Changed: Rails to patch Base, API instead of Metal.

lib/ddtrace/contrib/rails/action_controller.rb

@@ -8,15 +8,6 @@ module Contrib
     module Rails
       # Code used to create and handle 'rails.action_controller' spans.
       module ActionController
-        include Datadog::Patcher
-
-        def self.instrument
-          # patch Rails core components
-          do_once(:instrument) do
-            Datadog::RailsActionPatcher.patch_action_controller
-          end
-        end
-
         def self.start_processing(payload)
           # trace the execution
           tracer = Datadog.configuration[:rails][:tracer]

lib/ddtrace/contrib/rails/action_controller_patch.rb

@@ -4,6 +4,8 @@ module Rails
       # Instrument ActiveController processing
       module ActionControllerPatch
         def self.included(base)
+          return if base.ancestors.include?(ProcessActionPatch)
+
           if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.0.0')
             base.send(:prepend, ProcessActionPatch)
           else

lib/ddtrace/contrib/rails/active_support.rb

@@ -6,15 +6,6 @@ module Contrib
     module Rails
       # Code used to create and handle 'rails.cache' spans.
       module ActiveSupport
-        include Datadog::Patcher
-
-        def self.instrument
-          do_once(:instrument) do
-            # patch Rails core components
-            Datadog::RailsCachePatcher.patch_cache_store
-          end
-        end
-
         def self.start_trace_cache(payload)
           tracer = Datadog.configuration[:rails][:tracer]
 

lib/ddtrace/contrib/rails/core_extensions.rb

@@ -169,22 +169,6 @@ def with_datadog_span(span)
   module RailsActionPatcher
     include Datadog::Patcher
 
-    # Patch for ActionController::Metal
-    module MetalPatch
-      # For any Controller class that inherits from ActionController::Metal,
-      # make sure to include the tracing patch. We do this instead of Metal.include(Patch)
-      # because Base and API compose modules that would take precedence over the tracing patch.
-      # By adding it onto the inheriting class, we can make sure it has a higher precedence.
-      def inherited(base)
-        super
-
-        # Make sure not to include the patch twice, to avoid double measurements on controllers.
-        unless base.ancestors.include?(Datadog::Contrib::Rails::ActionControllerPatch)
-          base.send(:include, Datadog::Contrib::Rails::ActionControllerPatch)
-        end
-      end
-    end
-
     module_function
 
     def patch_action_controller
@@ -197,7 +181,13 @@ def patch_process_action
       do_once(:patch_process_action) do
         require 'ddtrace/contrib/rails/action_controller_patch'
 
-        ::ActionController::Metal.extend(MetalPatch)
+        if defined?(::ActionController::Base)
+          ::ActionController::Base.send(:include, Datadog::Contrib::Rails::ActionControllerPatch)
+        end
+
+        if defined?(::ActionController::API)
+          ::ActionController::API.send(:include, Datadog::Contrib::Rails::ActionControllerPatch)
+        end
       end
     end
   end

lib/ddtrace/contrib/rails/framework.rb

@@ -8,7 +8,6 @@
 require 'ddtrace/contrib/rails/ext'
 require 'ddtrace/contrib/rails/core_extensions'
 require 'ddtrace/contrib/rails/action_controller'
-require 'ddtrace/contrib/rails/action_view'
 require 'ddtrace/contrib/rails/active_support'
 require 'ddtrace/contrib/rails/utils'
 

lib/ddtrace/contrib/rails/patcher.rb

@@ -76,9 +76,9 @@ def setup_tracer
 
         # Add instrumentation to Rails components
         def instrument_rails
-          Datadog::Contrib::Rails::ActionController.instrument
-          Datadog::Contrib::Rails::ActionView.instrument
-          Datadog::Contrib::Rails::ActiveSupport.instrument
+          Datadog::RailsActionPatcher.patch_action_controller
+          Datadog::RailsRendererPatcher.patch_renderer
+          Datadog::RailsCachePatcher.patch_cache_store
         end
       end
     end

spec/ddtrace/contrib/rails/action_controller_spec.rb

@@ -1,11 +1,10 @@
 require 'ddtrace/contrib/rails/rails_helper'
 
 RSpec.describe 'ActionController tracing' do
-  let(:tracer) { ::Datadog::Tracer.new(writer: FauxWriter.new) }
+  let(:tracer) { get_test_tracer }
   let(:rails_options) { { tracer: tracer } }
 
   before(:each) do
-    Datadog::RailsActionPatcher.patch_action_controller
     Datadog.configure do |c|
       c.use :rails, rails_options
     end

spec/ddtrace/contrib/rails/middleware_spec.rb

@@ -32,7 +32,6 @@ def all_spans
   end
 
   before(:each) do
-    Datadog::RailsActionPatcher.patch_action_controller
     Datadog.configure do |c|
       c.use :rack, rack_options if use_rack
       c.use :rails, rails_options if use_rails

spec/ddtrace/contrib/rails/railtie_spec.rb

@@ -9,17 +9,6 @@
 
   let(:tracer) { ::Datadog::Tracer.new(writer: FauxWriter.new) }
 
-  let(:routes) { { '/' => 'test#index' } }
-  let(:controllers) { [controller] }
-
-  let(:controller) do
-    stub_const('TestController', Class.new(ActionController::Base) do
-      def index
-        head :ok
-      end
-    end)
-  end
-
   RSpec::Matchers.define :have_kind_of_middleware do |expected|
     match do |actual|
       found = 0