add a code reload interceptor for rails

CHANGELOG.md

@@ -3,6 +3,7 @@ Changelog for the gruf gem. This includes internal history before the gem was ma
 ### Pending release
 
 * [#190] Remove unsued `e2mmap` and `thwait` gems from `runtime_dependency`.
+* [#194] Add interceptor to reload Rails app code accross requests
 
 ### 2.19.0
 

lib/gruf/configuration.rb

@@ -189,6 +189,9 @@ def reset
       self.use_default_interceptors = ::ENV.fetch('GRUF_USE_DEFAULT_INTERCEPTORS', 1).to_i.positive?
 
       if use_default_interceptors
+        if defined?(::Rails)
+          interceptors.use(::Gruf::Interceptors::Rails::Reloader, reloader: Rails.application.reloader)
+        end
         interceptors.use(::Gruf::Interceptors::ActiveRecord::ConnectionReset)
         interceptors.use(::Gruf::Interceptors::Instrumentation::OutputMetadataTimer)
       end

lib/gruf/interceptors/rails/reloader.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+# Copyright (c) 2017-present, BigCommerce Pty. Ltd. All rights reserved
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+# documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit
+# persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
+# Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+# COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+module Gruf
+  module Interceptors
+    module Rails
+      ##
+      # Triggers rails code reloading between requests
+      #
+      class Reloader < ::Gruf::Interceptors::ServerInterceptor
+        def call(&block)
+          options[:reloader].wrap(&block)
+        end
+      end
+    end
+  end
+end