Option to use ip-address of network-interface instead of hostname

spring-boot-admin-starter-client/src/main/java/de/codecentric/boot/admin/config/AdminClientProperties.java

@@ -16,6 +16,9 @@
 package de.codecentric.boot.admin.config;
 
 import java.net.InetAddress;
+import java.net.InterfaceAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
 import java.net.UnknownHostException;
 
 import org.springframework.beans.factory.annotation.Autowired;
@@ -64,6 +67,12 @@ public class AdminClientProperties implements ApplicationListener<ApplicationEve
 	@Value("${endpoints.health.id:health}")
 	private String healthEndpointId;
 
+	/**
+	 * If set, the address of the specified interface is used in url inference
+	 * instead of the hostname.
+	 */
+	private String useIpAddressOf = null;
+
 	@Autowired
 	private ManagementServerProperties management;
 
@@ -165,18 +174,14 @@ public class AdminClientProperties implements ApplicationListener<ApplicationEve
 		this.name = name;
 	}
 
-	private String getHostname() {
-		try {
-			return InetAddress.getLocalHost().getCanonicalHostName();
-		}
-		catch (UnknownHostException ex) {
-			throw new IllegalArgumentException(ex.getMessage(), ex);
-		}
+	public void setUseIpAddressOf(String useIpAddressOf) {
+		this.useIpAddressOf = useIpAddressOf;
 	}
 
 	private String createLocalUri(int port, String path) {
-		String scheme = server.getSsl() != null && server.getSsl().isEnabled() ? "https" : "http";
-		return append(scheme + "://" + getHostname() + ":" + port, path);
+		String scheme = server.getSsl() != null && server.getSsl().isEnabled() ? "https"
+				: "http";
+		return append(scheme + "://" + getHost() + ":" + port, path);
 	}
 
 	private String append(String uri, String path) {
@@ -188,4 +193,65 @@ public class AdminClientProperties implements ApplicationListener<ApplicationEve
 		String normPath = path.replaceFirst("^/+", "").replaceFirst("/+$", "");
 		return baseUri + "/" + normPath;
 	}
-}
+
+	private String getHost() {
+		if (useIpAddressOf == null) {
+			return getHostname();
+		} else {
+			return getHostIp();
+
+		}
+	}
+
+	private String getHostname() {
+		try {
+			return InetAddress.getLocalHost().getCanonicalHostName();
+		} catch (UnknownHostException ex) {
+			throw new IllegalArgumentException(ex.getMessage(), ex);
+		}
+	}
+
+	private String getHostIp() {
+		NetworkInterface nic;
+		try {
+			nic = NetworkInterface.getByName(useIpAddressOf);
+		} catch (SocketException ex) {
+			throw new IllegalArgumentException(ex.getMessage(), ex);
+		}
+
+		if (nic != null) {
+			InetAddress address = findIp(nic);
+			if (address != null) {
+				return address.getHostAddress();
+			}
+
+			throw new IllegalStateException(
+					"Couldn't determin InetAdress for network interface '"
+							+ useIpAddressOf + "'");
+		} else {
+			throw new IllegalArgumentException(
+					"Network interface"
+							+ useIpAddressOf
+							+ " not found! Please specify correct interface for spring.boot.admin.client.useIpAddressOf");
+		}
+	}
+
+	private InetAddress findIp(NetworkInterface nic) {
+		InetAddress candidate = null;
+
+		for (InterfaceAddress address : nic.getInterfaceAddresses()) {
+			if (!address.getAddress().isLoopbackAddress()) {
+				if (address.getAddress().isSiteLocalAddress()) {
+					return address.getAddress();
+				}
+				candidate = address.getAddress();
+			}
+		}
+
+		if (candidate != null) {
+			return candidate;
+		}
+
+		return null;
+	}
+}
\ No newline at end of file

spring-boot-admin-starter-client/src/test/java/de/codecentric/boot/admin/config/AdminClientPropertiesTest.java

@@ -111,7 +111,6 @@ public class AdminClientPropertiesTest {
 				+ ":8080/app"));
 	}
 
-
 	@Test
 	public void test_contextPath() {
 		load("server.context-path=app");
@@ -128,8 +127,6 @@ public class AdminClientPropertiesTest {
 				+ ":80/app"));
 	}
 
-
-
 	@Test
 	public void test_default() {
 		load();
@@ -145,7 +142,7 @@ public class AdminClientPropertiesTest {
 		assertThat(clientProperties.getServiceUrl(), is("http://" + getHostname()
 				+ ":8080"));
 	}
-	
+
 	@Test
 	public void testSsl() {
 		load("server.ssl.key-store=somefile.jks", "server.ssl.key-store-password=password");
@@ -162,6 +159,18 @@ public class AdminClientPropertiesTest {
 				+ ":8080"));
 	}
 
+	@Test(expected = IllegalArgumentException.class)
+	public void test_preferIpAddress_nic_not_exsts() {
+		load();
+		AdminClientProperties clientProperties = new AdminClientProperties();
+		clientProperties.setUseIpAddressOf("eth-not-exist");
+		context.getAutowireCapableBeanFactory().autowireBean(clientProperties);
+
+		publishServletContainerInitializedEvent(clientProperties, 8080, null);
+
+		clientProperties.getManagementUrl();
+	}
+
 	private String getHostname() {
 		try {
 			return InetAddress.getLocalHost().getCanonicalHostName();