Handle case where GITLAB_PROMETHEUS_METRICS_ENABLED is non boolean value by defaulting to false

db/fixtures/production/010_settings.rb

@@ -20,7 +20,7 @@ end
 
 if ENV['GITLAB_PROMETHEUS_METRICS_ENABLED'].present?
   settings = Gitlab::CurrentSettings.current_application_settings
-  value = Gitlab::Utils.to_boolean(ENV['GITLAB_PROMETHEUS_METRICS_ENABLED'])
+  value = Gitlab::Utils.to_boolean(ENV['GITLAB_PROMETHEUS_METRICS_ENABLED']) || false
   settings.prometheus_metrics_enabled = value
   save(settings, 'Prometheus metrics enabled flag')
 end

spec/db/production/settings_spec.rb

@@ -42,5 +42,17 @@ describe 'seed production settings', lib: true do
         expect(settings.prometheus_metrics_enabled).to eq(false)
       end
     end
+
+    context 'GITLAB_PROMETHEUS_METRICS_ENABLED is false' do
+      before do
+        stub_env('GITLAB_PROMETHEUS_METRICS_ENABLED', '')
+      end
+
+      it 'prometheus_metrics_enabled is set to false' do
+        load(settings_file)
+
+        expect(settings.prometheus_metrics_enabled).to eq(false)
+      end
+    end
   end
 end