Add ObservationRegistry support to ConfigClientRequestTemplateFactory

spring-cloud-config-client/pom.xml

@@ -58,6 +58,11 @@
 			<artifactId>spring-boot-starter-actuator</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-restclient</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-aspectj</artifactId>

spring-cloud-config-client/src/main/java/org/springframework/cloud/config/client/ConfigClientRequestTemplateFactory.java

@@ -26,6 +26,7 @@
 
 import javax.net.ssl.SSLContext;
 
+import io.micrometer.observation.ObservationRegistry;
 import org.apache.commons.logging.Log;
 import org.apache.hc.client5.http.classic.HttpClient;
 import org.apache.hc.client5.http.impl.classic.HttpClients;
@@ -35,6 +36,7 @@
 import org.apache.hc.core5.http.io.SocketConfig;
 import org.apache.hc.core5.util.Timeout;
 
+import org.springframework.boot.restclient.observation.ObservationRestTemplateCustomizer;
 import org.springframework.cloud.configuration.SSLContextFactory;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpRequest;
@@ -44,6 +46,7 @@
 import org.springframework.http.client.ClientHttpResponse;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.http.client.SimpleClientHttpRequestFactory;
+import org.springframework.http.client.observation.DefaultClientRequestObservationConvention;
 import org.springframework.web.client.RestTemplate;
 
 import static org.springframework.cloud.config.client.ConfigClientProperties.AUTHORIZATION;
@@ -54,9 +57,23 @@ public class ConfigClientRequestTemplateFactory {
 
 	private final ConfigClientProperties properties;
 
+	private final ObservationRestTemplateCustomizer observationRestTemplateCustomizer;
+
 	public ConfigClientRequestTemplateFactory(Log log, ConfigClientProperties properties) {
 		this.log = log;
 		this.properties = properties;
+		this.observationRestTemplateCustomizer = null;
+
+	}
+
+	public ConfigClientRequestTemplateFactory(Log log, ConfigClientProperties properties,
+			ObservationRegistry observationRegistry) {
+		this.log = log;
+		this.properties = properties;
+		this.observationRestTemplateCustomizer = observationRegistry != ObservationRegistry.NOOP
+				? new ObservationRestTemplateCustomizer(observationRegistry,
+						new DefaultClientRequestObservationConvention())
+				: null;
 	}
 
 	public Log getLog() {
@@ -83,6 +100,10 @@ public RestTemplate create() {
 			template.setInterceptors(Arrays.asList(new GenericRequestHeaderInterceptor(headers)));
 		}
 
+		if (observationRestTemplateCustomizer != null) {
+			observationRestTemplateCustomizer.customize(template);
+		}
+
 		return template;
 	}
 

spring-cloud-config-client/src/main/java/org/springframework/cloud/config/client/ConfigServerBootstrapper.java

@@ -19,6 +19,8 @@
 import java.util.function.BiFunction;
 import java.util.function.Function;
 
+import io.micrometer.observation.ObservationRegistry;
+
 import org.springframework.boot.bootstrap.BootstrapContext;
 import org.springframework.boot.bootstrap.BootstrapRegistry;
 import org.springframework.boot.bootstrap.BootstrapRegistry.InstanceSupplier;
@@ -35,6 +37,8 @@ public class ConfigServerBootstrapper implements BootstrapRegistryInitializer {
 
 	private LoaderInterceptor loaderInterceptor;
 
+	private ObservationRegistry observationRegistry;
+
 	static ConfigServerBootstrapper create() {
 		return new ConfigServerBootstrapper();
 	}
@@ -46,13 +50,22 @@ public ConfigServerBootstrapper withRestTemplateFactory(
 		return this;
 	}
 
+	public ConfigServerBootstrapper withObservationRegistry(ObservationRegistry observationRegistry) {
+		this.observationRegistry = observationRegistry;
+		return this;
+	}
+
 	public ConfigServerBootstrapper withLoaderInterceptor(LoaderInterceptor loaderInterceptor) {
 		this.loaderInterceptor = loaderInterceptor;
 		return this;
 	}
 
 	@Override
 	public void initialize(BootstrapRegistry registry) {
+
+		if (observationRegistry != null) {
+			registry.register(ObservationRegistry.class, InstanceSupplier.of(observationRegistry));
+		}
 		if (restTemplateFactory != null) {
 			registry.register(RestTemplate.class, restTemplateFactory::apply);
 		}

spring-cloud-config-client/src/main/java/org/springframework/cloud/config/client/ConfigServerConfigDataLocationResolver.java

@@ -21,6 +21,7 @@
 import java.util.Properties;
 import java.util.function.Supplier;
 
+import io.micrometer.observation.ObservationRegistry;
 import org.apache.commons.logging.Log;
 
 import org.springframework.boot.bootstrap.BootstrapRegistry;
@@ -241,7 +242,8 @@ public List<ConfigServerConfigDataResource> resolveProfileSpecific(
 					event.getBootstrapContext().get(ConfigClientProperties.class)));
 
 		bootstrapContext.registerIfAbsent(ConfigClientRequestTemplateFactory.class,
-				context -> new ConfigClientRequestTemplateFactory(log, context.get(ConfigClientProperties.class)));
+				context -> new ConfigClientRequestTemplateFactory(log, context.get(ConfigClientProperties.class),
+						context.getOrElse(ObservationRegistry.class, ObservationRegistry.NOOP)));
 
 		bootstrapContext.registerIfAbsent(RestTemplate.class, context -> {
 			ConfigClientRequestTemplateFactory factory = context.get(ConfigClientRequestTemplateFactory.class);

spring-cloud-config-client/src/test/java/org/springframework/cloud/config/client/ConfigClientRequestTemplateFactoryTests.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2026-present 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.cloud.config.client;
+
+import io.micrometer.observation.ObservationRegistry;
+import org.apache.commons.logging.LogFactory;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.web.client.RestTemplate;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Luccas Asaphe
+ *
+ */
+public class ConfigClientRequestTemplateFactoryTests {
+
+	@Test
+	void shouldInstrumentRestTemplateWhenObservationRegistryProvided() {
+		// 1. set up the factory
+		ConfigClientProperties properties = new ConfigClientProperties();
+		ObservationRegistry registry = ObservationRegistry.create();
+		ConfigClientRequestTemplateFactory factory = new ConfigClientRequestTemplateFactory(
+				LogFactory.getLog(getClass()), properties, registry);
+
+		// 2. create the RestTemplate
+		RestTemplate restTemplate = factory.create();
+
+		// 3. verify the observation registry
+		assertThat(restTemplate.getObservationRegistry()).isEqualTo(registry);
+	}
+
+	@Test
+	void shouldNotInstrumentRestTemplateWhenObservationRegistryNotProvided() {
+		// 1. set up the factory
+		ConfigClientProperties properties = new ConfigClientProperties();
+		ConfigClientRequestTemplateFactory factory = new ConfigClientRequestTemplateFactory(
+				LogFactory.getLog(getClass()), properties);
+
+		// 2. create the RestTemplate
+		RestTemplate restTemplate = factory.create();
+
+		// 3. verify the observation registry
+		assertThat(restTemplate.getObservationRegistry()).isEqualTo(ObservationRegistry.NOOP);
+	}
+
+	@Test
+	void shouldNotInstrumentRestTemplateWhenObservationRegistryIsNoop() {
+		// 1. set up the factory
+		ConfigClientProperties properties = new ConfigClientProperties();
+		ObservationRegistry registry = ObservationRegistry.NOOP;
+		ConfigClientRequestTemplateFactory factory = new ConfigClientRequestTemplateFactory(
+				LogFactory.getLog(getClass()), properties, registry);
+
+		// 2. create the RestTemplate
+		RestTemplate restTemplate = factory.create();
+
+		// 3. verify the observation registry
+		assertThat(restTemplate.getObservationRegistry()).isEqualTo(ObservationRegistry.NOOP);
+	}
+
+}

spring-cloud-config-client/src/test/java/org/springframework/cloud/config/client/ConfigServerConfigDataCustomizationIntegrationTests.java

@@ -18,6 +18,7 @@
 
 import java.util.Optional;
 
+import io.micrometer.observation.ObservationRegistry;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
@@ -91,6 +92,33 @@ void customizableRestTemplate() {
 		}
 	}
 
+	@Test
+	void customizableObservationRegistry() {
+		ConfigurableApplicationContext context = null;
+		try {
+			ObservationRegistry registry = ObservationRegistry.create();
+			context = new SpringApplicationBuilder(TestConfig.class)
+				.addBootstrapRegistryInitializer(ConfigServerBootstrapper.create().withObservationRegistry(registry))
+				.addBootstrapRegistryInitializer(reg -> reg.addCloseListener(event -> {
+					BootstrapContext bootstrapContext = event.getBootstrapContext();
+					ConfigurableListableBeanFactory beanFactory = event.getApplicationContext().getBeanFactory();
+
+					RestTemplate restTemplate = bootstrapContext.get(RestTemplate.class);
+					beanFactory.registerSingleton("holder", new RestTemplateHolder(restTemplate));
+				}))
+				.run("--spring.config.import=optional:configserver:");
+
+			RestTemplateHolder holder = context.getBean(RestTemplateHolder.class);
+			assertThat(holder).isNotNull();
+			assertThat(holder.restTemplate.getObservationRegistry()).isEqualTo(registry);
+		}
+		finally {
+			if (context != null) {
+				context.close();
+			}
+		}
+	}
+
 	CustomRestTemplate restTemplate(BootstrapContext context) {
 		ConfigClientProperties properties = context.get(ConfigClientProperties.class);
 		String custom = context.get(Binder.class).bind("custom.prop", String.class).orElse("default-custom-prop");