Enable defer_rails_initialization config by environment variable only

.github/workflows/performance_tests.yml

@@ -6,6 +6,7 @@ on:
       - main
   schedule:
     - cron:  '0 9 * * 0'
+  workflow_dispatch:
 
 jobs:
   check_branch_changes:

lib/new_relic/agent/configuration/default_source.rb

@@ -1865,16 +1865,6 @@ def self.enforce_fallback(allowed_values: nil, fallback: nil)
           :allowed_from_server => false,
           :description => 'Specify a custom host name for [display in the New Relic UI](/docs/apm/new-relic-apm/maintenance/add-rename-remove-hosts#display_name).'
         },
-        # Rails
-        :'defer_rails_initialization' => {
-          :default => false,
-          :public => true,
-          :type => Boolean,
-          :allowed_from_server => false,
-          :description => 'This configuration option is currently unreachable. Please do not use. ' \
-            'If `true`, when the agent is in an application using Ruby on Rails, it will start after ' \
-            'config/initializers have run.'
-        },
         # Rake
         :'rake.tasks' => {
           :default => [],

lib/new_relic/control/instance_methods.rb

@@ -65,7 +65,7 @@ def init_plugin(options = {})
         # An artifact of earlier implementation, we put both #add_method_tracer and #trace_execution
         # methods in the module methods.
         # Rails applications load the next two lines before any other initializers are run
-        unless defined?(Rails::VERSION) && NewRelic::Agent.config[:defer_rails_initialization]
+        unless defined?(Rails::VERSION)
           Module.send(:include, NewRelic::Agent::MethodTracer::ClassMethods)
           Module.send(:include, NewRelic::Agent::MethodTracer)
         end

lib/newrelic_rpm.rb

@@ -20,19 +20,13 @@
 if defined?(Rails::VERSION)
   module NewRelic
     class Railtie < Rails::Railtie
-      if NewRelic::Agent.config[:defer_rails_initialization]
-        initializer "newrelic_rpm.include_method_tracers", before: :load_config_initializers do |app|
-          Module.send(:include, NewRelic::Agent::MethodTracer::ClassMethods)
-          Module.send(:include, NewRelic::Agent::MethodTracer)
-        end
+      initializer "newrelic_rpm.include_method_tracers", before: :load_config_initializers do |app|
+        Module.send(:include, NewRelic::Agent::MethodTracer::ClassMethods)
+        Module.send(:include, NewRelic::Agent::MethodTracer)
+      end
 
-        initializer "newrelic_rpm.start_plugin", after: :load_config_initializers do |app|
-          NewRelic::Control.instance.init_plugin(config: app.config)
-        end
-      else
-        initializer "newrelic_rpm.start_plugin", before: :load_config_initializers do |app|
-          NewRelic::Control.instance.init_plugin(config: app.config)
-        end
+      initializer "newrelic_rpm.start_plugin", after: :load_config_initializers do |app|
+        NewRelic::Control.instance.init_plugin(config: app.config)
       end
     end
   end

newrelic.yml

@@ -162,10 +162,6 @@ common: &default_settings
   # or  port_path_or_id parameters to transaction or slow SQL traces.
   # datastore_tracer.instance_reporting.enabled: true
 
-  # If true, when the agent is in an application using Ruby on Rails, it will start after
-  # config/initializers have run.
-  # defer_rails_initialization: false
-
   # If true, disables Action Cable instrumentation.
   # disable_action_cable_instrumentation: false
 

test/environments/rails60/config/initializers/test.rb

@@ -16,5 +16,6 @@ def sniff
 
   add_method_tracer :sniff
 end
-
+puts Rails.application.config.active_record.timestamped_migrations
 Rails.application.config.active_record.timestamped_migrations = false
+puts Rails.application.config.active_record.timestamped_migrations

test/new_relic/newrelic_rpm_test.rb

@@ -5,37 +5,22 @@
 require_relative '../test_helper'
 
 class NewRelicRpmTest < Minitest::Test
+  RAILS_32_SKIP_MESSAGE = 'MySQL error for Rails 3.2 when we add an initializer to config/initializers'
   # This test examines the behavior of an initializer when the agent is started in a Rails context
   # The initializer used for these tests is defined in test/environments/*/config/inititalizers/test.rb
 
   # We have documentation recommending customers call add_method_tracer
   # in their initializers, let's make sure this works
-  def test_add_method_tracer_in_initializer_gets_traced_when_agent_initialized_before_config_initializers
-    skip unless defined?(Rails::VERSION)
-    skip 'MySQL error for Rails 3.2' if Rails::VERSION::MAJOR == 3
-
-    with_config(defer_rails_initialization: false) do
-      assert Bloodhound.newrelic_method_exists?('sniff'),
-        'Bloodhound#sniff not found by' \
-        'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.newrelic_method_exists?'
-      assert Bloodhound.method_traced?('sniff'),
-        'Bloodhound#sniff not found by' \
-        'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.method_traced?'
-    end
-  end
-
   def test_add_method_tracer_in_initializer_gets_traced_when_agent_initialized_after_config_initializers
     skip unless defined?(Rails::VERSION)
-    skip 'MySQL error for Rails 3.2 if we define an initializer in config/initializers' if Rails::VERSION::MAJOR == 3
-
-    with_config(defer_rails_initialization: true) do
-      assert Bloodhound.newrelic_method_exists?('sniff'),
-        'Bloodhound#sniff not found by' \
-        'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.newrelic_method_exists?'
-      assert Bloodhound.method_traced?('sniff'),
-        'Bloodhound#sniff not found by' \
-        'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.method_traced?'
-    end
+    skip RAILS_32_SKIP_MESSAGE if Rails::VERSION::MAJOR == 3
+
+    assert Bloodhound.newrelic_method_exists?('sniff'),
+      'Bloodhound#sniff not found by' \
+      'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.newrelic_method_exists?'
+    assert Bloodhound.method_traced?('sniff'),
+      'Bloodhound#sniff not found by' \
+      'NewRelic::Agent::MethodTracer::ClassMethods::AddMethodTracer.method_traced?'
   end
 
   # All supported Rails versions have the default value for
@@ -44,42 +29,19 @@ def test_add_method_tracer_in_initializer_gets_traced_when_agent_initialized_aft
 
   def test_active_record_initializer_config_change_saved_when_agent_initialized_after_config_initializers
     skip unless defined?(Rails::VERSION)
-    # TODO: This test passes in a Rails console in a playground app and in the customer's environment
-    # but fails in this unit test context
-    skip if Gem::Version.new(NewRelic::VERSION::STRING) >= Gem::Version.new('8.13.0')
-    skip 'MySQL error for Rails 3.2' if Rails::VERSION::MAJOR == 3
-
-    with_config(defer_rails_initialization: true) do
-      # Verify the configuration value was set to the initializer value
-      refute Rails.application.config.active_record.timestamped_migrations,
-        "Rails.application.config.active_record.timestamped_migrations equals true, expected false"
-
-      # Verify the configuration value was applied to the ActiveRecord class variable
-      if Gem::Version.new(Rails::VERSION::STRING) >= Gem::Version.new('7.1')
-        refute ActiveRecord.timestamped_migrations, "ActiveRecord.timestamped_migrations equals true, expected false"
-      else
-        refute ActiveRecord::Base.timestamped_migrations,
-          "ActiveRecord::Base.timestamped_migrations equals true, expected false"
-      end
-    end
-  end
-
-  def test_active_record_initializer_config_change_not_saved_when_agent_initialized_before_config_initializers
-    skip unless defined?(Rails::VERSION)
-    skip 'MySQL error for Rails 3.2' if Rails::VERSION::MAJOR == 3
-
-    with_config(defer_rails_initialization: false) do
-      # Verify the configuration value was set to the initializer value
-      refute Rails.application.config.active_record.timestamped_migrations,
-        "Rails.application.config.active_record.timestamped_migrations equals true, expected false"
-
-      # Rails.application.config value should not be applied (this is the state of the original bug)
-      if Gem::Version.new(Rails::VERSION::STRING) >= Gem::Version.new('7.1')
-        assert ActiveRecord.timestamped_migrations, "ActiveRecord.timestamped_migrations equals false, expected true"
-      else
-        assert ActiveRecord::Base.timestamped_migrations,
-          "ActiveRecord::Base.timestamped_migrations equals false, expected true"
-      end
+    skip RAILS_32_SKIP_MESSAGE if Rails::VERSION::MAJOR == 3
+    # skip "Test passes in a Rails console on a playground app and in the customer's environment, but fails here"
+
+    # Verify the configuration value was set to the initializer value
+    refute Rails.application.config.active_record.timestamped_migrations,
+      "Rails.application.config.active_record.timestamped_migrations equals true, expected false"
+
+    # Verify the configuration value was applied to the ActiveRecord class variable
+    if Gem::Version.new(Rails::VERSION::STRING) >= Gem::Version.new('7.1')
+      refute ActiveRecord.timestamped_migrations, "ActiveRecord.timestamped_migrations equals true, expected false"
+    else
+      refute ActiveRecord::Base.timestamped_migrations,
+        "ActiveRecord::Base.timestamped_migrations equals true, expected false"
     end
   end
 end