Add details to the StatusInfo

spring-boot-admin-server/src/main/java/de/codecentric/boot/admin/model/StatusInfo.java

 package de.codecentric.boot.admin.model;
 
 import java.io.Serializable;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Represents a certain status a certain time.
@@ -8,34 +11,51 @@ import java.io.Serializable;
  * @author Johannes Stelzer
  */
 public class StatusInfo implements Serializable {
-	private static final long serialVersionUID = 1L;
+	private static final long serialVersionUID = 2L;
 
 	private final String status;
 	private final long timestamp;
+	private final Map<String, ? extends Serializable> details;
 
-	protected StatusInfo(String status, long timestamp) {
+	protected StatusInfo(String status, long timestamp,
+			Map<String, ? extends Serializable> details) {
 		this.status = status.toUpperCase();
 		this.timestamp = timestamp;
+		this.details = details != null ? Collections.unmodifiableMap(new HashMap<>(details))
+				: Collections.<String, Serializable>emptyMap();
 	}
 
-	public static StatusInfo valueOf(String statusCode) {
-		return new StatusInfo(statusCode, System.currentTimeMillis());
+	public static StatusInfo valueOf(String statusCode,
+			Map<String, ? extends Serializable> details) {
+		return new StatusInfo(statusCode, System.currentTimeMillis(), details);
 	}
 
 	public static StatusInfo ofUnknown() {
-		return valueOf("UNKNOWN");
+		return valueOf("UNKNOWN", null);
 	}
 
 	public static StatusInfo ofUp() {
-		return valueOf("UP");
+		return ofUp(null);
 	}
 
 	public static StatusInfo ofDown() {
-		return valueOf("DOWN");
+		return ofDown(null);
 	}
 
 	public static StatusInfo ofOffline() {
-		return valueOf("OFFLINE");
+		return ofOffline(null);
+	}
+
+	public static StatusInfo ofUp(Map<String, ? extends Serializable> details) {
+		return valueOf("UP", details);
+	}
+
+	public static StatusInfo ofDown(Map<String, ? extends Serializable> details) {
+		return valueOf("DOWN", details);
+	}
+
+	public static StatusInfo ofOffline(Map<String, ? extends Serializable> details) {
+		return valueOf("OFFLINE", details);
 	}
 
 	public String getStatus() {
@@ -46,6 +66,10 @@ public class StatusInfo implements Serializable {
 		return timestamp;
 	}
 
+	public Map<String, ? extends Serializable> getDetails() {
+		return details;
+	}
+
 	@Override
 	public int hashCode() {
 		final int prime = 31;

spring-boot-admin-server/src/main/java/de/codecentric/boot/admin/registry/StatusUpdater.java

@@ -15,6 +15,8 @@
  */
 package de.codecentric.boot.admin.registry;
 
+import java.io.Serializable;
+import java.util.HashMap;
 import java.util.Map;
 
 import org.slf4j.Logger;
@@ -75,28 +77,36 @@ public class StatusUpdater implements ApplicationEventPublisherAware {
 
 		try {
 			@SuppressWarnings("unchecked")
-			ResponseEntity<Map<String, Object>> response = restTemplate.getForEntity(
-					application.getHealthUrl(), (Class<Map<String, Object>>) (Class<?>) Map.class);
+			ResponseEntity<Map<String, Serializable>> response = restTemplate.getForEntity(
+					application.getHealthUrl(),
+					(Class<Map<String, Serializable>>) (Class<?>) Map.class);
 			LOGGER.debug("/health for {} responded with {}", application, response);
 
 			if (response.hasBody() && response.getBody().get("status") instanceof String) {
-				return StatusInfo.valueOf((String) response.getBody().get("status"));
+				return StatusInfo.valueOf((String) response.getBody().get("status"),
+						response.getBody());
 			} else if (response.getStatusCode().is2xxSuccessful()) {
 				return StatusInfo.ofUp();
 			} else {
 				return StatusInfo.ofDown();
 			}
-
 		} catch (Exception ex) {
 			if ("OFFLINE".equals(application.getStatusInfo().getStatus())) {
 				LOGGER.debug("Couldn't retrieve status for {}", application, ex);
 			} else {
 				LOGGER.warn("Couldn't retrieve status for {}", application, ex);
 			}
-			return StatusInfo.ofOffline();
+			return StatusInfo.ofOffline(toDetails(ex));
 		}
 	}
 
+	protected Map<String, Serializable> toDetails(Exception ex) {
+		Map<String, Serializable> details = new HashMap<>();
+		details.put("message", ex.getMessage());
+		details.put("exception", ex.getClass().getName());
+		return details;
+	}
+
 	public void setStatusLifetime(long statusLifetime) {
 		this.statusLifetime = statusLifetime;
 	}

spring-boot-admin-server/src/test/java/de/codecentric/boot/admin/model/StatusInfoTest.java

@@ -11,8 +11,8 @@ public class StatusInfoTest {
 	@Test
 	public void test_equals_hashcode() {
 		StatusInfo up = StatusInfo.ofUp();
-		StatusInfo up2 = StatusInfo.valueOf("UP");
-		StatusInfo down = StatusInfo.valueOf("DOWN");
+		StatusInfo up2 = StatusInfo.ofUp();
+		StatusInfo down = StatusInfo.ofDown();
 
 		assertThat(up, is(up2));
 		assertThat(up, not(is(down)));

spring-boot-admin-server/src/test/java/de/codecentric/boot/admin/registry/StatusUpdaterTest.java

@@ -123,7 +123,7 @@ public class StatusUpdaterTest {
 		store.save(app1);
 
 		Application app2 = Application.create("foo").withId("id-2").withHealthUrl("health-2")
-				.withStatusInfo(StatusInfo.valueOf("UP")).build();
+				.withStatusInfo(StatusInfo.ofUp()).build();
 		store.save(app2);
 
 		when(template.getForEntity("health-2", Map.class))