From 611d2f3e65bc855ba7d25a550c324d64d3c5650c Mon Sep 17 00:00:00 2001
From: Dave Syer <dsyer@pivotal.io>
Date: Tue, 26 Apr 2016 09:15:14 +0100
Subject: [PATCH] Make discovery client more robust if there is no connection

The default behaviour is to know nothing if the client can't
connect to the cloud controller.
---
 .../CloudFoundryDiscoveryClient.java          | 23 +++++++++++++++----
 .../CloudFoundryDiscoveryClientTest.java      | 11 ++++++++-
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/spring-cloud-cloudfoundry-discovery/src/main/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClient.java b/spring-cloud-cloudfoundry-discovery/src/main/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClient.java
index c620cf5..4e02426 100644
--- a/spring-cloud-cloudfoundry-discovery/src/main/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClient.java
+++ b/spring-cloud-cloudfoundry-discovery/src/main/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClient.java
@@ -114,9 +114,16 @@ public class CloudFoundryDiscoveryClient implements DiscoveryClient {
 
 	@Override
 	public List<ServiceInstance> getInstances(String s) {
-		CloudApplication applications = this.cloudFoundryClient.getApplication(s);
-		return this.createServiceInstancesFromCloudApplications(
-				Collections.singletonList(applications));
+		try {
+			CloudApplication applications = this.cloudFoundryClient.getApplication(s);
+			return this.createServiceInstancesFromCloudApplications(
+					Collections.singletonList(applications));
+		}
+		catch (Exception e) {
+			log.warn("Could not get service instances: " + e.getClass() + " ("
+					+ e.getMessage() + ")");
+			return Collections.emptyList();
+		}
 	}
 
 	private boolean isRunning(CloudApplication ca) {
@@ -136,7 +143,15 @@ public class CloudFoundryDiscoveryClient implements DiscoveryClient {
 	@Override
 	public List<String> getServices() {
 		List<String> services = new ArrayList<>();
-		List<CloudApplication> applications = this.cloudFoundryClient.getApplications();
+		List<CloudApplication> applications;
+		try {
+			applications = this.cloudFoundryClient.getApplications();
+		}
+		catch (Exception e) {
+			log.warn("Could not get applications: " + e.getClass() + " ("
+					+ e.getMessage() + ")");
+			applications = Collections.emptyList();
+		}
 		Set<String> serviceIds = new HashSet<>();
 		for (CloudApplication ca : applications) {
 			if (isRunning(ca)) {
diff --git a/spring-cloud-cloudfoundry-discovery/src/test/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClientTest.java b/spring-cloud-cloudfoundry-discovery/src/test/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClientTest.java
index 62dfdbb..2b1804c 100644
--- a/spring-cloud-cloudfoundry-discovery/src/test/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClientTest.java
+++ b/spring-cloud-cloudfoundry-discovery/src/test/java/org/springframework/cloud/cloudfoundry/discovery/CloudFoundryDiscoveryClientTest.java
@@ -131,6 +131,15 @@ public class CloudFoundryDiscoveryClientTest {
 		assertEquals(instances.size(), 1);
 	}
 
+	@Test
+	public void testInstancesNotAvailable() {
+		given(this.cloudFoundryClient.getApplications()).willThrow(new RuntimeException("Planned"));
+
+		List<ServiceInstance> instances = this.cloudFoundryDiscoveryClient
+				.getInstances(this.hiServiceServiceId);
+		assertEquals(instances.size(), 0);
+	}
+
 	@Test
 	public void testLocalServiceInstanceRunning() {
 
@@ -170,7 +179,7 @@ public class CloudFoundryDiscoveryClientTest {
 	}
 
 	@Test
-	public void testLocalServiceInstanceNotFoundg() {
+	public void testLocalServiceInstanceNotFound() {
 
 		given(this.cloudFoundryClient.getApplicationInstances(this.cloudApplication))
 				.willThrow(new CloudFoundryException(HttpStatus.NOT_FOUND));