From b0b4916d3c9a74585efd3d401c0b6c89d0b09311 Mon Sep 17 00:00:00 2001
From: Dave Syer <dsyer@pivotal.io>
Date: Mon, 27 Jul 2015 17:54:22 +0100
Subject: [PATCH] If user configures hostname for eureka client, do not refresh
 it

Fixes gh-463
---
 .../eureka/EurekaInstanceConfigBean.java      | 20 ++++--
 .../eureka/EurekaInstanceConfigBeanTests.java | 61 ++++++++++++++++---
 2 files changed, 68 insertions(+), 13 deletions(-)

diff --git a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBean.java b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBean.java
index cf1b2917..92969e1f 100644
--- a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBean.java
+++ b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBean.java
@@ -113,15 +113,20 @@ public class EurekaInstanceConfigBean implements EurekaInstanceConfig {
 	}
 
 	private HostInfo initHostInfo() {
-		HostInfo info = new HostInfo();
+		this.hostInfo = this.hostInfo == null ? new HostInfo() : this.hostInfo;
 		try {
-			info.ipAddress = InetAddress.getLocalHost().getHostAddress();
-			info.hostname = InetAddress.getLocalHost().getHostName();
+			this.hostInfo.ipAddress = InetAddress.getLocalHost().getHostAddress();
+			this.hostInfo.hostname = InetAddress.getLocalHost().getHostName();
 		}
 		catch (UnknownHostException ex) {
 			logger.error("Cannot get host info", ex);
 		}
-		return info;
+		return this.hostInfo;
+	}
+
+	public void setHostname(String hostname) {
+		this.hostname = hostname;
+		this.hostInfo.override = true;
 	}
 
 	@Override
@@ -129,18 +134,21 @@ public class EurekaInstanceConfigBean implements EurekaInstanceConfig {
 		if (refresh) {
 			this.hostInfo = initHostInfo();
 			this.ipAddress = this.hostInfo.ipAddress;
-			this.hostname = this.hostInfo.hostname;
+			if (!this.hostInfo.override) {
+				this.hostname = this.hostInfo.hostname;
+			}
 		}
 		return this.preferIpAddress ? this.ipAddress : this.hostname;
 	}
 
 	private final class HostInfo {
+		public boolean override;
 		private String ipAddress;
 		private String hostname;
 	}
 
 	private final class IdentifyingDataCenterInfo implements DataCenterInfo,
-			UniqueIdentifier {
+	UniqueIdentifier {
 
 		@Getter
 		@Setter
diff --git a/spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBeanTests.java b/spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBeanTests.java
index 8f31e98f..da18bb30 100644
--- a/spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBeanTests.java
+++ b/spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/eureka/EurekaInstanceConfigBeanTests.java
@@ -16,30 +16,46 @@
 
 package org.springframework.cloud.netflix.eureka;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.springframework.boot.test.EnvironmentTestUtils.addEnvironment;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
 import org.junit.After;
+import org.junit.Before;
 import org.junit.Test;
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.test.util.ReflectionTestUtils;
 
 import com.netflix.appinfo.InstanceInfo.InstanceStatus;
 import com.netflix.appinfo.UniqueIdentifier;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.springframework.boot.test.EnvironmentTestUtils.addEnvironment;
-
 /**
  * @author Dave Syer
  */
 public class EurekaInstanceConfigBeanTests {
 
 	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+	private String hostName;
+
+	@Before
+	public void init() {
+		try {
+			this.hostName = InetAddress.getLocalHost().getHostName();
+		}
+		catch (UnknownHostException e) {
+			// Ignore (test must be running in a restricted environment)
+		}
+	}
 
 	@After
-	public void init() {
+	public void clear() {
 		if (this.context != null) {
 			this.context.close();
 		}
@@ -67,6 +83,37 @@ public class EurekaInstanceConfigBeanTests {
 		assertEquals(8888, getInstanceConfig().getNonSecurePort());
 	}
 
+	@Test
+	public void initialHostName() {
+		addEnvironment(this.context, "eureka.instance.appGroupName=mygroup");
+		setupContext();
+		if (this.hostName != null) {
+			assertEquals(this.hostName, getInstanceConfig().getHostname());
+		}
+	}
+
+	@Test
+	public void refreshHostName() {
+		addEnvironment(this.context, "eureka.instance.appGroupName=mygroup");
+		setupContext();
+		ReflectionTestUtils.setField(getInstanceConfig(), "hostname", "marvin");
+		assertEquals("marvin", getInstanceConfig().getHostname());
+		getInstanceConfig().getHostName(true);
+		if (this.hostName != null) {
+			assertEquals(this.hostName, getInstanceConfig().getHostname());
+		}
+	}
+
+	@Test
+	public void refreshHostNameWhenSetByUser() {
+		addEnvironment(this.context, "eureka.instance.appGroupName=mygroup");
+		setupContext();
+		getInstanceConfig().setHostname("marvin");
+		assertEquals("marvin", getInstanceConfig().getHostname());
+		getInstanceConfig().getHostName(true);
+		assertEquals("marvin", getInstanceConfig().getHostname());
+	}
+
 	@Test
 	public void testDefaultInitialStatus() {
 		setupContext();
@@ -89,7 +136,7 @@ public class EurekaInstanceConfigBeanTests {
 	}
 
 	@Test
-	public void testPerferIpAddress() throws Exception {
+	public void testPreferIpAddress() throws Exception {
 		addEnvironment(this.context, "eureka.instance.preferIpAddress:true");
 		setupContext();
 		EurekaInstanceConfigBean instance = getInstanceConfig();
@@ -99,7 +146,7 @@ public class EurekaInstanceConfigBeanTests {
 	}
 
 	@Test
-	public void testPerferIpAddressInDatacenter() throws Exception {
+	public void testPreferIpAddressInDatacenter() throws Exception {
 		addEnvironment(this.context, "eureka.instance.preferIpAddress:true");
 		setupContext();
 		EurekaInstanceConfigBean instance = getInstanceConfig();