[rails] prevent patching and instrumenting the Rails framework if use…

…rs disable that
DataDog · Jan 13, 2017 · 3e83010 · 3e83010
1 parent 909c5da
commit 3e83010
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Showing 2 changed files with 21 additions and 13 deletions.
diff --git a/lib/ddtrace.rb b/lib/ddtrace.rb
@@ -28,25 +28,27 @@ def self.tracer
 # Datadog auto instrumentation for frameworks
 if defined?(Rails::VERSION)
   if Rails::VERSION::MAJOR.to_i >= 3
-    begin
-      # We include 'redis-rails' here if it's available, doing it later
-      # (typically in initialize callback) does not work, it does not
-      # get loaded in the right context.
-      require 'redis-rails'
-      Datadog::Tracer.log.info("'redis-rails' module found, datadog redis integration is available")
-    rescue LoadError
-      Datadog::Tracer.log.info("no 'redis-rails' module found, datadog redis integration is not available")
-    end
     require 'ddtrace/contrib/rails/framework'
 
-    Datadog::Monkey.patch_module(:redis) # does nothing if redis is not loaded
-    Datadog::RailsPatcher.patch_renderer()
-    Datadog::RailsPatcher.patch_cache_store()
-
     module Datadog
       # Run the auto instrumentation directly after the initialization of the application and
       # after the application initializers in config/initializers are run
       class Railtie < Rails::Railtie
+        config.before_configuration do |app|
+          begin
+            # We include 'redis-rails' here if it's available, doing it later
+            # (typically in initialize callback) does not work, it does not
+            # get loaded in the right context.
+            require 'redis-rails'
+            Datadog::Tracer.log.info("'redis-rails' module found, datadog redis integration is available")
+          rescue LoadError
+            Datadog::Tracer.log.info("no 'redis-rails' module found, datadog redis integration is not available")
+          end
+
+          Datadog::Monkey.patch_module(:redis)
+        end
+
+        # we do actions
         config.after_initialize do |app|
           Datadog::Contrib::Rails::Framework.configure(config: app.config)
           Datadog::Contrib::Rails::Framework.auto_instrument()

diff --git a/lib/ddtrace/contrib/rails/framework.rb b/lib/ddtrace/contrib/rails/framework.rb
@@ -94,6 +94,12 @@ def self.auto_instrument_redis
         def self.auto_instrument
           return unless ::Rails.configuration.datadog_trace[:auto_instrument]
           Datadog::Tracer.log.info('Detected Rails >= 3.x. Enabling auto-instrumentation for core components.')
+
+          # patch Rails core components
+          Datadog::RailsPatcher.patch_renderer()
+          Datadog::RailsPatcher.patch_cache_store()
+
+          # instrumenting Rails framework
           Datadog::Contrib::Rails::ActionController.instrument()
           Datadog::Contrib::Rails::ActionView.instrument()
           Datadog::Contrib::Rails::ActiveRecord.instrument() if defined?(::ActiveRecord)