Use :unprocessable_content for scaffolds with Rack 3.1 or higher

Author: taketo1113

lib/generators/rails/scaffold_controller_generator.rb

@@ -15,6 +15,10 @@ class ScaffoldControllerGenerator
         def permitted_params
           attributes_names.map { |name| ":#{name}" }.join(', ')
         end unless private_method_defined? :permitted_params
+
+        def status_unprocessable_content
+          ::Rack::Utils::SYMBOL_TO_STATUS_CODE.key(422) rescue :unprocessable_content
+        end
     end
   end
 end

lib/generators/rails/templates/api_controller.rb

@@ -25,7 +25,7 @@ def create
     if @<%= orm_instance.save %>
       render :show, status: :created, location: <%= "@#{singular_table_name}" %>
     else
-      render json: <%= "@#{orm_instance.errors}" %>, status: :unprocessable_entity
+      render json: <%= "@#{orm_instance.errors}" %>, status: :<%= status_unprocessable_content.to_s %>
     end
   end
 
@@ -35,7 +35,7 @@ def update
     if @<%= orm_instance.update("#{singular_table_name}_params") %>
       render :show, status: :ok, location: <%= "@#{singular_table_name}" %>
     else
-      render json: <%= "@#{orm_instance.errors}" %>, status: :unprocessable_entity
+      render json: <%= "@#{orm_instance.errors}" %>, status: :<%= status_unprocessable_content.to_s %>
     end
   end
 

lib/generators/rails/templates/controller.rb

@@ -33,8 +33,8 @@ def create
         format.html { redirect_to <%= redirect_resource_name %>, notice: <%= %("#{human_name} was successfully created.") %> }
         format.json { render :show, status: :created, location: <%= "@#{singular_table_name}" %> }
       else
-        format.html { render :new, status: :unprocessable_entity }
-        format.json { render json: <%= "@#{orm_instance.errors}" %>, status: :unprocessable_entity }
+        format.html { render :new, status: :<%= status_unprocessable_content.to_s %> }
+        format.json { render json: <%= "@#{orm_instance.errors}" %>, status: :<%= status_unprocessable_content.to_s %> }
       end
     end
   end
@@ -46,8 +46,8 @@ def update
         format.html { redirect_to <%= redirect_resource_name %>, notice: <%= %("#{human_name} was successfully updated.") %>, status: :see_other }
         format.json { render :show, status: :ok, location: <%= "@#{singular_table_name}" %> }
       else
-        format.html { render :edit, status: :unprocessable_entity }
-        format.json { render json: <%= "@#{orm_instance.errors}" %>, status: :unprocessable_entity }
+        format.html { render :edit, status: :<%= status_unprocessable_content.to_s %> }
+        format.json { render json: <%= "@#{orm_instance.errors}" %>, status: :<%= status_unprocessable_content.to_s %> }
       end
     end
   end

test/scaffold_api_controller_generator_test.rb

@@ -24,12 +24,20 @@ class ScaffoldApiControllerGeneratorTest < Rails::Generators::TestCase
         assert_match %r{@post = Post\.new\(post_params\)}, m
         assert_match %r{@post\.save}, m
         assert_match %r{render :show, status: :created, location: @post}, m
-        assert_match %r{render json: @post\.errors, status: :unprocessable_entity}, m
+        if Gem::Version.new(Rack::RELEASE) < Gem::Version.new("3.1")
+          assert_match %r{render json: @post\.errors, status: :unprocessable_entity}, m
+        else
+          assert_match %r{render json: @post\.errors, status: :unprocessable_content}, m
+        end
       end
 
       assert_instance_method :update, content do |m|
         assert_match %r{render :show, status: :ok, location: @post}, m
-        assert_match %r{render json: @post.errors, status: :unprocessable_entity}, m
+        if Gem::Version.new(Rack::RELEASE) < Gem::Version.new("3.1")
+          assert_match %r{render json: @post.errors, status: :unprocessable_entity}, m
+        else
+          assert_match %r{render json: @post.errors, status: :unprocessable_content}, m
+        end
       end
 
       assert_instance_method :destroy, content do |m|

test/scaffold_controller_generator_test.rb

@@ -33,15 +33,25 @@ class ScaffoldControllerGeneratorTest < Rails::Generators::TestCase
         assert_match %r{@post\.save}, m
         assert_match %r{format\.html \{ redirect_to @post, notice: "Post was successfully created\." \}}, m
         assert_match %r{format\.json \{ render :show, status: :created, location: @post \}}, m
-        assert_match %r{format\.html \{ render :new, status: :unprocessable_entity \}}, m
-        assert_match %r{format\.json \{ render json: @post\.errors, status: :unprocessable_entity \}}, m
+        if Gem::Version.new(Rack::RELEASE) < Gem::Version.new("3.1")
+          assert_match %r{format\.html \{ render :new, status: :unprocessable_entity \}}, m
+          assert_match %r{format\.json \{ render json: @post\.errors, status: :unprocessable_entity \}}, m
+        else
+          assert_match %r{format\.html \{ render :new, status: :unprocessable_content \}}, m
+          assert_match %r{format\.json \{ render json: @post\.errors, status: :unprocessable_content \}}, m
+        end
       end
 
       assert_instance_method :update, content do |m|
         assert_match %r{format\.html \{ redirect_to @post, notice: "Post was successfully updated\.", status: :see_other \}}, m
         assert_match %r{format\.json \{ render :show, status: :ok, location: @post \}}, m
-        assert_match %r{format\.html \{ render :edit, status: :unprocessable_entity \}}, m
-        assert_match %r{format\.json \{ render json: @post.errors, status: :unprocessable_entity \}}, m
+        if Gem::Version.new(Rack::RELEASE) < Gem::Version.new("3.1")
+          assert_match %r{format\.html \{ render :edit, status: :unprocessable_entity \}}, m
+          assert_match %r{format\.json \{ render json: @post.errors, status: :unprocessable_entity \}}, m
+        else
+          assert_match %r{format\.html \{ render :edit, status: :unprocessable_content \}}, m
+          assert_match %r{format\.json \{ render json: @post.errors, status: :unprocessable_content \}}, m
+        end
       end
 
       assert_instance_method :destroy, content do |m|