add option to configure Consul check status considered as healthy

docs/src/main/asciidoc/_configprops.adoc

@@ -54,6 +54,7 @@
 |spring.cloud.consul.discovery.scheme | http | Whether to register an http or https service.
 |spring.cloud.consul.discovery.server-list-query-tags |  | Map of serviceId's -> tag to query for in server list. This allows filtering services by a single tag.
 |spring.cloud.consul.discovery.service-name |  | Service name.
+|spring.cloud.consul.discovery.status-considered-as-healthy | passing | The accepted health check states of instances used for routing in load balancer.
 |spring.cloud.consul.discovery.tags |  | Tags to use when registering service.
 |spring.cloud.consul.enabled | true | Is spring cloud consul enabled.
 |spring.cloud.consul.host | localhost | Consul agent hostname. Defaults to 'localhost'.

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

@@ -279,6 +279,20 @@ public String serviceUrl() {
 }
 ----
 
+==== Instances used by Load-balancer
+
+The load balancer will only use instances of a service with health checks in "passing" state by default. However Consul also offers the "warning" state, which you might still want to accept for routing. You can configure the accepted states via property `spring.cloud.consul.discovery.status-considered-as-healthy`, e.g.
+.application.yml
+----
+spring:
+  cloud:
+    consul:
+      discovery:
+        status-considered-as-healthy:
+          - PASSING
+          - WARNING
+----
+
 === Consul Catalog Watch
 
 The Consul Catalog Watch takes advantage of the ability of consul to https://www.consul.io/docs/agent/watches.html#services[watch services]. The Catalog Watch makes a blocking Consul HTTP API call to determine if any services have changed. If there is new service data a Heartbeat Event is published.

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/ConsulDiscoveryProperties.java

@@ -17,11 +17,15 @@
 package org.springframework.cloud.consul.discovery;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import com.ecwid.consul.v1.ConsistencyMode;
+import com.ecwid.consul.v1.health.model.Check;
 
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -160,6 +164,12 @@ public class ConsulDiscoveryProperties {
 	 */
 	private boolean queryPassing = false;
 
+	/**
+	 * List of status considered as healthy. Contains "passing" by default.
+	 */
+	private Set<Check.CheckStatus> statusConsideredAsHealthy = new HashSet(
+			Collections.singleton(Check.CheckStatus.PASSING));
+
 	/** Register as a service in consul. */
 	private boolean register = true;
 
@@ -470,10 +480,19 @@ public boolean isQueryPassing() {
 		return this.queryPassing;
 	}
 
+	public Set<Check.CheckStatus> getStatusConsideredAsHealthy() {
+		return statusConsideredAsHealthy;
+	}
+
 	public void setQueryPassing(boolean queryPassing) {
 		this.queryPassing = queryPassing;
 	}
 
+	public void setStatusConsideredAsHealthy(
+			Set<Check.CheckStatus> statusConsideredAsHealthy) {
+		this.statusConsideredAsHealthy = statusConsideredAsHealthy;
+	}
+
 	public boolean isRegister() {
 		return this.register;
 	}

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/ConsulServer.java

@@ -16,7 +16,9 @@
 
 package org.springframework.cloud.consul.discovery;
 
+import java.util.Collections;
 import java.util.Map;
+import java.util.Set;
 
 import com.ecwid.consul.v1.health.model.Check;
 import com.ecwid.consul.v1.health.model.HealthService;
@@ -33,11 +35,19 @@ public class ConsulServer extends Server {
 
 	private final HealthService service;
 
+	private final Set<Check.CheckStatus> statusConsideredAsHealthy;
+
 	private final Map<String, String> metadata;
 
 	public ConsulServer(final HealthService healthService) {
+		this(healthService, Collections.singleton(Check.CheckStatus.PASSING));
+	}
+
+	public ConsulServer(final HealthService healthService,
+			Set<Check.CheckStatus> statusConsideredAsHealthy) {
 		super(findHost(healthService), healthService.getService().getPort());
 		this.service = healthService;
+		this.statusConsideredAsHealthy = statusConsideredAsHealthy;
 		this.metadata = ConsulServerUtils.getMetadata(this.service);
 		this.metaInfo = new MetaInfo() {
 			@Override
@@ -79,7 +89,7 @@ public Map<String, String> getMetadata() {
 
 	public boolean isPassingChecks() {
 		for (Check check : this.service.getChecks()) {
-			if (check.getStatus() != Check.CheckStatus.PASSING) {
+			if (!statusConsideredAsHealthy.contains(check.getStatus())) {
 				return false;
 			}
 		}

spring-cloud-consul-discovery/src/main/java/org/springframework/cloud/consul/discovery/ConsulServerList.java

@@ -91,12 +91,13 @@ private List<ConsulServer> getServers() {
 	 * @param healthServices the initial list of servers from Consul. Guaranteed to be
 	 * non-empty list
 	 * @return ConsulServer instances
-	 * @see ConsulServer#ConsulServer(HealthService)
+	 * @see ConsulServer#ConsulServer(HealthService, java.util.Set)
 	 */
 	protected List<ConsulServer> transformResponse(List<HealthService> healthServices) {
 		List<ConsulServer> servers = new ArrayList<>();
 		for (HealthService service : healthServices) {
-			ConsulServer server = new ConsulServer(service);
+			ConsulServer server = new ConsulServer(service,
+				this.properties.getStatusConsideredAsHealthy());
 			if (server.getMetadata()
 					.containsKey(this.properties.getDefaultZoneMetadataName())) {
 				server.setZone(server.getMetadata()

spring-cloud-consul-discovery/src/test/java/org/springframework/cloud/consul/discovery/ConsulDiscoveryPropertiesTests.java

@@ -19,6 +19,7 @@
 import java.util.Collections;
 import java.util.Map;
 
+import com.ecwid.consul.v1.health.model.Check;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -95,4 +96,17 @@ public void testAddManagementTag() {
 				.containsOnly(ConsulDiscoveryProperties.MANAGEMENT, "newTag");
 	}
 
+	@Test
+	public void testConsiderStatusAsHealthyContainsPassingByDefault() {
+		assertThat(this.properties.getStatusConsideredAsHealthy())
+				.containsExactly(Check.CheckStatus.PASSING);
+	}
+
+	@Test
+	public void testConsiderWarningStatusAsHealthy() {
+		this.properties.getStatusConsideredAsHealthy().add(Check.CheckStatus.WARNING);
+		assertThat(this.properties.getStatusConsideredAsHealthy())
+				.containsExactlyInAnyOrder(Check.CheckStatus.WARNING, Check.CheckStatus.PASSING);
+	}
+
 }

spring-cloud-consul-discovery/src/test/java/org/springframework/cloud/consul/discovery/ConsulServerTest.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2013-2019 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.consul.discovery;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+import com.ecwid.consul.v1.health.model.Check;
+import com.ecwid.consul.v1.health.model.HealthService;
+import org.junit.Test;
+
+import static com.ecwid.consul.v1.health.model.Check.CheckStatus.CRITICAL;
+import static com.ecwid.consul.v1.health.model.Check.CheckStatus.PASSING;
+import static com.ecwid.consul.v1.health.model.Check.CheckStatus.WARNING;
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Christian Lorenz
+ */
+public class ConsulServerTest {
+
+	@Test
+	public void testIsPassingChecks() {
+		Set<Check.CheckStatus> acceptedStatus = new HashSet<>(
+				Arrays.asList(PASSING, WARNING));
+		assertThat(newServer(PASSING, acceptedStatus).isPassingChecks()).isTrue();
+		assertThat(newServer(WARNING, acceptedStatus).isPassingChecks()).isTrue();
+		assertThat(newServer(CRITICAL, acceptedStatus).isPassingChecks()).isFalse();
+	}
+
+	static ConsulServer newServer(Check.CheckStatus checkStatus,
+			Set<Check.CheckStatus> acceptedStatus) {
+		HealthService healthService = new HealthService();
+		HealthService.Node node = new HealthService.Node();
+		node.setAddress("nodeaddr" + checkStatus.name());
+		node.setNode("nodenode" + checkStatus.name());
+		healthService.setNode(node);
+		HealthService.Service service = new HealthService.Service();
+		service.setAddress("serviceaddr" + checkStatus.name());
+		service.setId("serviceid" + checkStatus.name());
+		service.setPort(8080);
+		service.setService("serviceservice" + checkStatus.name());
+		healthService.setService(service);
+		ArrayList<Check> checks = new ArrayList<>();
+		Check check = new Check();
+		check.setStatus(checkStatus);
+		checks.add(check);
+		healthService.setChecks(checks);
+		return new ConsulServer(healthService, acceptedStatus);
+	}
+
+}

spring-cloud-consul-discovery/src/test/java/org/springframework/cloud/consul/discovery/HealthServiceServerListFilterTests.java

@@ -17,17 +17,17 @@
 package org.springframework.cloud.consul.discovery;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
-import com.ecwid.consul.v1.health.model.Check;
-import com.ecwid.consul.v1.health.model.HealthService;
 import com.netflix.loadbalancer.Server;
 import org.junit.Test;
 
 import static com.ecwid.consul.v1.health.model.Check.CheckStatus.CRITICAL;
 import static com.ecwid.consul.v1.health.model.Check.CheckStatus.PASSING;
 import static com.ecwid.consul.v1.health.model.Check.CheckStatus.WARNING;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.cloud.consul.discovery.ConsulServerTest.newServer;
 
 /**
  * @author Spencer Gibb
@@ -39,33 +39,13 @@ public void testGetFilteredListOfServers() {
 		HealthServiceServerListFilter filter = new HealthServiceServerListFilter();
 
 		ArrayList<Server> servers = new ArrayList<>();
-		servers.add(newServer(PASSING));
-		servers.add(newServer(PASSING));
-		servers.add(newServer(CRITICAL));
-		servers.add(newServer(WARNING));
+		servers.add(newServer(PASSING, Collections.singleton(PASSING)));
+		servers.add(newServer(PASSING, Collections.singleton(PASSING)));
+		servers.add(newServer(CRITICAL, Collections.singleton(PASSING)));
+		servers.add(newServer(WARNING, Collections.singleton(PASSING)));
 
 		List<Server> filtered = filter.getFilteredListOfServers(servers);
 		assertThat(filtered).as("wrong # of filtered servers").hasSize(2);
 	}
 
-	private ConsulServer newServer(Check.CheckStatus checkStatus) {
-		HealthService healthService = new HealthService();
-		HealthService.Node node = new HealthService.Node();
-		node.setAddress("nodeaddr" + checkStatus.name());
-		node.setNode("nodenode" + checkStatus.name());
-		healthService.setNode(node);
-		HealthService.Service service = new HealthService.Service();
-		service.setAddress("serviceaddr" + checkStatus.name());
-		service.setId("serviceid" + checkStatus.name());
-		service.setPort(8080);
-		service.setService("serviceservice" + checkStatus.name());
-		healthService.setService(service);
-		ArrayList<Check> checks = new ArrayList<>();
-		Check check = new Check();
-		check.setStatus(checkStatus);
-		checks.add(check);
-		healthService.setChecks(checks);
-		return new ConsulServer(healthService);
-	}
-
 }