feat: Adds RestTemplate default ConnectTimeout / ConnectRequestTimeout (#4148)

docs/src/main/asciidoc/spring-cloud-netflix.adoc

@@ -112,6 +112,19 @@ NOTE: Because of a limitation in Eureka, it is not possible to support per-serve
 
 If you want to customize the RestTemplate used by the Eureka HTTP Client you may want to create a bean of `EurekaClientHttpRequestFactorySupplier` and provide your own logic for generating a `ClientHttpRequestFactory` instance.
 
+All default timeout-related properties for RestTemplate used by the Eureka HTTP Client are set to infinite. Therefore, to specify the timeout values, you must specify the value directly with the properties in `eureka.client.rest-template-timeout`. (All timeout properties are in milliseconds.)
+
+.application.yml
+[source,yaml]
+----
+eureka:
+  client:
+    rest-template-timeout:
+      connect-timeout: 5000
+      connect-request-timeout: 8000
+      socket-timeout: 10000
+----
+
 === Status Page and Health Indicator
 
 The status page and health indicators for a Eureka instance default to `/info` and `/health` respectively, which are the default locations of useful endpoints in a Spring Boot Actuator application.

spring-cloud-netflix-eureka-client/src/main/java/org/springframework/cloud/netflix/eureka/RestTemplateTimeoutProperties.java

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2013-2022 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.netflix.eureka;
+
+import java.util.Objects;
+
+import org.apache.http.client.config.RequestConfig;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.cloud.netflix.eureka.http.RestTemplateEurekaHttpClient;
+import org.springframework.web.client.RestTemplate;
+
+/**
+ * Properties for configuring timeouts used in {@link RestTemplate} required by
+ * {@link RestTemplateEurekaHttpClient}.
+ *
+ * @author Jiwon Jeon
+ * @since 4.0.0
+ */
+@ConfigurationProperties("eureka.client.rest-template-timeout")
+public class RestTemplateTimeoutProperties {
+
+	/**
+	 * Default values are set to -1 according to {@link RequestConfig .DEFAULT}.
+	 */
+	private int connectTimeout = -1;
+
+	private int connectRequestTimeout = -1;
+
+	private int socketTimeout = -1;
+
+	public int getConnectTimeout() {
+		return connectTimeout;
+	}
+
+	public int getConnectRequestTimeout() {
+		return connectRequestTimeout;
+	}
+
+	public int getSocketTimeout() {
+		return socketTimeout;
+	}
+
+	public void setConnectTimeout(int connectTimeout) {
+		this.connectTimeout = connectTimeout;
+	}
+
+	public void setConnectRequestTimeout(int connectRequestTimeout) {
+		this.connectRequestTimeout = connectRequestTimeout;
+	}
+
+	public void setSocketTimeout(int socketTimeout) {
+		this.socketTimeout = socketTimeout;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) {
+			return true;
+		}
+		if (o == null || getClass() != o.getClass()) {
+			return false;
+		}
+
+		RestTemplateTimeoutProperties that = (RestTemplateTimeoutProperties) o;
+
+		return connectTimeout == that.connectTimeout && connectRequestTimeout == that.connectRequestTimeout
+				&& socketTimeout == that.socketTimeout;
+	}
+
+	@Override
+	public int hashCode() {
+		return Objects.hash(connectTimeout, connectRequestTimeout, socketTimeout);
+	}
+
+	@Override
+	public String toString() {
+		return "RestTemplateTimeoutProperties{" + ", connectTimeout=" + connectTimeout + ", connectRequestTimeout="
+				+ connectRequestTimeout + ", socketTimeout=" + socketTimeout + '}';
+	}
+
+}

spring-cloud-netflix-eureka-client/src/main/java/org/springframework/cloud/netflix/eureka/config/DiscoveryClientOptionalArgsConfiguration.java

@@ -31,9 +31,11 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClas
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.condition.SearchStrategy;
 import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.cloud.configuration.SSLContextFactory;
 import org.springframework.cloud.configuration.TlsProperties;
 import org.springframework.cloud.netflix.eureka.MutableDiscoveryClientOptionalArgs;
+import org.springframework.cloud.netflix.eureka.RestTemplateTimeoutProperties;
 import org.springframework.cloud.netflix.eureka.http.DefaultEurekaClientHttpRequestFactorySupplier;
 import org.springframework.cloud.netflix.eureka.http.EurekaClientHttpRequestFactorySupplier;
 import org.springframework.cloud.netflix.eureka.http.RestTemplateDiscoveryClientOptionalArgs;
@@ -46,6 +48,7 @@ import org.springframework.web.reactive.function.client.WebClient;
  * @author Daniel Lavoie
  */
 @Configuration(proxyBeanMethods = false)
+@EnableConfigurationProperties(RestTemplateTimeoutProperties.class)
 public class DiscoveryClientOptionalArgsConfiguration {
 
 	protected static final Log logger = LogFactory.getLog(DiscoveryClientOptionalArgsConfiguration.class);
@@ -75,8 +78,9 @@ public class DiscoveryClientOptionalArgsConfiguration {
 	@Bean
 	@ConditionalOnMissingBean
 	@ConditionalOnClass(name = "org.springframework.web.client.RestTemplate")
-	EurekaClientHttpRequestFactorySupplier defaultEurekaClientHttpRequestFactorySupplier() {
-		return new DefaultEurekaClientHttpRequestFactorySupplier();
+	EurekaClientHttpRequestFactorySupplier defaultEurekaClientHttpRequestFactorySupplier(
+			RestTemplateTimeoutProperties restTemplateTimeoutProperties) {
+		return new DefaultEurekaClientHttpRequestFactorySupplier(restTemplateTimeoutProperties);
 	}
 
 	@Bean

spring-cloud-netflix-eureka-client/src/main/java/org/springframework/cloud/netflix/eureka/http/DefaultEurekaClientHttpRequestFactorySupplier.java

@@ -19,10 +19,12 @@ package org.springframework.cloud.netflix.eureka.http;
 import javax.net.ssl.HostnameVerifier;
 import javax.net.ssl.SSLContext;
 
+import org.apache.http.client.config.RequestConfig;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.impl.client.HttpClients;
 
+import org.springframework.cloud.netflix.eureka.RestTemplateTimeoutProperties;
 import org.springframework.http.client.ClientHttpRequestFactory;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.lang.Nullable;
@@ -36,6 +38,16 @@ import org.springframework.lang.Nullable;
  */
 public class DefaultEurekaClientHttpRequestFactorySupplier implements EurekaClientHttpRequestFactorySupplier {
 
+	private final RestTemplateTimeoutProperties restTemplateTimeoutProperties;
+
+	public DefaultEurekaClientHttpRequestFactorySupplier() {
+		this.restTemplateTimeoutProperties = new RestTemplateTimeoutProperties();
+	}
+
+	public DefaultEurekaClientHttpRequestFactorySupplier(RestTemplateTimeoutProperties restTemplateTimeoutProperties) {
+		this.restTemplateTimeoutProperties = restTemplateTimeoutProperties;
+	}
+
 	@Override
 	public ClientHttpRequestFactory get(SSLContext sslContext, @Nullable HostnameVerifier hostnameVerifier) {
 		HttpClientBuilder httpClientBuilder = HttpClients.custom();
@@ -45,10 +57,20 @@ public class DefaultEurekaClientHttpRequestFactorySupplier implements EurekaClie
 		if (hostnameVerifier != null) {
 			httpClientBuilder = httpClientBuilder.setSSLHostnameVerifier(hostnameVerifier);
 		}
+		if (restTemplateTimeoutProperties != null) {
+			httpClientBuilder.setDefaultRequestConfig(buildRequestConfig());
+		}
+
 		CloseableHttpClient httpClient = httpClientBuilder.build();
 		HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();
 		requestFactory.setHttpClient(httpClient);
 		return requestFactory;
 	}
 
+	private RequestConfig buildRequestConfig() {
+		return RequestConfig.custom().setConnectTimeout(restTemplateTimeoutProperties.getConnectTimeout())
+				.setConnectionRequestTimeout(restTemplateTimeoutProperties.getConnectRequestTimeout())
+				.setSocketTimeout(restTemplateTimeoutProperties.getSocketTimeout()).build();
+	}
+
 }