5 files changed, 37 insertions, 2 deletions
diff --git a/railties/CHANGELOG.md b/railties/CHANGELOG.md
index f94b67a0ac..65dccbb3be 100644
--- a/railties/CHANGELOG.md
+++ b/railties/CHANGELOG.md
@@ -1,3 +1,9 @@
+*   Add JSON support to rails properties route (`/rails/info/properties`).
+
+    Now, `Rails::Info` properties may be accessed in JSON format at `/rails/info/properties.json`.
+
+    *Yoshiyuki Hirano*
+
 *   Use Ids instead of memory addresses when displaying references in scaffold views.
 
     Fixes #29200.
diff --git a/railties/lib/rails/info.rb b/railties/lib/rails/info.rb
index 3df36efc4c..b8173c8d11 100644
--- a/railties/lib/rails/info.rb
+++ b/railties/lib/rails/info.rb
@@ -54,6 +54,10 @@ module Rails
           table << "</table>"
         end
       end
+
+      def to_json
+        Hash[properties].to_json
+      end
     end
 
     # The Rails version.
diff --git a/railties/lib/rails/info_controller.rb b/railties/lib/rails/info_controller.rb
index b4f4a5922a..50fe176946 100644
--- a/railties/lib/rails/info_controller.rb
+++ b/railties/lib/rails/info_controller.rb
@@ -14,8 +14,16 @@ class Rails::InfoController < Rails::ApplicationController # :nodoc:
   end
 
   def properties
-    @info = Rails::Info.to_html
-    @page_title = "Properties"
+    respond_to do |format|
+      format.html do
+        @info = Rails::Info.to_html
+        @page_title = "Properties"
+      end
+
+      format.json do
+        render json: Rails::Info.to_json
+      end
+    end
   end
 
   def routes
diff --git a/railties/test/rails_info_controller_test.rb b/railties/test/rails_info_controller_test.rb
index 878a238f8d..6ab68f8333 100644
--- a/railties/test/rails_info_controller_test.rb
+++ b/railties/test/rails_info_controller_test.rb
@@ -50,6 +50,11 @@ class InfoControllerTest < ActionController::TestCase
     assert_select "table"
   end
 
+  test "info controller renders json with properties" do
+    get :properties, format: :json
+    assert_equal Rails::Info.to_json, response.body
+  end
+
   test "info controller renders with routes" do
     get :routes
     assert_response :success
diff --git a/railties/test/rails_info_test.rb b/railties/test/rails_info_test.rb
index 50522c1be6..d167a86e56 100644
--- a/railties/test/rails_info_test.rb
+++ b/railties/test/rails_info_test.rb
@@ -43,6 +43,18 @@ class InfoTest < ActiveSupport::TestCase
     end
   end
 
+  def test_json_includes_middleware
+    Rails::Info.module_eval do
+      property "Middleware", ["Rack::Lock", "Rack::Static"]
+    end
+
+    hash = JSON.parse(Rails::Info.to_json)
+    assert_includes hash.keys, "Middleware"
+    properties.value_for("Middleware").each do |value|
+      assert_includes hash["Middleware"], value
+    end
+  end
+
   private
     def properties
       Rails::Info.properties