Provide more info in host Orchestrator REST API

13 files changed, 316 insertions, 23 deletions

diff --git a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceCluster.java b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceCluster.java
index d18ced478f1..e53058f40e3 100644
--- a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceCluster.java
+++ b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceCluster.java
@@ -1,9 +1,11 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.applicationmodel;
 
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 import java.util.Objects;
+import java.util.Optional;
 import java.util.Set;
 
 /**
@@ -16,6 +18,7 @@ public class ServiceCluster {
     private final ClusterId clusterId;
     private final ServiceType serviceType;
     private final Set<ServiceInstance> serviceInstances;
+    private Optional<ApplicationInstance> applicationInstance = Optional.empty();
 
     public ServiceCluster(ClusterId clusterId, ServiceType serviceType, Set<ServiceInstance> serviceInstances) {
         this.clusterId = clusterId;
@@ -38,12 +41,25 @@ public class ServiceCluster {
         return serviceInstances;
     }
 
+    @JsonIgnore
+    public void setApplicationInstance(ApplicationInstance applicationInstance) {
+        this.applicationInstance = Optional.of(applicationInstance);
+    }
+
+    @JsonIgnore
+    public ApplicationInstance getApplicationInstance() {
+        return applicationInstance.get();
+    }
+
     @Override
     public String toString() {
         return "ServiceCluster{" +
                 "clusterId=" + clusterId +
                 ", serviceType=" + serviceType +
                 ", serviceInstances=" + serviceInstances +
+                (applicationInstance.isPresent() ?
+                        ", applicationInstance=" + applicationInstance.get() :
+                        "") +
                 '}';
     }
 
@@ -54,12 +70,12 @@ public class ServiceCluster {
         ServiceCluster that = (ServiceCluster) o;
         return Objects.equals(clusterId, that.clusterId) &&
                 Objects.equals(serviceType, that.serviceType) &&
-                Objects.equals(serviceInstances, that.serviceInstances);
+                Objects.equals(serviceInstances, that.serviceInstances) &&
+                Objects.equals(applicationInstance, that.applicationInstance);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(clusterId, serviceType, serviceInstances);
+        return Objects.hash(clusterId, serviceType, serviceInstances, applicationInstance);
     }
-
 }
diff --git a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
index 2b31bb11ff7..4c802218b22 100644
--- a/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
+++ b/application-model/src/main/java/com/yahoo/vespa/applicationmodel/ServiceInstance.java
@@ -1,9 +1,11 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.applicationmodel;
 
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 import java.util.Objects;
+import java.util.Optional;
 
 /**
  * @author bjorncs
@@ -13,6 +15,7 @@ public class ServiceInstance {
     private final ConfigId configId;
     private final HostName hostName;
     private final ServiceStatus serviceStatus;
+    private Optional<ServiceCluster> serviceCluster = Optional.empty();
 
     public ServiceInstance(ConfigId configId, HostName hostName, ServiceStatus serviceStatus) {
         this.configId = configId;
@@ -35,12 +38,23 @@ public class ServiceInstance {
         return serviceStatus;
     }
 
+    @JsonIgnore
+    public void setServiceCluster(ServiceCluster serviceCluster) {
+        this.serviceCluster = Optional.of(serviceCluster);
+    }
+
+    @JsonIgnore
+    public ServiceCluster getServiceCluster() {
+        return serviceCluster.get();
+    }
+
     @Override
     public String toString() {
         return "ServiceInstance{" +
                 "configId=" + configId +
                 ", hostName=" + hostName +
                 ", serviceStatus=" + serviceStatus +
+                (serviceCluster.isPresent() ? ", serviceCluster=" + serviceCluster.get() : "") +
                 '}';
     }
 
@@ -51,12 +65,12 @@ public class ServiceInstance {
         ServiceInstance that = (ServiceInstance) o;
         return Objects.equals(configId, that.configId) &&
                 Objects.equals(hostName, that.hostName) &&
-                Objects.equals(serviceStatus, that.serviceStatus);
+                serviceStatus == that.serviceStatus &&
+                Objects.equals(serviceCluster, that.serviceCluster);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(configId, hostName, serviceStatus);
+        return Objects.hash(configId, hostName, serviceStatus, serviceCluster);
     }
-
 }
diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/testutils/OrchestratorMock.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/testutils/OrchestratorMock.java
index 19882f0a508..46d72974718 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/testutils/OrchestratorMock.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/testutils/OrchestratorMock.java
@@ -7,6 +7,7 @@ import com.yahoo.vespa.orchestrator.ApplicationIdNotFoundException;
 import com.yahoo.vespa.orchestrator.ApplicationStateChangeDeniedException;
 import com.yahoo.vespa.orchestrator.BatchHostNameNotFoundException;
 import com.yahoo.vespa.orchestrator.BatchInternalErrorException;
+import com.yahoo.vespa.orchestrator.Host;
 import com.yahoo.vespa.orchestrator.HostNameNotFoundException;
 import com.yahoo.vespa.orchestrator.OrchestrationException;
 import com.yahoo.vespa.orchestrator.Orchestrator;
@@ -29,6 +30,11 @@ public class OrchestratorMock implements Orchestrator {
     Set<ApplicationId> suspendedApplications = new HashSet<>();
 
     @Override
+    public Host getHost(HostName hostName) throws HostNameNotFoundException {
+        return null;
+    }
+
+    @Override
     public HostStatus getNodeStatus(HostName hostName) throws HostNameNotFoundException {
         return null;
     }
diff --git a/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/HostApi.java b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/HostApi.java
index 1c4d138acef..7f576f6c4e3 100644
--- a/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/HostApi.java
+++ b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/HostApi.java
@@ -14,7 +14,9 @@ import javax.ws.rs.PUT;
 import javax.ws.rs.Path;
 import javax.ws.rs.PathParam;
 import javax.ws.rs.Produces;
+import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.UriInfo;
 
 /**
  * Definition of Orchestrator's REST API for hosts.
@@ -38,7 +40,8 @@ public interface HostApi {
     @GET
     @Path("/{hostname}")
     @Produces(MediaType.APPLICATION_JSON)
-    GetHostResponse getHost(@PathParam("hostname") String hostNameString);
+    GetHostResponse getHost(@Context UriInfo uriInfo,
+                            @PathParam("hostname") String hostNameString);
 
     /**
      * Tweak internal Orchestrator state for host.
diff --git a/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/GetHostResponse.java b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/GetHostResponse.java
index 99489b345d4..38801c4c817 100644
--- a/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/GetHostResponse.java
+++ b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/GetHostResponse.java
@@ -2,27 +2,48 @@
 package com.yahoo.vespa.orchestrator.restapi.wire;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
+import java.util.List;
 import java.util.Objects;
 
 /*
  * @author andreer
  */
+@JsonIgnoreProperties(ignoreUnknown = true)
+@JsonInclude(JsonInclude.Include.NON_NULL)
 public class GetHostResponse {
 
     public static final String FIELD_NAME_HOSTNAME = "hostname";
     public static final String FIELD_NAME_STATE = "state";
+    public static final String FIELD_NAME_APPLICATION_URL = "applicationUrl";
+    public static final String FIELD_NAME_SERVICES = "services";
 
     private final String hostname;
     private final String state;
+    private final String applicationUrl;
+    private final List<HostService> services;
+
+    // Deprecated - kept for backwards compatibility until clients have migrated away
+    public GetHostResponse(String hostname, String state) {
+        this.hostname = hostname;
+        this.state = state;
+        this.applicationUrl = null;
+        this.services = null;
+    }
 
     @JsonCreator
     public GetHostResponse(
-            @JsonProperty(FIELD_NAME_HOSTNAME) final String hostname,
-            @JsonProperty(FIELD_NAME_STATE) final String state) {
+            @JsonProperty(FIELD_NAME_HOSTNAME) String hostname,
+            @JsonProperty(FIELD_NAME_STATE) String state,
+            @JsonProperty(FIELD_NAME_APPLICATION_URL) String applicationUrl,
+            @JsonProperty(FIELD_NAME_SERVICES) List<HostService> services) {
         this.hostname = hostname;
         this.state = state;
+        this.applicationUrl = applicationUrl;
+        this.services = services;
     }
 
     @JsonProperty(FIELD_NAME_HOSTNAME)
@@ -35,21 +56,29 @@ public class GetHostResponse {
         return state;
     }
 
-    @Override
-    public boolean equals(final Object o) {
-        if (!(o instanceof GetHostResponse)) {
-            return false;
-        }
+    @JsonProperty(FIELD_NAME_APPLICATION_URL)
+    public String applicationUrl() {
+        return applicationUrl;
+    }
 
-        final GetHostResponse other = (GetHostResponse) o;
-        if (!Objects.equals(this.hostname, other.hostname)) return false;
-        if (!Objects.equals(this.state, other.state)) return false;
+    @JsonProperty(FIELD_NAME_SERVICES)
+    public List<HostService> services() {
+        return services;
+    }
 
-        return true;
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        GetHostResponse that = (GetHostResponse) o;
+        return Objects.equals(hostname, that.hostname) &&
+                Objects.equals(state, that.state) &&
+                Objects.equals(applicationUrl, that.applicationUrl) &&
+                Objects.equals(services, that.services);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(hostname, state);
+        return Objects.hash(hostname, state, applicationUrl, services);
     }
 }
diff --git a/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/HostService.java b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/HostService.java
new file mode 100644
index 00000000000..70cc9187dd1
--- /dev/null
+++ b/orchestrator-restapi/src/main/java/com/yahoo/vespa/orchestrator/restapi/wire/HostService.java
@@ -0,0 +1,52 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.orchestrator.restapi.wire;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.util.Objects;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+@JsonInclude(JsonInclude.Include.NON_NULL)
+public class HostService {
+    @JsonProperty("clusterId")
+    public final String clusterId;
+
+    @JsonProperty("serviceType")
+    public final String serviceType;
+
+    @JsonProperty("configId")
+    public final String configId;
+
+    @JsonProperty("serviceStatus")
+    public final String serviceStatus;
+
+    @JsonCreator
+    public HostService(@JsonProperty("clusterId") String clusterId,
+                       @JsonProperty("serviceType") String serviceType,
+                       @JsonProperty("configId") String configId,
+                       @JsonProperty("serviceStatus") String serviceStatus) {
+        this.clusterId = clusterId;
+        this.serviceType = serviceType;
+        this.configId = configId;
+        this.serviceStatus = serviceStatus;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        HostService that = (HostService) o;
+        return Objects.equals(clusterId, that.clusterId) &&
+                Objects.equals(serviceType, that.serviceType) &&
+                Objects.equals(configId, that.configId) &&
+                Objects.equals(serviceStatus, that.serviceStatus);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(clusterId, serviceType, configId, serviceStatus);
+    }
+}
diff --git a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Host.java b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Host.java
new file mode 100644
index 00000000000..8e06f3b342a
--- /dev/null
+++ b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Host.java
@@ -0,0 +1,42 @@
+// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.orchestrator;
+
+import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
+import com.yahoo.vespa.orchestrator.status.HostStatus;
+
+import java.util.List;
+
+public class Host {
+    private final HostName hostName;
+    private final HostStatus hostStatus;
+    private final ApplicationInstanceReference applicationInstanceReference;
+    private final List<ServiceInstance> serviceInstances;
+
+    public Host(HostName hostName,
+                HostStatus hostStatus,
+                ApplicationInstanceReference applicationInstanceReference,
+                List<ServiceInstance> serviceInstances) {
+        this.hostName = hostName;
+        this.hostStatus = hostStatus;
+        this.applicationInstanceReference = applicationInstanceReference;
+        this.serviceInstances = serviceInstances;
+    }
+
+    public HostName getHostName() {
+        return hostName;
+    }
+
+    public HostStatus getHostStatus() {
+        return hostStatus;
+    }
+
+    public ApplicationInstanceReference getApplicationInstanceReference() {
+        return applicationInstanceReference;
+    }
+
+    public List<ServiceInstance> getServiceInstances() {
+        return serviceInstances;
+    }
+}
diff --git a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Orchestrator.java b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Orchestrator.java
index 9702b97dc28..ab61a51c418 100644
--- a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Orchestrator.java
+++ b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/Orchestrator.java
@@ -32,6 +32,12 @@ import java.util.Set;
 public interface Orchestrator {
 
     /**
+     * Get orchestrator information related to a host.
+     * @throws HostNameNotFoundException
+     */
+    Host getHost(HostName hostName) throws HostNameNotFoundException;
+
+    /**
      * Get the status of a given node. If no state is recorded
      * then this will return the status 'No Remarks'
      *
diff --git a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/OrchestratorImpl.java b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/OrchestratorImpl.java
index ef81a45fefe..dbc526bdf03 100644
--- a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/OrchestratorImpl.java
+++ b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/OrchestratorImpl.java
@@ -9,6 +9,7 @@ import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
 import com.yahoo.vespa.applicationmodel.ClusterId;
 import com.yahoo.vespa.applicationmodel.HostName;
 import com.yahoo.vespa.applicationmodel.ServiceCluster;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
 import com.yahoo.vespa.orchestrator.config.OrchestratorConfig;
 import com.yahoo.vespa.orchestrator.controller.ClusterControllerClient;
 import com.yahoo.vespa.orchestrator.controller.ClusterControllerClientFactory;
@@ -78,6 +79,20 @@ public class OrchestratorImpl implements Orchestrator {
     }
 
     @Override
+    public Host getHost(HostName hostName) throws HostNameNotFoundException {
+        ApplicationInstance applicationInstance = getApplicationInstance(hostName);
+        List<ServiceInstance> serviceInstances = applicationInstance
+                .serviceClusters().stream()
+                .flatMap(cluster -> cluster.serviceInstances().stream())
+                .filter(serviceInstance -> hostName.equals(serviceInstance.hostName()))
+                .collect(Collectors.toList());
+
+        HostStatus hostStatus = getNodeStatus(applicationInstance.reference(), hostName);
+
+        return new Host(hostName, hostStatus, applicationInstance.reference(), serviceInstances);
+    }
+
+    @Override
     public HostStatus getNodeStatus(HostName hostName) throws HostNameNotFoundException {
         return getNodeStatus(getApplicationInstance(hostName).reference(), hostName);
     }
diff --git a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/resources/HostResource.java b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/resources/HostResource.java
index b5ef2822761..198f291266b 100644
--- a/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/resources/HostResource.java
+++ b/orchestrator/src/main/java/com/yahoo/vespa/orchestrator/resources/HostResource.java
@@ -4,12 +4,14 @@ package com.yahoo.vespa.orchestrator.resources;
 import com.yahoo.container.jaxrs.annotation.Component;
 import com.yahoo.log.LogLevel;
 import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.orchestrator.Host;
 import com.yahoo.vespa.orchestrator.HostNameNotFoundException;
 import com.yahoo.vespa.orchestrator.OrchestrationException;
 import com.yahoo.vespa.orchestrator.Orchestrator;
 import com.yahoo.vespa.orchestrator.policy.HostStateChangeDeniedException;
 import com.yahoo.vespa.orchestrator.restapi.HostApi;
 import com.yahoo.vespa.orchestrator.restapi.wire.GetHostResponse;
+import com.yahoo.vespa.orchestrator.restapi.wire.HostService;
 import com.yahoo.vespa.orchestrator.restapi.wire.HostStateChangeDenialReason;
 import com.yahoo.vespa.orchestrator.restapi.wire.PatchHostRequest;
 import com.yahoo.vespa.orchestrator.restapi.wire.PatchHostResponse;
@@ -24,7 +26,11 @@ import javax.ws.rs.Path;
 import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
+import javax.ws.rs.core.UriInfo;
+import java.net.URI;
+import java.util.List;
 import java.util.logging.Logger;
+import java.util.stream.Collectors;
 
 /**
  * @author oyving
@@ -41,11 +47,29 @@ public class HostResource implements HostApi {
     }
 
     @Override
-    public GetHostResponse getHost(String hostNameString) {
+    public GetHostResponse getHost(UriInfo uriInfo, String hostNameString) {
         HostName hostName = new HostName(hostNameString);
         try {
-            HostStatus status = orchestrator.getNodeStatus(hostName);
-            return new GetHostResponse(hostName.s(), status.name());
+            Host host = orchestrator.getHost(hostName);
+
+            URI applicationUri = uriInfo.getBaseUriBuilder()
+                    .path(InstanceResource.class)
+                    .path(host.getApplicationInstanceReference().asString())
+                    .build();
+
+            List<HostService> hostServices = host.getServiceInstances().stream()
+                    .map(serviceInstance -> new HostService(
+                            serviceInstance.getServiceCluster().clusterId().s(),
+                            serviceInstance.getServiceCluster().serviceType().s(),
+                            serviceInstance.configId().s(),
+                            serviceInstance.serviceStatus().name()))
+                    .collect(Collectors.toList());
+
+            return new GetHostResponse(
+                    host.getHostName().s(),
+                    host.getHostStatus().name(),
+                    applicationUri.toString(),
+                    hostServices);
         } catch (HostNameNotFoundException e) {
             log.log(LogLevel.INFO, "Host not found: " + hostName);
             throw new NotFoundException(e);
diff --git a/orchestrator/src/test/java/com/yahoo/vespa/orchestrator/OrchestratorImplTest.java b/orchestrator/src/test/java/com/yahoo/vespa/orchestrator/OrchestratorImplTest.java
index 8cf9d343134..76d9398c44e 100644
--- a/orchestrator/src/test/java/com/yahoo/vespa/orchestrator/OrchestratorImplTest.java
+++ b/orchestrator/src/test/java/com/yahoo/vespa/orchestrator/OrchestratorImplTest.java
@@ -3,14 +3,25 @@ package com.yahoo.vespa.orchestrator;
 
 import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.vespa.applicationmodel.ApplicationInstance;
+import com.yahoo.vespa.applicationmodel.ApplicationInstanceId;
 import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.ClusterId;
+import com.yahoo.vespa.applicationmodel.ConfigId;
 import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceCluster;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
+import com.yahoo.vespa.applicationmodel.ServiceStatus;
+import com.yahoo.vespa.applicationmodel.ServiceType;
+import com.yahoo.vespa.applicationmodel.TenantId;
 import com.yahoo.vespa.orchestrator.config.OrchestratorConfig;
+import com.yahoo.vespa.orchestrator.controller.ClusterControllerClientFactory;
 import com.yahoo.vespa.orchestrator.controller.ClusterControllerClientFactoryMock;
 import com.yahoo.vespa.orchestrator.policy.BatchHostStateChangeDeniedException;
 import com.yahoo.vespa.orchestrator.policy.HostStateChangeDeniedException;
 import com.yahoo.vespa.orchestrator.status.HostStatus;
 import com.yahoo.vespa.orchestrator.status.InMemoryStatusService;
+import com.yahoo.vespa.orchestrator.status.ReadOnlyStatusRegistry;
+import com.yahoo.vespa.orchestrator.status.StatusService;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -18,6 +29,9 @@ import org.mockito.InOrder;
 
 import java.util.Arrays;
 import java.util.Iterator;
+import java.util.Optional;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import static com.yahoo.vespa.orchestrator.status.ApplicationInstanceStatus.ALLOWED_TO_BE_DOWN;
 import static com.yahoo.vespa.orchestrator.status.ApplicationInstanceStatus.NO_REMARKS;
@@ -31,7 +45,9 @@ import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.when;
 
 /**
  * Test Orchestrator with a mock backend (the InMemoryStatusService)
@@ -139,7 +155,6 @@ public class OrchestratorImplTest {
         assertThat(orchestrator.getApplicationInstanceStatus(app2), is(ALLOWED_TO_BE_DOWN));
     }
 
-
     @Test
     public void application_suspend_sets_application_nodes_in_maintenance_and_allowed_to_be_down() throws Exception {
         // Pre condition
@@ -281,6 +296,63 @@ public class OrchestratorImplTest {
         order.verifyNoMoreInteractions();
     }
 
+    @Test
+    public void testGetHost() throws Exception {
+        ClusterControllerClientFactory clusterControllerClientFactory =
+                mock(ClusterControllerClientFactory.class);
+        StatusService statusService = mock(StatusService.class);
+        InstanceLookupService lookupService = mock(InstanceLookupService.class);
+
+        orchestrator = new OrchestratorImpl(
+                clusterControllerClientFactory,
+                statusService,
+                new OrchestratorConfig(new OrchestratorConfig.Builder()),
+                lookupService);
+
+        HostName hostName = new HostName("host.yahoo.com");
+        TenantId tenantId = new TenantId("tenant");
+        ApplicationInstanceId applicationInstanceId =
+                new ApplicationInstanceId("applicationInstanceId");
+        ApplicationInstanceReference reference = new ApplicationInstanceReference(
+                tenantId,
+                applicationInstanceId);
+
+        ApplicationInstance applicationInstance =
+                new ApplicationInstance(
+                        tenantId,
+                        applicationInstanceId,
+                        Stream.of(new ServiceCluster(
+                                new ClusterId("clusterId"),
+                                new ServiceType("serviceType"),
+                                Stream.of(
+                                        new ServiceInstance(
+                                                new ConfigId("configId1"),
+                                                hostName,
+                                                ServiceStatus.UP),
+                                new ServiceInstance(
+                                        new ConfigId("configId2"),
+                                        hostName,
+                                        ServiceStatus.NOT_CHECKED))
+                                        .collect(Collectors.toSet())))
+                        .collect(Collectors.toSet()));
+
+        when(lookupService.findInstanceByHost(hostName))
+                .thenReturn(Optional.of(applicationInstance));
+
+        ReadOnlyStatusRegistry readOnlyStatusRegistry = mock(ReadOnlyStatusRegistry.class);
+        when(statusService.forApplicationInstance(reference))
+                .thenReturn(readOnlyStatusRegistry);
+        when(readOnlyStatusRegistry.getHostStatus(hostName))
+                .thenReturn(HostStatus.ALLOWED_TO_BE_DOWN);
+
+        Host host = orchestrator.getHost(hostName);
+
+        assertEquals(reference, host.getApplicationInstanceReference());
+        assertEquals(hostName, host.getHostName());
+        assertEquals(HostStatus.ALLOWED_TO_BE_DOWN, host.getHostStatus());
+        assertEquals(2, host.getServiceInstances().size());
+    }
+
     private boolean isInMaintenance(ApplicationId appId, HostName hostName) throws ApplicationIdNotFoundException {
         for (ApplicationInstance app : DummyInstanceLookupService.getApplications()) {
             if (app.reference().equals(OrchestratorUtil.toApplicationInstanceReference(appId, new DummyInstanceLookupService()))) {
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ConfigServerApplication.java b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ConfigServerApplication.java
index 1a48ba870fb..7a76c072076 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ConfigServerApplication.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ConfigServerApplication.java
@@ -48,6 +48,12 @@ public class ConfigServerApplication {
                 APPLICATION_INSTANCE_ID,
                 serviceClusters);
 
+        // Fill back-references
+        serviceCluster.setApplicationInstance(applicationInstance);
+        for (ServiceInstance serviceInstance : serviceCluster.serviceInstances()) {
+            serviceInstance.setServiceCluster(serviceCluster);
+        }
+
         return applicationInstance;
     }
 }
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ModelGenerator.java b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ModelGenerator.java
index d9f019ade63..9716846dea4 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ModelGenerator.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ModelGenerator.java
@@ -101,6 +101,14 @@ public class ModelGenerator {
                 toApplicationInstanceId(applicationInfo, zone),
                 serviceClusters);
 
+        // Fill back-references
+        for (ServiceCluster serviceCluster : applicationInstance.serviceClusters()) {
+            serviceCluster.setApplicationInstance(applicationInstance);
+            for (ServiceInstance serviceInstance : serviceCluster.serviceInstances()) {
+                serviceInstance.setServiceCluster(serviceCluster);
+            }
+        }
+
         return applicationInstance;
     }