GH-503 - Prevent configuration properties from being proxied for observability.

We now avoid proxying configuration properties in the BeanPostProcessor that creates tracing proxies.

Author: odrotbohm

spring-modulith-observability/src/main/java/org/springframework/modulith/observability/ModuleTracingBeanPostProcessor.java

@@ -30,6 +30,7 @@
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
+import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.modulith.runtime.ApplicationModulesRuntime;
 import org.springframework.util.Assert;
 
@@ -97,8 +98,19 @@ public Object postProcessAfterInitialization(Object bean, String beanName) throw
 
 	private boolean isInfrastructureBean(String beanName) {
 
-		return factory.containsBean(beanName) &&
-				factory.getBeanDefinition(beanName).getRole() == BeanDefinition.ROLE_INFRASTRUCTURE;
+		if (!factory.containsBean(beanName)) {
+			return false;
+		}
+
+		if (factory.getBeanDefinition(beanName).getRole() == BeanDefinition.ROLE_INFRASTRUCTURE) {
+			return true;
+		}
+
+		if (factory.findAnnotationOnBean(beanName, ConfigurationProperties.class, false) != null) {
+			return true;
+		}
+
+		return false;
 	}
 
 	private Advisor getOrBuildAdvisor(ObservedModule module, ObservedModuleType type) {

spring-modulith-observability/src/test/java/example/sample/SampleProperties.java

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package example.sample;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * @author Oliver Drotbohm
+ */
+@ConfigurationProperties("sample")
+public class SampleProperties {}

spring-modulith-observability/src/test/java/org/springframework/modulith/observability/ModuleTracingBeanPostProcessorUnitTests.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.modulith.observability;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.*;
+import static org.mockito.Mockito.*;
+
+import example.sample.SampleProperties;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.beans.factory.support.RootBeanDefinition;
+import org.springframework.modulith.runtime.ApplicationModulesRuntime;
+
+/**
+ * Unit tests for {@link ModuleTracingBeanPostProcessor}.
+ *
+ * @author Oliver Drotbohm
+ */
+public class ModuleTracingBeanPostProcessorUnitTests {
+
+	@Test // GH-503
+	void doesNotProxyConfiguationProperties() {
+
+		var beanFactory = new DefaultListableBeanFactory();
+		beanFactory.registerBeanDefinition("properties", new RootBeanDefinition(SampleProperties.class));
+
+		var mock = mock(ApplicationModulesRuntime.class);
+		doReturn(SampleProperties.class).when(mock).getUserClass(any(), any());
+		doReturn(true).when(mock).isApplicationClass(any());
+
+		var processor = new ModuleTracingBeanPostProcessor(mock, () -> null, beanFactory);
+
+		var bean = new SampleProperties();
+		var result = processor.postProcessAfterInitialization(bean, "properties");
+
+		assertThat(result).isSameAs(bean);
+	}
+}