailsTypedParameters::TypeGenerator do
+  describe 'generate_rbs' do
+    context 'a' do
+      it 'generates correct RBS file' do
+        type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
+        actual = type_generator.generate_rbs(rbs_file_path: '')
+        expected = <<~RBS
+          class UsersController
+            def self.typed_params_for: (:index) -> nil
+          end
+        RBS
+
+        expect(actual).to eq(expected)
+      end
+    end
+  end
+end

From df40b8023a5c47d435831ef8200db8b41406042d Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 17:07:07 +0900
Subject: [PATCH 03/16] rake task

---
 .../rake_task.rb                              | 25 ++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/lib/openapi_rails_typed_parameters/rake_task.rb b/lib/openapi_rails_typed_parameters/rake_task.rb
index 449b8d9..47bebb2 100644
--- a/lib/openapi_rails_typed_parameters/rake_task.rb
+++ b/lib/openapi_rails_typed_parameters/rake_task.rb
@@ -25,8 +25,31 @@ def define_generate_task
       task("#{name}:generate": :environment) do
         require 'openapi_rails_typed_parameters'
         type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
-        type_generator.generate_rbs(rbs_file_path: '')
+        rbs = type_generator.generate_rbs
+        file_path = File.join(@sig_root_dir, 'action_controller.rbs')
+
+        options = parse_options(argv: ARGV)
+
+        if File.exist?(file_path) && options[:force] == false
+          abort "RBS file '#{file_path}' already exists. use `--force` option to overwrite."
+        else
+          File.write(file_path, rbs)
+        end
       end
     end
+
+    private
+
+    def parse_options(argv:)
+      options = {}
+
+      option_parser = OptionParser.new
+      option_parser.banner = 'Usage: openapi_rails_typed_parameters:generate [options]'
+      option_parser.on('-f', '--force', FalseClass, 'Force overwrite RBS file if it\'s already exists.')
+      args = option_parser.order(argv)
+      option_parser.parse(args, into: options)
+
+      options
+    end
   end
 end

From 5d5d4123b29dc3fae5ce82a8ec85e73f5e8dfbed Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 17:07:37 +0900
Subject: [PATCH 04/16] format

---
 .../type_generator.rb                         | 65 +++++++++----------
 spec/openapi_rails_typed_parameters_spec.rb   |  2 +-
 spec/type_generator_spec.rb                   |  2 +-
 3 files changed, 34 insertions(+), 35 deletions(-)

diff --git a/lib/openapi_rails_typed_parameters/type_generator.rb b/lib/openapi_rails_typed_parameters/type_generator.rb
index a443507..4d75df5 100644
--- a/lib/openapi_rails_typed_parameters/type_generator.rb
+++ b/lib/openapi_rails_typed_parameters/type_generator.rb
@@ -1,12 +1,12 @@
+# frozen_string_literal: true
 
 module OpenapiRailsTypedParameters
   class TypeGenerator
-    def generate_rbs(rbs_file_path:)
-
+    def generate_rbs
       config = OpenapiRailsTypedParameters.configuration
       validator = OpenapiFirst.load(config.schema_path)
 
-      return <<~RBS
+      <<~RBS
         #{parameter_definitions(validator:)}
 
         #{controller_definitions(validator:)}
@@ -19,11 +19,11 @@ def operation_to_type_name(operation:)
       # TODO: sequence number for duped name
       verb = operation.method
       path =
-        operation.
-        path.
-        scan(/[\w_]+/).
-        join('_')
-      return "#{verb}_#{path}_params"
+        operation
+        .path
+        .scan(/[\w_]+/)
+        .join('_')
+      "#{verb}_#{path}_params"
     end
 
     def parameter_definitions(validator:)
@@ -34,28 +34,28 @@ def parameter_definitions(validator:)
         type_name = operation_to_type_name(operation:)
 
         path_params_rbs =
-          operation.
-          query_parameters&.
-          parameters.
-          then { _1 || []}.
-          map { |param|
+          operation
+          .query_parameters
+          &.parameters
+          .then { _1 || [] }
+          .map do |param|
             type = param.schema['type']
             optional = param.required? ? '' : '?'
             "#{param.name}: #{type}#{optional}"
-          }.
-          join(",\n")
+          end
+          .join(",\n")
 
         query_params_rbs =
-          operation.
-          query_parameters&.
-          parameters.
-          then { _1 || []}.
-          map { |param|
+          operation
+          .query_parameters
+          &.parameters
+          .then { _1 || [] }
+          .map do |param|
             type = param.schema['type'].camelize
             optional = param.required? ? '' : '?'
             "#{param.name}: #{type}#{optional}"
-          }.
-          join(",\n")
+          end
+          .join(",\n")
 
         lines << <<~RBS
           type #{type_name} = {
@@ -72,7 +72,7 @@ def parameter_definitions(validator:)
         RBS
       end
 
-      return lines.join("\n")
+      lines.join("\n")
     end
 
     def controller_definitions(validator:)
@@ -84,9 +84,9 @@ def controller_definitions(validator:)
       params_definitions = {}
       validator.operations.each do |operation|
         puts "Find: #{operation.method} #{operation.path}"
-        path = journy_routes.find { |route|
+        path = journy_routes.find do |route|
           route.path.match?(operation.path) && route.verb.downcase.to_sym == operation.method.to_sym
-        }
+        end
 
         # path not found
         next unless path
@@ -96,7 +96,6 @@ def controller_definitions(validator:)
 
         params_definitions[controller_name] ||= {}
         params_definitions[controller_name][action_name] = operation
-
       end
 
       lines = []
@@ -104,15 +103,15 @@ def controller_definitions(validator:)
         lines << "class #{controller_name}"
         action_definitions.each.with_index do |(action_name, operation), i|
           type_name = operation_to_type_name(operation:)
-          if i == 0
-            lines << "  def self.typed_params_for: (:#{action_name}) -> #{type_name}"
-          else
-            lines << "                           | (:#{action_name}) -> #{type_name}"
-          end
+          lines << if i.zero?
+                     "  def self.typed_params_for: (:#{action_name}) -> #{type_name}"
+                   else
+                     "                           | (:#{action_name}) -> #{type_name}"
+                   end
         end
-        lines << "end"
+        lines << 'end'
       end
-      return lines.join("\n")
+      lines.join("\n")
     end
   end
 end
diff --git a/spec/openapi_rails_typed_parameters_spec.rb b/spec/openapi_rails_typed_parameters_spec.rb
index ac7910d..4e06998 100644
--- a/spec/openapi_rails_typed_parameters_spec.rb
+++ b/spec/openapi_rails_typed_parameters_spec.rb
@@ -45,7 +45,7 @@
     end
   end
 
-  describe 'Path parameters'do
+  describe 'Path parameters' do
     context 'with valid query' do
       it 'returns response' do
         get '/users/123'
diff --git a/spec/type_generator_spec.rb b/spec/type_generator_spec.rb
index 7bf9637..643aaab 100644
--- a/spec/type_generator_spec.rb
+++ b/spec/type_generator_spec.rb
@@ -7,7 +7,7 @@
     context 'a' do
       it 'generates correct RBS file' do
         type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
-        actual = type_generator.generate_rbs(rbs_file_path: '')
+        actual = type_generator.generate_rbs
         expected = <<~RBS
           class UsersController
             def self.typed_params_for: (:index) -> nil

From ed69e5cd6bb94a5cdf2a2067a241f0ae3b625bb0 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 17:12:28 +0900
Subject: [PATCH 05/16] sort require order

---
 .rubocop.yml                                    | 4 ++++
 lib/openapi_rails_typed_parameters/rake_task.rb | 3 ++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/.rubocop.yml b/.rubocop.yml
index 962e0df..eea3727 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -39,3 +39,7 @@ Style/FrozenStringLiteralComment:
   Enabled: true
   EnforcedStyle: always_true
   SafeAutoCorrect: true
+
+Style/RequireOrder:
+  Enabled: true
+  SafeAutoCorrect: true
diff --git a/lib/openapi_rails_typed_parameters/rake_task.rb b/lib/openapi_rails_typed_parameters/rake_task.rb
index 47bebb2..caa82cb 100644
--- a/lib/openapi_rails_typed_parameters/rake_task.rb
+++ b/lib/openapi_rails_typed_parameters/rake_task.rb
@@ -1,8 +1,9 @@
 # frozen_string_literal: true
 
+require 'optparse'
+require 'rails'
 require 'rake'
 require 'rake/tasklib'
-require 'rails'
 
 module OpenapiRailsTypedParameters
   class RakeTask < Rake::TaskLib

From bdc179ca68c46bf601f3e1fd2a080ca150d59311 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 21:55:52 +0900
Subject: [PATCH 06/16] test formatted RBSs

---
 .../type_generator.rb                         | 90 +++++++++++--------
 spec/type_generator_spec.rb                   | 34 +++++--
 2 files changed, 82 insertions(+), 42 deletions(-)

diff --git a/lib/openapi_rails_typed_parameters/type_generator.rb b/lib/openapi_rails_typed_parameters/type_generator.rb
index 4d75df5..48f5b86 100644
--- a/lib/openapi_rails_typed_parameters/type_generator.rb
+++ b/lib/openapi_rails_typed_parameters/type_generator.rb
@@ -1,33 +1,38 @@
 # frozen_string_literal: true
 
+require 'rbs'
+
 module OpenapiRailsTypedParameters
   class TypeGenerator
-    def generate_rbs
-      config = OpenapiRailsTypedParameters.configuration
-      validator = OpenapiFirst.load(config.schema_path)
+    private attr_accessor :config
+    private attr_accessor :validator
 
-      <<~RBS
-        #{parameter_definitions(validator:)}
+    def initialize
+      @config = OpenapiRailsTypedParameters.configuration
+      @validator = OpenapiFirst.load(@config.schema_path)
+    end
 
-        #{controller_definitions(validator:)}
+    def generate_rbs
+      rbs = <<~RBS
+        #{generate_parameter_definitions}
+        #{generate_controller_definitions}
       RBS
+      return format(rbs)
     end
 
-    private
-
     def operation_to_type_name(operation:)
-      # TODO: sequence number for duped name
+      # TODO: Use same naming as Rails path helper
       verb = operation.method
       path =
         operation
         .path
         .scan(/[\w_]+/)
         .join('_')
-      "#{verb}_#{path}_params"
+      return "#{verb}_#{path}"
     end
 
-    def parameter_definitions(validator:)
-      lines = []
+    def generate_parameter_definitions
+      definitions = []
 
       operations = validator.operations
       operations.each do |operation|
@@ -35,11 +40,11 @@ def parameter_definitions(validator:)
 
         path_params_rbs =
           operation
-          .query_parameters
+          .path_parameters
           &.parameters
           .then { _1 || [] }
           .map do |param|
-            type = param.schema['type']
+            type = param.schema['type'].camelize
             optional = param.required? ? '' : '?'
             "#{param.name}: #{type}#{optional}"
           end
@@ -57,25 +62,22 @@ def parameter_definitions(validator:)
           end
           .join(",\n")
 
-        lines << <<~RBS
+        definitions << <<~RBS
           type #{type_name} = {
-            path_params: {
-              #{path_params_rbs}
-            },
-            query_params: {
-              #{query_params_rbs}
-            },
-            body: {
-            },
+            path_params: { #{path_params_rbs} },
+            query_params: { #{query_params_rbs} },
+            body: __todo__,
             valid: bool
           }
         RBS
       end
 
-      lines.join("\n")
+      # return 'type hoge = {hi: Integer}'
+      rbs = format(definitions.join("\n"))
+      return rbs
     end
 
-    def controller_definitions(validator:)
+    def generate_controller_definitions
       Rails.application.eager_load!
       route_inspector = ActionDispatch::Routing::RoutesInspector.new(Rails.application.routes.routes)
       journy_routes = route_inspector.instance_variable_get(:@routes)
@@ -99,19 +101,33 @@ def controller_definitions(validator:)
       end
 
       lines = []
-      params_definitions.map do |controller_name, action_definitions|
-        lines << "class #{controller_name}"
-        action_definitions.each.with_index do |(action_name, operation), i|
-          type_name = operation_to_type_name(operation:)
-          lines << if i.zero?
-                     "  def self.typed_params_for: (:#{action_name}) -> #{type_name}"
-                   else
-                     "                           | (:#{action_name}) -> #{type_name}"
-                   end
+      params_definitions
+        .sort_by { |controller_name, _| controller_name }
+        .map do |controller_name, action_definitions|
+          lines << "class #{controller_name}"
+          action_definitions
+            .sort_by { |action_name, _| action_name }
+            .each.with_index do |(action_name, operation), i|
+            type_name = operation_to_type_name(operation:)
+            lines << if i.zero?
+                       "  def self.typed_params_for: (:#{action_name}) -> #{type_name}"
+                     else
+                       "                           | (:#{action_name}) -> #{type_name}"
+                     end
+          end
+          lines << 'end'
         end
-        lines << 'end'
-      end
-      lines.join("\n")
+      return format(lines.join("\n"))
+    end
+
+    def format(rbs)
+      signature = RBS::Parser.parse_signature(rbs)
+      stream = StringIO.new
+      writer = RBS::Writer.new(out: stream)
+      writer.write(signature[1] + signature[2])
+      formatted = stream.string
+      stream.close
+      return formatted
     end
   end
 end
diff --git a/spec/type_generator_spec.rb b/spec/type_generator_spec.rb
index 643aaab..7b7b08f 100644
--- a/spec/type_generator_spec.rb
+++ b/spec/type_generator_spec.rb
@@ -4,17 +4,41 @@
 
 RSpec.describe OpenapiRailsTypedParameters::TypeGenerator do
   describe 'generate_rbs' do
-    context 'a' do
-      it 'generates correct RBS file' do
+    context 'Parameter types' do
+      it 'generates correct types' do
         type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
-        actual = type_generator.generate_rbs
+        actual = type_generator.generate_parameter_definitions
+        expected = <<~RBS
+          type get_users = {
+            path_params: {
+            },
+            query_params: {
+              role: String,
+              minimum: Integer?,
+              maximum: Integer?
+            },
+            body: __todo__,
+            valid: bool
+          }
+        RBS
+
+        expect(actual).to eq(type_generator.format(expected))
+      end
+    end
+
+    context 'Controller actions' do
+      it 'generates correct actions' do
+        type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
+        actual = type_generator.generate_controller_definitions
         expected = <<~RBS
           class UsersController
-            def self.typed_params_for: (:index) -> nil
+            def self.typed_params_for: (:create) -> post_users
+                                     | (:index) -> get_users
+                                     | (:show) -> get_users_user_id
           end
         RBS
 
-        expect(actual).to eq(expected)
+        expect(actual).to eq(type_generator.format(expected))
       end
     end
   end

From bc898cf8fc04e9304057155fb7bae2c98225e598 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sat, 27 Jan 2024 21:56:00 +0900
Subject: [PATCH 07/16] rubocop

---
 .rubocop.yml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/.rubocop.yml b/.rubocop.yml
index eea3727..d800eb3 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -43,3 +43,10 @@ Style/FrozenStringLiteralComment:
 Style/RequireOrder:
   Enabled: true
   SafeAutoCorrect: true
+
+Style/AccessModifierDeclarations:
+  Enabled: true
+  EnforcedStyle: inline
+
+Style/RedundantReturn:
+  Enabled: false

From da5cd680fa102418ec5998cc45fb6010ded2d974 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sun, 28 Jan 2024 02:19:26 +0900
Subject: [PATCH 08/16] spec

---
 spec/openapi_rails_typed_parameters_spec.rb | 2 +-
 spec/sample_app/app.rb                      | 1 +
 spec/spec_helper.rb                         | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/spec/openapi_rails_typed_parameters_spec.rb b/spec/openapi_rails_typed_parameters_spec.rb
index 4e06998..97f0eea 100644
--- a/spec/openapi_rails_typed_parameters_spec.rb
+++ b/spec/openapi_rails_typed_parameters_spec.rb
@@ -51,7 +51,7 @@
         get '/users/123'
         expected = {
           path_params: {
-            id: 123
+            user_id: 123
           },
           query_params: {},
           body: nil,
diff --git a/spec/sample_app/app.rb b/spec/sample_app/app.rb
index 4bcf9ef..741ecf0 100644
--- a/spec/sample_app/app.rb
+++ b/spec/sample_app/app.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'action_controller/railtie'
+require_relative '../../lib/openapi_rails_typed_parameters'
 
 class SampleApp < Rails::Application
   config.active_support.cache_format_version = 7.0
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 4b8bdf7..ee9b1e5 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
 require 'openapi_rails_typed_parameters'
-require 'sample_app/app'
 require 'rspec/rails'
+require 'sample_app/app'
 
 RSpec.configure do |config|
   # Enable flags like --only-failures and --next-failure

From 489e42a76200053c1a244b582091314b59fea2ae Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sun, 28 Jan 2024 02:19:49 +0900
Subject: [PATCH 09/16] setup steep

---
 Steepfile                |  21 +++
 rbs_collection.lock.yaml | 280 +++++++++++++++++++++++++++++++++++++++
 rbs_collection.yaml      |  19 +++
 3 files changed, 320 insertions(+)
 create mode 100644 Steepfile
 create mode 100644 rbs_collection.lock.yaml
 create mode 100644 rbs_collection.yaml

diff --git a/Steepfile b/Steepfile
new file mode 100644
index 0000000..e9fcc21
--- /dev/null
+++ b/Steepfile
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+D = Steep::Diagnostic
+
+target :lib do
+  signature 'sig'
+
+  check 'lib'
+  check 'Gemfile'
+  check 'Rakefile'
+  # configure_code_diagnostics(D::Ruby.default)      # `default` diagnostics setting (applies by default)
+  # configure_code_diagnostics(D::Ruby.strict)       # `strict` diagnostics setting
+  # configure_code_diagnostics(D::Ruby.lenient)      # `lenient` diagnostics setting
+  # configure_code_diagnostics(D::Ruby.silent)       # `silent` diagnostics setting
+end
+
+target :spec do
+  signature 'sig'
+
+  check 'spec'
+end
diff --git a/rbs_collection.lock.yaml b/rbs_collection.lock.yaml
new file mode 100644
index 0000000..924f73a
--- /dev/null
+++ b/rbs_collection.lock.yaml
@@ -0,0 +1,280 @@
+---
+path: ".gem_rbs_collection"
+gems:
+- name: abbrev
+  version: '0'
+  source:
+    type: stdlib
+- name: actionpack
+  version: '6.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: actionview
+  version: '6.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: activesupport
+  version: '7.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: ast
+  version: '2.4'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: base64
+  version: '0'
+  source:
+    type: stdlib
+- name: bigdecimal
+  version: '0'
+  source:
+    type: stdlib
+- name: cgi
+  version: '0'
+  source:
+    type: stdlib
+- name: concurrent-ruby
+  version: '1.1'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: connection_pool
+  version: '2.4'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: csv
+  version: '0'
+  source:
+    type: stdlib
+- name: date
+  version: '0'
+  source:
+    type: stdlib
+- name: erb
+  version: '0'
+  source:
+    type: stdlib
+- name: fileutils
+  version: '0'
+  source:
+    type: stdlib
+- name: forwardable
+  version: '0'
+  source:
+    type: stdlib
+- name: i18n
+  version: '1.10'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: io-console
+  version: '0'
+  source:
+    type: stdlib
+- name: json
+  version: '0'
+  source:
+    type: stdlib
+- name: listen
+  version: '3.2'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: logger
+  version: '0'
+  source:
+    type: stdlib
+- name: minitest
+  version: '0'
+  source:
+    type: stdlib
+- name: monitor
+  version: '0'
+  source:
+    type: stdlib
+- name: mutex_m
+  version: '0'
+  source:
+    type: stdlib
+- name: nokogiri
+  version: '1.11'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: openapi_parameters
+  version: 0.3.2
+  source:
+    type: rubygems
+- name: optparse
+  version: '0'
+  source:
+    type: stdlib
+- name: parallel
+  version: '1.20'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: parser
+  version: '3.2'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: pathname
+  version: '0'
+  source:
+    type: stdlib
+- name: rack
+  version: '2.2'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rails-dom-testing
+  version: '2.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: railties
+  version: '6.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rainbow
+  version: '3.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rake
+  version: '13.0'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rbs
+  version: 3.4.1
+  source:
+    type: rubygems
+- name: rdoc
+  version: '0'
+  source:
+    type: stdlib
+- name: regexp_parser
+  version: '2.8'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rubocop
+  version: '1.57'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: rubocop-ast
+  version: '1.30'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: securerandom
+  version: '0'
+  source:
+    type: stdlib
+- name: singleton
+  version: '0'
+  source:
+    type: stdlib
+- name: steep
+  version: 1.6.0
+  source:
+    type: rubygems
+- name: strscan
+  version: '0'
+  source:
+    type: stdlib
+- name: tempfile
+  version: '0'
+  source:
+    type: stdlib
+- name: thor
+  version: '1.2'
+  source:
+    type: git
+    name: ruby/gem_rbs_collection
+    revision: 846c09971455f0e144cef2f5a6c9fe6d8905d3e1
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    repo_dir: gems
+- name: time
+  version: '0'
+  source:
+    type: stdlib
+- name: timeout
+  version: '0'
+  source:
+    type: stdlib
+- name: tsort
+  version: '0'
+  source:
+    type: stdlib
+- name: uri
+  version: '0'
+  source:
+    type: stdlib
+gemfile_lock_path: Gemfile.lock
diff --git a/rbs_collection.yaml b/rbs_collection.yaml
new file mode 100644
index 0000000..d6f0582
--- /dev/null
+++ b/rbs_collection.yaml
@@ -0,0 +1,19 @@
+# Download sources
+sources:
+  - type: git
+    name: ruby/gem_rbs_collection
+    remote: https://github.com/ruby/gem_rbs_collection.git
+    revision: main
+    repo_dir: gems
+
+# You can specify local directories as sources also.
+# - type: local
+#   path: path/to/your/local/repository
+
+# A directory to install the downloaded RBSs
+path: .gem_rbs_collection
+
+gems:
+  - name: rbs
+  - name: pathname
+  - name: logger

From 4d46c187bef6fe12c086d331778631141244bd34 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sun, 28 Jan 2024 02:19:55 +0900
Subject: [PATCH 10/16] fix

---
 spec/sample_app/schema.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spec/sample_app/schema.yml b/spec/sample_app/schema.yml
index 0582556..61b4007 100644
--- a/spec/sample_app/schema.yml
+++ b/spec/sample_app/schema.yml
@@ -39,7 +39,7 @@ paths:
   /users/{user_id}:
     get:
       parameters:
-        - name: id
+        - name: user_id
           in: path
           required: true
           schema:

From 80fc8899bf3a0a3385af3ea5648dc1878741c581 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sun, 28 Jan 2024 02:20:22 +0900
Subject: [PATCH 11/16] wip

---
 .../type_generator.rb                         | 11 +++++--
 spec/type_generator_spec.rb                   | 30 +++++++++++++++++--
 2 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/lib/openapi_rails_typed_parameters/type_generator.rb b/lib/openapi_rails_typed_parameters/type_generator.rb
index 48f5b86..94ec059 100644
--- a/lib/openapi_rails_typed_parameters/type_generator.rb
+++ b/lib/openapi_rails_typed_parameters/type_generator.rb
@@ -73,7 +73,7 @@ def generate_parameter_definitions
       end
 
       # return 'type hoge = {hi: Integer}'
-      rbs = format(definitions.join("\n"))
+      rbs = format(definitions.join)
       return rbs
     end
 
@@ -117,7 +117,8 @@ def generate_controller_definitions
           end
           lines << 'end'
         end
-      return format(lines.join("\n"))
+      rbs = format(lines.join("\n"))
+      return rbs
     end
 
     def format(rbs)
@@ -125,7 +126,11 @@ def format(rbs)
       stream = StringIO.new
       writer = RBS::Writer.new(out: stream)
       writer.write(signature[1] + signature[2])
-      formatted = stream.string
+      formatted =
+        stream
+        .string
+        # remove multiple newlines
+        .gsub(/\n{2,}/, "\n")
       stream.close
       return formatted
     end
diff --git a/spec/type_generator_spec.rb b/spec/type_generator_spec.rb
index 7b7b08f..4a825fd 100644
--- a/spec/type_generator_spec.rb
+++ b/spec/type_generator_spec.rb
@@ -6,12 +6,14 @@
   describe 'generate_rbs' do
     context 'Parameter types' do
       it 'generates correct types' do
+        OpenapiRailsTypedParameters.configure do |_config|
+          # TODO
+        end
         type_generator = OpenapiRailsTypedParameters::TypeGenerator.new
         actual = type_generator.generate_parameter_definitions
         expected = <<~RBS
           type get_users = {
-            path_params: {
-            },
+            path_params: { },
             query_params: {
               role: String,
               minimum: Integer?,
@@ -20,6 +22,30 @@
             body: __todo__,
             valid: bool
           }
+          type post_users = {
+            path_params: { },
+            query_params: { },
+            body: __todo__,
+            valid: bool
+          }
+          type get_users_user_id = {
+            path_params: { user_id: Integer },
+            query_params: { },
+            body: __todo__,
+            valid: bool
+          }
+          type get_users_user_id_articles = {
+            path_params: { user_id: Integer },
+            query_params: { },
+            body: __todo__,
+            valid: bool
+          }
+          type get_users_user_id_articles_article_id = {
+            path_params: { user_id: Integer, article_id: Integer },
+            query_params: { },
+            body: __todo__,
+            valid: bool
+          }
         RBS
 
         expect(actual).to eq(type_generator.format(expected))

From 402c3e30d2c77ff11d39e5e64965d1519c2edf50 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Sun, 28 Jan 2024 02:21:23 +0900
Subject: [PATCH 12/16] rubocop

---
 lib/openapi_rails_typed_parameters/rake_task.rb | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/openapi_rails_typed_parameters/rake_task.rb b/lib/openapi_rails_typed_parameters/rake_task.rb
index caa82cb..6348b2e 100644
--- a/lib/openapi_rails_typed_parameters/rake_task.rb
+++ b/lib/openapi_rails_typed_parameters/rake_task.rb
@@ -39,9 +39,7 @@ def define_generate_task
       end
     end
 
-    private
-
-    def parse_options(argv:)
+    private def parse_options(argv:)
       options = {}
 
       option_parser = OptionParser.new

From 2173dbab1c2fb1b4f336615bf1a1fb266e5fb18b Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Mon, 29 Jan 2024 03:52:45 +0900
Subject: [PATCH 13/16] RBS

---
 rbs_collection.lock.yaml               |  4 ++++
 sig/configuration.rbs                  |  5 +++++
 sig/handler.rbs                        |  6 ++++++
 sig/install_generator.rbs              |  2 ++
 sig/openapi_rails_typed_parameters.rbs |  7 ++++++-
 sig/railtie.rbs                        |  2 ++
 sig/rake_task.rbs                      | 10 ++++++++++
 sig/type_generator.rbs                 | 12 ++++++++++++
 sig/typed_parameters.rbs               | 17 +++++++++++++++++
 9 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 sig/configuration.rbs
 create mode 100644 sig/handler.rbs
 create mode 100644 sig/install_generator.rbs
 create mode 100644 sig/railtie.rbs
 create mode 100644 sig/rake_task.rbs
 create mode 100644 sig/type_generator.rbs
 create mode 100644 sig/typed_parameters.rbs

diff --git a/rbs_collection.lock.yaml b/rbs_collection.lock.yaml
index 924f73a..42fb757 100644
--- a/rbs_collection.lock.yaml
+++ b/rbs_collection.lock.yaml
@@ -141,6 +141,10 @@ gems:
   version: '0'
   source:
     type: stdlib
+- name: orthoses
+  version: 1.13.0
+  source:
+    type: rubygems
 - name: parallel
   version: '1.20'
   source:
diff --git a/sig/configuration.rbs b/sig/configuration.rbs
new file mode 100644
index 0000000..bbc3340
--- /dev/null
+++ b/sig/configuration.rbs
@@ -0,0 +1,5 @@
+class OpenapiRailsTypedParameters::Configuration
+  @schema_path: String
+  attr_accessor schema_path: String
+  private def initialize: () -> void
+end
diff --git a/sig/handler.rbs b/sig/handler.rbs
new file mode 100644
index 0000000..37035b8
--- /dev/null
+++ b/sig/handler.rbs
@@ -0,0 +1,6 @@
+class OpenapiRailsTypedParameters::Handler
+  attr_accessor self.configuration: OpenapiRailsTypedParameters::Configuration
+  attr_accessor self.validator: untyped
+  def self.build_validator: () -> __todo__
+  def self.build_validator_if_needed: () -> __todo__
+end
diff --git a/sig/install_generator.rbs b/sig/install_generator.rbs
new file mode 100644
index 0000000..725d6b1
--- /dev/null
+++ b/sig/install_generator.rbs
@@ -0,0 +1,2 @@
+class OpenapiRailsTypedParameters::InstallGenerator < ::Rails::Generators::Base
+end
diff --git a/sig/openapi_rails_typed_parameters.rbs b/sig/openapi_rails_typed_parameters.rbs
index a55d3d1..22bde21 100644
--- a/sig/openapi_rails_typed_parameters.rbs
+++ b/sig/openapi_rails_typed_parameters.rbs
@@ -1,4 +1,9 @@
 module OpenapiRailsTypedParameters
+  @@configuration: untyped
+
+  def self.configuration: () -> OpenapiRailsTypedParameters::Configuration
+
+  def self.configure: () -> nil
+
   VERSION: String
-  # See the writing guide of rbs: https://github.com/ruby/rbs#guides
 end
diff --git a/sig/railtie.rbs b/sig/railtie.rbs
new file mode 100644
index 0000000..73e6a9e
--- /dev/null
+++ b/sig/railtie.rbs
@@ -0,0 +1,2 @@
+class OpenapiRailsTypedParameters::Railtie < ::Rails::Railtie
+end
diff --git a/sig/rake_task.rbs b/sig/rake_task.rbs
new file mode 100644
index 0000000..bb2f7e3
--- /dev/null
+++ b/sig/rake_task.rbs
@@ -0,0 +1,10 @@
+class OpenapiRailsTypedParameters::RakeTask < ::Rake::TaskLib
+  @name: String
+  @sig_root_dir: String
+  attr_accessor name: String
+  attr_writer sig_root_dir: String
+
+  def initialize: (?name: Symbol) ?{ () -> untyped } -> void
+  def define_generate_task: () -> void
+  private def parse_options: (argv: Array[String]) -> { force: bool }
+end
diff --git a/sig/type_generator.rbs b/sig/type_generator.rbs
new file mode 100644
index 0000000..205d3ba
--- /dev/null
+++ b/sig/type_generator.rbs
@@ -0,0 +1,12 @@
+class OpenapiRailsTypedParameters::TypeGenerator
+  @config: OpenapiRailsTypedParameters::Configuration
+  @validator: __todo__
+  private attr_accessor config: OpenapiRailsTypedParameters::Configuration
+  private attr_accessor validator: __todo__
+  private def initialize: () -> void
+  def generate_rbs: () -> String
+  def operation_to_type_name: (operation: __todo__) -> String
+  def generate_parameter_definitions: () -> String
+  def generate_controller_definitions: () -> String
+  def format: (String rbs) -> String
+end
diff --git a/sig/typed_parameters.rbs b/sig/typed_parameters.rbs
new file mode 100644
index 0000000..3d6ebc4
--- /dev/null
+++ b/sig/typed_parameters.rbs
@@ -0,0 +1,17 @@
+
+
+class OpenapiRailsTypedParameters::TypedParameters
+  type parameter_value = String | Integer | Symbol | bool
+  type parameters = Hash[Symbol, parameter_value?]
+
+  @request: __todo__
+  attr_reader request: __todo__
+  private def initialize: (request: __todo__) -> void
+  def path_params: () -> parameters
+  def query_params: () -> parameters
+  def valid?: () -> bool
+  def to_h: () -> { path_params: parameters, query_params: parameters, body: String?, valid: bool }
+  def validate!: () -> void
+  def body: () -> String
+  def validate: () -> __todo__
+end

From 3c4ec53e0f22ad6a5657d392f1f2829d8a167dcb Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Mon, 29 Jan 2024 03:53:19 +0900
Subject: [PATCH 14/16] rbs prototype using orthoses

---
 Gemfile      |  4 ++++
 Gemfile.lock |  3 +++
 Rakefile     | 44 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)

diff --git a/Gemfile b/Gemfile
index 316b434..3cacbd5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -17,3 +17,7 @@ group :lint do
   gem 'rubocop'
   gem 'steep'
 end
+
+group :rbs do
+  gem 'orthoses'
+end
diff --git a/Gemfile.lock b/Gemfile.lock
index 9e06cb2..b68e54e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -97,6 +97,8 @@ GEM
     openapi_parameters (0.3.2)
       rack (>= 2.2)
       zeitwerk (~> 2.6)
+    orthoses (1.13.0)
+      rbs (~> 3.0)
     parallel (1.24.0)
     parser (3.3.0.0)
       ast (~> 2.4.1)
@@ -214,6 +216,7 @@ PLATFORMS
 DEPENDENCIES
   debug
   openapi_rails_typed_parameters!
+  orthoses
   rake
   rspec
   rspec-rails
diff --git a/Rakefile b/Rakefile
index 4964751..92a88c0 100644
--- a/Rakefile
+++ b/Rakefile
@@ -10,3 +10,47 @@ require 'rubocop/rake_task'
 RuboCop::RakeTask.new
 
 task default: %i[spec rubocop]
+
+desc 'Generate RBS'
+task :generate_rbs do
+  require 'active_support/testing/stream'
+  require 'orthoses'
+  require_relative 'lib/openapi_rails_typed_parameters'
+
+  namespace = OpenapiRailsTypedParameters.to_s
+
+  out = Pathname(__FILE__).dirname / 'sig/generated'
+
+  begin
+    out.rmtree
+  rescue StandardError
+    nil
+  end
+
+  Orthoses.logger.level = :warn
+  Orthoses::Builder.new do
+    use Orthoses::CreateFileByName,
+        to: 'sig/generated',
+        rmtree: true,
+        header: '# Generated code'
+    use Orthoses::Filter do |name, _content|
+      name.start_with?(namespace)
+    end
+    use Orthoses::Mixin
+    use Orthoses::Constant
+    use Orthoses::Trace,
+        patterns: [namespace, "#{namespace}::*"]
+    use Orthoses::RBSPrototypeRB,
+        paths: Dir.glob('lib/**/*.rb')
+    run lambda {
+      _ = OpenapiRailsTypedParameters::VERSION
+      Class.new.extend(ActiveSupport::Testing::Stream).instance_exec do
+        silence_stream($stdout) do
+          require 'rspec'
+          spec_files = Dir.glob('spec/**/*_spec.rb')
+          RSpec::Core::Runner.run(spec_files)
+        end
+      end
+    }
+  end.call
+end

From 525ed59c507a36936bb55a221e70ae2f5914f539 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Mon, 29 Jan 2024 03:53:27 +0900
Subject: [PATCH 15/16] binstubs

---
 bin/rdbg  | 27 +++++++++++++++++++++++++++
 bin/rspec | 27 +++++++++++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100755 bin/rdbg
 create mode 100755 bin/rspec

diff --git a/bin/rdbg b/bin/rdbg
new file mode 100755
index 0000000..5e3b279
--- /dev/null
+++ b/bin/rdbg
@@ -0,0 +1,27 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rdbg' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+bundle_binstub = File.expand_path("bundle", __dir__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300).include?("This file was generated by Bundler")
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("debug", "rdbg")
diff --git a/bin/rspec b/bin/rspec
new file mode 100755
index 0000000..cb53ebe
--- /dev/null
+++ b/bin/rspec
@@ -0,0 +1,27 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'rspec' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+bundle_binstub = File.expand_path("bundle", __dir__)
+
+if File.file?(bundle_binstub)
+  if File.read(bundle_binstub, 300).include?("This file was generated by Bundler")
+    load(bundle_binstub)
+  else
+    abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
+Replace `bin/bundle` by running `bundle binstubs bundler --force`, then run this command again.")
+  end
+end
+
+require "rubygems"
+require "bundler/setup"
+
+load Gem.bin_path("rspec-core", "rspec")

From 2b21cdbc84b23197b18e5394e5b49b4879604aa6 Mon Sep 17 00:00:00 2001
From: supermomonga <hi@supermomonga.com>
Date: Mon, 29 Jan 2024 04:32:54 +0900
Subject: [PATCH 16/16] readme

---
 README.md | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 79 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index dbc7d32..e333233 100644
--- a/README.md
+++ b/README.md
@@ -36,8 +36,62 @@ Add `openapi_rails_typed_parameters` to your Gemfile.
 gem 'openapi_rails_typed_parameters'
 ```
 
+Then, install rake task by generator.
+
+```sh
+bin/rails g openapi_rails_typed_parameters:install
+```
+
+## Usage
+
+Run `openapi_rails_typed_parameters:generate` rake task.
+
+```sh
+bin/rails openapi_rails_typed_parameters:generate
+```
+
+If you update your OpenAPI definition, then generate again with `--force` option. It overwrites RBSs.
+
+```sh
+bin/rails openapi_rails_typed_parameters:generate --force
+```
+
 ## Usage
 
+Add `using OpenapiRailsTypedParameters` to your controller class. You can access statically typed parameters via `typed_params` method.
+
+```rb
+class UsersController < ApplicationController
+  using OpenapiRailsTypedParameters
+
+  def index
+    # BEFORE: Default Rails code.
+    params.permit(:role)
+    role_string = params[:role]
+    role =
+      if role_string.present?
+        if ['admin', 'maintainer', 'member'].include?(role_string)
+          role_string.to_sym
+        else
+          raise 'Unknown `role` passed. available values are: [admin, maintainer, member].'
+        end
+      else
+        :member # fallback to default
+      end
+
+    # AFTER: Typed parameters way.
+    # role is validated, and it's type coerced.
+    role = typed_params.query_params.role # :admin, :maintainer or :member
+
+    @users = User.where(role:)
+    render :index
+  end
+end
+
+```
+
+## RBS generation, static typing
+
 Please add an initializer to your Rails application and specify the path to the OpenAPI schema file.
 
 e.g.) `config/initializers/openapi.rb`
@@ -50,7 +104,29 @@ OpenapiRailsTypedParameters.configure do |config|
 end
 ```
 
-Then, add `using OpenapiRailsTypedParameters` to your controller class. You can access statically typed parameters via `typed_parameters` method.
+If you want to customize generator behavior, edit `lib/tasks/openapi_rails_typed_parameters.rake`.
+
+Then, you can use statically typed parameters. Please use `typed_params_for(:action_name)` instead of `typed_params`.
+
+Enjoy statically typed params with your favorite LSP server.
+
+```rb
+class UsersController < ApplicationController
+  using OpenapiRailsTypedParameters
+
+  def index
+    # BEFORE: RBS not injected.
+    _ = typed_params
+
+    # AFTER: RBS injected.
+    _ = typed_params_for(:index)
+
+    role = typed_params_for(:index).query_params.role
+    @users = User.where(role:)
+    render :index
+  end
+end
+```
 
 ## Example
 
@@ -70,7 +146,8 @@ paths:
           required: true
           schema:
             type: string
-            enum: [ admin, maintainer ]
+            enum: [ admin, maintainer, member ]
+            default: member
         - name: minimum
           in: query
           required: false