Add guards in component for Ruby and libdatadog

Author: Strech

.cursor/rules/architecture.mdc

@@ -5,14 +5,16 @@ alwaysApply: false
 ---
 # Architecture and Design
 
-This library provides tools to get visibility into the performance and security of Ruby applications. This includes distributed tracing, profiling, app & api protection, dynamic instrumentation, metrics emission, etc.
+This library provides tools to get visibility into the performance and security of Ruby applications.
+This includes distributed tracing, profiling, app & api protection, dynamic instrumentation, metrics emission, open feature, etc.
 
 ## Project Structure
 
 - @lib/datadog/appsec - app & api protection implementation (formely known as appsec)
 - @lib/datadog/appsec/contrib - app & api protection integrations with third-party libraries
 - @lib/datadog/core - glue and shared code
 - @lib/datadog/di - dynamic instrumentation
+- @lib/datadog/open_feature - an implementation of OpenFeature Provider https://openfeature.dev/docs/reference/sdks/server/ruby
 - @lib/datadog/profiling - profiling
 - @lib/datadog/tracing - distributed tracing
 - @lib/datadog/tracing/contrib - distributed tracing integrations with third-party libraries

lib/datadog/open_feature/component.rb

@@ -18,9 +18,26 @@ def self.build(settings, agent_settings, logger:, telemetry:)
 
         unless settings.respond_to?(:remote) && settings.remote.enabled
           message = 'OpenFeature could not be enabled as Remote Configuration is currently disabled. ' \
-            'To enable Remote Configuration, see https://docs.datadoghq.com/agent/remote_config'
+            'To enable Remote Configuration, see https://docs.datadoghq.com/remote_configuration/.'
+
+          logger.warn(message)
+          return
+        end
+
+        if RUBY_ENGINE != 'ruby'
+          message = 'OpenFeature could not be enabled as MRI is required, ' \
+            "but running on #{RUBY_ENGINE.inspect}"
+
           logger.warn(message)
+          return
+        end
 
+        if (libdatadog_api_failure = Core::LIBDATADOG_API_FAILURE)
+          message = 'OpenFeature could not be enabled as `libdatadog` is not loaded: ' \
+            "#{libdatadog_api_failure.inspect}. For help solving this issue, " \
+            'please contact Datadog support at https://docs.datadoghq.com/help/.'
+
+          logger.warn(message)
           return
         end
 

spec/datadog/open_feature/component_spec.rb

@@ -27,21 +27,44 @@
       before { settings.open_feature.enabled = true }
 
       context 'when remote configuration is enabled' do
-        before { settings.remote.enabled = true }
+        before do
+          stub_const('Datadog::Core::LIBDATADOG_API_FAILURE', nil)
+          settings.remote.enabled = true
+        end
 
         it 'returns configured component instance' do
           expect(component).to be_a(described_class)
           expect(component.engine).to be_a(Datadog::OpenFeature::EvaluationEngine)
+
           expect(Datadog::OpenFeature::Exposures::Reporter).to have_received(:new)
         end
+
+        context 'when libdatadog is unavailable' do
+          before { stub_const('Datadog::Core::LIBDATADOG_API_FAILURE', 'Failed to load') }
+
+          it 'logs warning and returns nil' do
+            expect(logger).to receive(:warn).with(/`libdatadog` is not loaded: "Failed to load"/)
+
+            expect(component).to be_nil
+          end
+        end
+
+        context 'when not running on MRI' do
+          before { stub_const('RUBY_ENGINE', 'jruby') }
+
+          it 'logs warning and returns nil' do
+            expect(logger).to receive(:warn).with(/MRI is required, but running on "jruby"/)
+
+            expect(component).to be_nil
+          end
+        end
       end
 
       context 'when remote configuration is disabled' do
         before { settings.remote.enabled = false }
 
         it 'logs warning and returns nil' do
-          expect(logger).to receive(:warn)
-            .with(/could not be enabled as Remote Configuration is currently disabled/)
+          expect(logger).to receive(:warn).with(/Remote Configuration is currently disabled/)
 
           expect(component).to be_nil
         end