Moved to more specific methods on ServiceMonitor

11 files changed, 308 insertions, 79 deletions

diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModel.java b/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModel.java
index 1cfb70560b8..aa0b9e81c44 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModel.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModel.java
@@ -9,6 +9,7 @@ import com.yahoo.vespa.service.monitor.DuperModelListener;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.TreeMap;
 import java.util.logging.Logger;
 
@@ -49,6 +50,10 @@ public class DuperModel {
         }
     }
 
+    public Optional<ApplicationInfo> getApplicationInfo(ApplicationId applicationId) {
+        return Optional.ofNullable(applications.get(applicationId));
+    }
+
     public List<ApplicationInfo> getApplicationInfos() {
         logger.log(LogLevel.DEBUG, "Applications in duper model: " + applications.values().size());
         return List.copyOf(applications.values());
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModelManager.java b/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModelManager.java
index 15c461c7f59..9c819d89fb2 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModelManager.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/duper/DuperModelManager.java
@@ -173,6 +173,12 @@ public class DuperModelManager implements DuperModelProvider, DuperModelInfraApi
         }
     }
 
+    public Optional<ApplicationInfo> getApplicationInfo(ApplicationId applicationId) {
+        synchronized (monitor) {
+            return duperModel.getApplicationInfo(applicationId);
+        }
+    }
+
     public List<ApplicationInfo> getApplicationInfos() {
         synchronized (monitor) {
             return duperModel.getApplicationInfos();
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ApplicationInstanceGenerator.java b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ApplicationInstanceGenerator.java
index 5cc2d538c24..db15c2789d5 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ApplicationInstanceGenerator.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ApplicationInstanceGenerator.java
@@ -5,9 +5,13 @@ import com.yahoo.config.model.api.ApplicationInfo;
 import com.yahoo.config.model.api.HostInfo;
 import com.yahoo.config.model.api.ServiceInfo;
 import com.yahoo.config.provision.ApplicationId;
+import com.yahoo.config.provision.ApplicationName;
+import com.yahoo.config.provision.InstanceName;
+import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.Zone;
 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;
@@ -24,7 +28,9 @@ import com.yahoo.vespa.service.monitor.ServiceStatusProvider;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Set;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
 /**
@@ -37,23 +43,100 @@ public class ApplicationInstanceGenerator {
 
     private final ApplicationInfo applicationInfo;
     private final Zone zone;
-    private ApplicationId configServerApplicationId;
+
+    // This is cheating a bit, but we don't expect DuperModel's config server application ID to be different.
+    // We do this to avoid passing through the ID through multiple levels.
+    private static ApplicationId configServerApplicationId = new ConfigServerApplication().getApplicationId();
 
     public ApplicationInstanceGenerator(ApplicationInfo applicationInfo, Zone zone) {
         this.applicationInfo = applicationInfo;
         this.zone = zone;
-
-        // This is cheating a bit, but we don't expect DuperModel's config server application ID to be different.
-        // We do this to avoid passing through the ID through multiple levels.
-        this.configServerApplicationId = new ConfigServerApplication().getApplicationId();
     }
 
     public ApplicationInstance makeApplicationInstance(ServiceStatusProvider serviceStatusProvider) {
+        return makeApplicationInstanceLimitedToHosts(serviceStatusProvider, hostname -> true);
+    }
+
+    public static ServiceId getServiceId(ApplicationInfo applicationInfo, ServiceInfo serviceInfo) {
+        return new ServiceId(
+                applicationInfo.getApplicationId(),
+                getClusterId(serviceInfo),
+                toServiceType(serviceInfo),
+                toConfigId(serviceInfo));
+    }
+
+    public ApplicationInstanceReference toApplicationInstanceReference() {
+        TenantId tenantId = new TenantId(applicationInfo.getApplicationId().tenant().toString());
+        ApplicationInstanceId applicationInstanceId = toApplicationInstanceId(applicationInfo.getApplicationId(), zone);
+        return new ApplicationInstanceReference(tenantId, applicationInstanceId);
+    }
+
+    public boolean containsHostname(HostName hostname) {
+        return applicationInfo.getModel().getHosts().stream()
+                .map(HostInfo::getHostname)
+                .anyMatch(hostnameString -> Objects.equals(hostnameString, hostname.s()));
+    }
+
+    public ApplicationInstance makeApplicationInstanceLimitedTo(
+            HostName hostname, ServiceStatusProvider serviceStatusProvider) {
+        return makeApplicationInstanceLimitedToHosts(
+                serviceStatusProvider, candidateHostname -> candidateHostname.equals(hostname));
+    }
+
+    /** Reverse of toApplicationInstanceId, put in this file because it its inverse is. */
+    public static ApplicationId toApplicationId(ApplicationInstanceReference reference) {
+
+        String appNameStr = reference.asString();
+        String[] appNameParts = appNameStr.split(":");
+
+        // Env, region and instance seems to be optional due to the hardcoded config server app
+        // Assume here that first two are tenant and application name.
+        if (appNameParts.length == 2) {
+            return ApplicationId.from(TenantName.from(appNameParts[0]),
+                    ApplicationName.from(appNameParts[1]),
+                    InstanceName.defaultName());
+        }
+
+        // Other normal application should have 5 parts.
+        if (appNameParts.length != 5)  {
+            throw new IllegalArgumentException("Application reference not valid (not 5 parts): " + reference);
+        }
+
+        return ApplicationId.from(TenantName.from(appNameParts[0]),
+                ApplicationName.from(appNameParts[1]),
+                InstanceName.from(appNameParts[4]));
+    }
+
+    private static ApplicationInstanceId toApplicationInstanceId(ApplicationId applicationId, Zone zone) {
+        if (applicationId.equals(configServerApplicationId)) {
+            // Removing this historical discrepancy would break orchestration during rollout.
+            // An alternative may be to use a feature flag and flip it between releases,
+            // once that's available.
+            return new ApplicationInstanceId(applicationId.application().value());
+        } else {
+            return new ApplicationInstanceId(String.format("%s:%s:%s:%s",
+                    applicationId.application().value(),
+                    zone.environment().value(),
+                    zone.region().value(),
+                    applicationId.instance().value()));
+        }
+    }
+
+    private static ClusterId getClusterId(ServiceInfo serviceInfo) {
+        return new ClusterId(serviceInfo.getProperty(CLUSTER_ID_PROPERTY_NAME).orElse(""));
+    }
+
+    private ApplicationInstance makeApplicationInstanceLimitedToHosts(ServiceStatusProvider serviceStatusProvider,
+                                                                      Predicate<HostName> includeHostPredicate) {
         Map<ServiceClusterKey, Set<ServiceInstance>> groupedServiceInstances = new HashMap<>();
 
         for (HostInfo host : applicationInfo.getModel().getHosts()) {
             HostName hostName = new HostName(host.getHostname());
 
+            if (!includeHostPredicate.test(hostName)) {
+                continue;
+            }
+
             for (ServiceInfo serviceInfo : host.getServices()) {
                 ServiceClusterKey serviceClusterKey = toServiceClusterKey(serviceInfo);
 
@@ -77,10 +160,8 @@ public class ApplicationInstanceGenerator {
                         entry.getValue()))
                 .collect(Collectors.toSet());
 
-        ApplicationInstance applicationInstance = new ApplicationInstance(
-                new TenantId(applicationInfo.getApplicationId().tenant().toString()),
-                toApplicationInstanceId(applicationInfo, zone),
-                serviceClusters);
+        ApplicationInstanceReference reference = toApplicationInstanceReference();
+        ApplicationInstance applicationInstance = new ApplicationInstance(reference, serviceClusters);
 
         // Fill back-references
         for (ServiceCluster serviceCluster : applicationInstance.serviceClusters()) {
@@ -106,33 +187,6 @@ public class ApplicationInstanceGenerator {
         return new ServiceInstance(configId, hostName, status);
     }
 
-    private ApplicationInstanceId toApplicationInstanceId(ApplicationInfo applicationInfo, Zone zone) {
-        if (applicationInfo.getApplicationId().equals(configServerApplicationId)) {
-            // Removing this historical discrepancy would break orchestration during rollout.
-            // An alternative may be to use a feature flag and flip it between releases,
-            // once that's available.
-            return new ApplicationInstanceId(applicationInfo.getApplicationId().application().value());
-        } else {
-            return new ApplicationInstanceId(String.format("%s:%s:%s:%s",
-                    applicationInfo.getApplicationId().application().value(),
-                    zone.environment().value(),
-                    zone.region().value(),
-                    applicationInfo.getApplicationId().instance().value()));
-        }
-    }
-
-    public static ServiceId getServiceId(ApplicationInfo applicationInfo, ServiceInfo serviceInfo) {
-        return new ServiceId(
-                applicationInfo.getApplicationId(),
-                getClusterId(serviceInfo),
-                toServiceType(serviceInfo),
-                toConfigId(serviceInfo));
-    }
-
-    public static ClusterId getClusterId(ServiceInfo serviceInfo) {
-        return new ClusterId(serviceInfo.getProperty(CLUSTER_ID_PROPERTY_NAME).orElse(""));
-    }
-
     private static ServiceClusterKey toServiceClusterKey(ServiceInfo serviceInfo) {
         ClusterId clusterId = getClusterId(serviceInfo);
         ServiceType serviceType = toServiceType(serviceInfo);
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ModelGenerator.java b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ModelGenerator.java
index a6bf41d6c9b..45a9d1c77c5 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ModelGenerator.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ModelGenerator.java
@@ -5,11 +5,15 @@ import com.yahoo.config.model.api.ApplicationInfo;
 import com.yahoo.config.provision.Zone;
 import com.yahoo.vespa.applicationmodel.ApplicationInstance;
 import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
 import com.yahoo.vespa.service.monitor.ServiceModel;
 import com.yahoo.vespa.service.monitor.ServiceStatusProvider;
 
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
@@ -18,6 +22,11 @@ import java.util.stream.Collectors;
  */
 public class ModelGenerator {
     public static final String CLUSTER_ID_PROPERTY_NAME = "clustername";
+    private final Zone zone;
+
+    public ModelGenerator(Zone zone) {
+        this.zone = zone;
+    }
 
     /**
      * Create service model based primarily on super model.
@@ -25,7 +34,6 @@ public class ModelGenerator {
      * If the configServerhosts is non-empty, a config server application is added.
      */
     public ServiceModel toServiceModel(List<ApplicationInfo> allApplicationInfos,
-                                       Zone zone,
                                        ServiceStatusProvider serviceStatusProvider) {
         Map<ApplicationInstanceReference, ApplicationInstance> applicationInstances =
                 allApplicationInfos.stream()
@@ -36,4 +44,48 @@ public class ModelGenerator {
         return new ServiceModel(applicationInstances);
     }
 
+    public Set<ApplicationInstanceReference> toApplicationInstanceReferenceSet(List<ApplicationInfo> infos) {
+        return infos.stream()
+                .map(info -> new ApplicationInstanceGenerator(info, zone).toApplicationInstanceReference())
+                .collect(Collectors.toSet());
+    }
+
+    public Optional<ApplicationInstance> toApplication(List<ApplicationInfo> applicationInfos,
+                                                       HostName hostname,
+                                                       ServiceStatusProvider serviceStatusProvider) {
+        for (var applicationInfo : applicationInfos) {
+            var generator = new ApplicationInstanceGenerator(applicationInfo, zone);
+            if (generator.containsHostname(hostname)) {
+                return Optional.of(generator.makeApplicationInstance(serviceStatusProvider));
+            }
+        }
+
+        return Optional.empty();
+    }
+
+    public ApplicationInstance toApplication(ApplicationInfo applicationInfo,
+                                             ServiceStatusProvider serviceStatusProvider) {
+        var generator = new ApplicationInstanceGenerator(applicationInfo, zone);
+        return generator.makeApplicationInstance(serviceStatusProvider);
+    }
+
+    public List<ServiceInstance> toServices(List<ApplicationInfo> applicationInfos,
+                                            HostName hostname,
+                                            ServiceStatusProvider serviceStatusProvider) {
+        for (var applicationInfo : applicationInfos) {
+            var generator = new ApplicationInstanceGenerator(applicationInfo, zone);
+            ApplicationInstance applicationInstance = generator.makeApplicationInstanceLimitedTo(
+                    hostname, serviceStatusProvider);
+
+            List<ServiceInstance> serviceInstances = applicationInstance.serviceClusters().stream()
+                    .flatMap(cluster -> cluster.serviceInstances().stream())
+                    .collect(Collectors.toList());
+
+            if (serviceInstances.size() > 0) {
+                return serviceInstances;
+            }
+        }
+
+        return List.of();
+    }
 }
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelCache.java b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelCache.java
index 1b37555a554..29b2832efd0 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelCache.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelCache.java
@@ -4,6 +4,7 @@ package com.yahoo.vespa.service.model;
 
 import com.yahoo.jdisc.Timer;
 import com.yahoo.vespa.service.monitor.ServiceModel;
+import com.yahoo.vespa.service.monitor.ServiceMonitor;
 
 import java.util.function.Supplier;
 
@@ -12,12 +13,11 @@ import java.util.function.Supplier;
  *
  * @author hakonhall
  */
-public class ServiceModelCache implements Supplier<ServiceModel> {
+public class ServiceModelCache implements ServiceMonitor {
     public static final long EXPIRY_MILLIS = 10000;
 
     private final Supplier<ServiceModel> expensiveSupplier;
     private final Timer timer;
-    private final boolean useCache;
 
     private volatile ServiceModel snapshot;
     private boolean updatePossiblyInProgress = false;
@@ -25,18 +25,13 @@ public class ServiceModelCache implements Supplier<ServiceModel> {
     private final Object updateMonitor = new Object();
     private long snapshotMillis;
 
-    public ServiceModelCache(Supplier<ServiceModel> expensiveSupplier, Timer timer, boolean useCache) {
+    public ServiceModelCache(Supplier<ServiceModel> expensiveSupplier, Timer timer) {
         this.expensiveSupplier = expensiveSupplier;
         this.timer = timer;
-        this.useCache = useCache;
     }
 
     @Override
-    public ServiceModel get() {
-        if (!useCache) {
-            return expensiveSupplier.get();
-        }
-
+    public ServiceModel getServiceModelSnapshot() {
         if (snapshot == null) {
             synchronized (updateMonitor) {
                 if (snapshot == null) {
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelProvider.java b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelProvider.java
index c6947810fa0..641bc5ca7ff 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelProvider.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceModelProvider.java
@@ -2,33 +2,40 @@
 package com.yahoo.vespa.service.model;
 
 import com.yahoo.config.model.api.ApplicationInfo;
+import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.config.provision.Zone;
+import com.yahoo.vespa.applicationmodel.ApplicationInstance;
+import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
+import com.yahoo.vespa.service.duper.DuperModelManager;
 import com.yahoo.vespa.service.monitor.ServiceModel;
+import com.yahoo.vespa.service.monitor.ServiceMonitor;
 import com.yahoo.vespa.service.monitor.ServiceStatusProvider;
-import com.yahoo.vespa.service.manager.MonitorManager;
-import com.yahoo.vespa.service.duper.DuperModelManager;
 
 import java.util.List;
-import java.util.function.Supplier;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
 
 /**
  * An uncached supplier of ServiceModel based on the DuperModel and MonitorManager.
  *
  * @author hakonhall
  */
-public class ServiceModelProvider implements Supplier<ServiceModel> {
+public class ServiceModelProvider implements ServiceMonitor {
     private final ServiceMonitorMetrics metrics;
     private final DuperModelManager duperModelManager;
     private final ModelGenerator modelGenerator;
     private final Zone zone;
-    private final MonitorManager monitorManager;
+    private final ServiceStatusProvider serviceStatusProvider;
 
-    public ServiceModelProvider(MonitorManager monitorManager,
+    public ServiceModelProvider(ServiceStatusProvider serviceStatusProvider,
                                 ServiceMonitorMetrics metrics,
                                 DuperModelManager duperModelManager,
                                 ModelGenerator modelGenerator,
                                 Zone zone) {
-        this.monitorManager = monitorManager;
+        this.serviceStatusProvider = serviceStatusProvider;
         this.metrics = metrics;
         this.duperModelManager = duperModelManager;
         this.modelGenerator = modelGenerator;
@@ -36,13 +43,46 @@ public class ServiceModelProvider implements Supplier<ServiceModel> {
     }
 
     @Override
-    public ServiceModel get() {
+    public ServiceModel getServiceModelSnapshot() {
         try (LatencyMeasurement measurement = metrics.startServiceModelSnapshotLatencyMeasurement()) {
-            // WARNING: The monitor manager may be out-of-sync with duper model (no locking)
-            List<ApplicationInfo> applicationInfos = duperModelManager.getApplicationInfos();
-
-            return modelGenerator.toServiceModel(applicationInfos, zone, (ServiceStatusProvider) monitorManager);
+            return modelGenerator.toServiceModel(applicationInfos(), serviceStatusProvider);
         }
     }
 
+    @Override
+    public Set<ApplicationInstanceReference> getAllApplicationInstanceReferences() {
+        return modelGenerator.toApplicationInstanceReferenceSet(applicationInfos());
+    }
+
+    @Override
+    public Optional<ApplicationInstance> getApplication(HostName hostname) {
+        // TODO(hakonhall): Lookup the applicationInfo from the hostname.
+        return modelGenerator.toApplication(applicationInfos(), hostname, serviceStatusProvider);
+    }
+
+    @Override
+    public Optional<ApplicationInstance> getApplication(ApplicationInstanceReference reference) {
+        return getApplicationInfo(reference)
+                .map(applicationInfo -> modelGenerator.toApplication(applicationInfo, serviceStatusProvider));
+    }
+
+    @Override
+    public List<ServiceInstance> getServiceInstancesOn(HostName hostname) {
+        // TODO(hakonhall): Lookup the applicationInfo from the hostname.
+        return modelGenerator.toServices(applicationInfos(), hostname, serviceStatusProvider);
+    }
+
+    @Override
+    public Map<HostName, List<ServiceInstance>> getServicesByHostname() {
+        return getServiceModelSnapshot().getServiceInstancesByHostName();
+    }
+
+    private Optional<ApplicationInfo> getApplicationInfo(ApplicationInstanceReference reference) {
+        ApplicationId applicationId = ApplicationInstanceGenerator.toApplicationId(reference);
+        return duperModelManager.getApplicationInfo(applicationId);
+    }
+
+    private List<ApplicationInfo> applicationInfos() {
+        return duperModelManager.getApplicationInfos();
+    }
 }
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceMonitorImpl.java b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceMonitorImpl.java
index 67b4e890c29..a37a52f775e 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceMonitorImpl.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/model/ServiceMonitorImpl.java
@@ -5,6 +5,10 @@ import com.google.inject.Inject;
 import com.yahoo.config.provision.Zone;
 import com.yahoo.jdisc.Metric;
 import com.yahoo.jdisc.Timer;
+import com.yahoo.vespa.applicationmodel.ApplicationInstance;
+import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
 import com.yahoo.vespa.flags.FlagSource;
 import com.yahoo.vespa.flags.Flags;
 import com.yahoo.vespa.service.duper.DuperModelManager;
@@ -12,9 +16,14 @@ import com.yahoo.vespa.service.manager.UnionMonitorManager;
 import com.yahoo.vespa.service.monitor.ServiceModel;
 import com.yahoo.vespa.service.monitor.ServiceMonitor;
 
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+
 public class ServiceMonitorImpl implements ServiceMonitor {
 
-    private final ServiceModelCache serviceModelProvider;
+    private final ServiceMonitor delegate;
 
     @Inject
     public ServiceMonitorImpl(DuperModelManager duperModelManager,
@@ -25,19 +34,47 @@ public class ServiceMonitorImpl implements ServiceMonitor {
                               FlagSource flagSource) {
         duperModelManager.registerListener(monitorManager);
 
-        ServiceModelProvider uncachedServiceModelProvider = new ServiceModelProvider(
+        ServiceMonitor serviceMonitor = new ServiceModelProvider(
                 monitorManager,
                 new ServiceMonitorMetrics(metric, timer),
                 duperModelManager,
-                new ModelGenerator(),
+                new ModelGenerator(zone),
                 zone);
-        boolean cache = Flags.SERVICE_MODEL_CACHE.bindTo(flagSource).value();
-        serviceModelProvider = new ServiceModelCache(uncachedServiceModelProvider, timer, cache);
+
+        if (Flags.SERVICE_MODEL_CACHE.bindTo(flagSource).value()) {
+            delegate = new ServiceModelCache(serviceMonitor::getServiceModelSnapshot, timer);
+        } else {
+            delegate = serviceMonitor;
+        }
     }
 
     @Override
     public ServiceModel getServiceModelSnapshot() {
-        return serviceModelProvider.get();
+        return delegate.getServiceModelSnapshot();
+    }
+
+    @Override
+    public Set<ApplicationInstanceReference> getAllApplicationInstanceReferences() {
+        return delegate.getAllApplicationInstanceReferences();
+    }
+
+    @Override
+    public Optional<ApplicationInstance> getApplication(HostName hostname) {
+        return delegate.getApplication(hostname);
     }
 
+    @Override
+    public Optional<ApplicationInstance> getApplication(ApplicationInstanceReference reference) {
+        return delegate.getApplication(reference);
+    }
+
+    @Override
+    public List<ServiceInstance> getServiceInstancesOn(HostName hostname) {
+        return delegate.getServiceInstancesOn(hostname);
+    }
+
+    @Override
+    public Map<HostName, List<ServiceInstance>> getServicesByHostname() {
+        return delegate.getServicesByHostname();
+    }
 }
diff --git a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ServiceMonitor.java b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ServiceMonitor.java
index 49539c61e5d..8ad77213bc1 100644
--- a/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ServiceMonitor.java
+++ b/service-monitor/src/main/java/com/yahoo/vespa/service/monitor/ServiceMonitor.java
@@ -1,6 +1,17 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.service.monitor;
 
+import com.yahoo.vespa.applicationmodel.ApplicationInstance;
+import com.yahoo.vespa.applicationmodel.ApplicationInstanceReference;
+import com.yahoo.vespa.applicationmodel.HostName;
+import com.yahoo.vespa.applicationmodel.ServiceInstance;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+
 /**
  * The service monitor interface. A service monitor provides up to date information about the liveness status
  * (up, down or not known) of each service instance in a Vespa zone
@@ -12,7 +23,37 @@ public interface ServiceMonitor {
     /**
      * Returns a ServiceModel which contains the current liveness status (up, down or unknown) of all instances
      * of all services of all clusters of all applications in a zone.
+     * Deprecated: Please use the more specific methods below.
      */
     ServiceModel getServiceModelSnapshot();
 
+    default Set<ApplicationInstanceReference> getAllApplicationInstanceReferences() {
+        return getServiceModelSnapshot().getAllApplicationInstances().keySet();
+    }
+
+    default Optional<ApplicationInstance> getApplication(HostName hostname) {
+        return Optional.ofNullable(getServiceModelSnapshot().getApplicationsByHostName().get(hostname));
+    }
+
+    default Optional<ApplicationInstance> getApplication(ApplicationInstanceReference reference) {
+        return getServiceModelSnapshot().getApplicationInstance(reference);
+    }
+
+    default List<ServiceInstance> getServiceInstancesOn(HostName hostname) {
+        ApplicationInstance application = getServiceModelSnapshot().getApplicationsByHostName().get(hostname);
+        if (application == null) {
+            return List.of();
+        }
+
+        return application
+                .serviceClusters().stream()
+                .flatMap(cluster -> cluster.serviceInstances().stream())
+                .filter(serviceInstance -> hostname.equals(serviceInstance.hostName()))
+                .collect(Collectors.toList());
+    }
+
+    default Map<HostName, List<ServiceInstance>> getServicesByHostname() {
+        return getServiceModelSnapshot().getServiceInstancesByHostName();
+    }
+
 }
diff --git a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ModelGeneratorTest.java b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ModelGeneratorTest.java
index ce13cf60082..7be4ff38a7f 100644
--- a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ModelGeneratorTest.java
+++ b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ModelGeneratorTest.java
@@ -38,9 +38,9 @@ public class ModelGeneratorTest {
 
     @Test
     public void toApplicationModel() throws Exception {
-        ModelGenerator modelGenerator = new ModelGenerator();
-
         Zone zone = new Zone(Environment.from(ENVIRONMENT), RegionName.from(REGION));
+        ModelGenerator modelGenerator = new ModelGenerator(zone);
+
 
         SlobrokMonitorManagerImpl slobrokMonitorManager = mock(SlobrokMonitorManagerImpl.class);
         when(slobrokMonitorManager.getStatus(any(), any(), any(), any()))
@@ -49,7 +49,6 @@ public class ModelGeneratorTest {
         ServiceModel serviceModel =
                 modelGenerator.toServiceModel(
                         getExampleApplicationInfos(),
-                        zone,
                         slobrokMonitorManager);
 
         Map<ApplicationInstanceReference,
diff --git a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelCacheTest.java b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelCacheTest.java
index c2314be1e0f..21c6a49cc18 100644
--- a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelCacheTest.java
+++ b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelCacheTest.java
@@ -16,27 +16,27 @@ import static org.mockito.Mockito.when;
 
 public class ServiceModelCacheTest {
     @SuppressWarnings("unchecked")
-    private final Supplier<ServiceModel> rawSupplier = mock(Supplier.class);
+    private final Supplier<ServiceModel> expensiveServiceMonitor = mock(Supplier.class);
     private final Timer timer = mock(Timer.class);
-    private final ServiceModelCache cache = new ServiceModelCache(rawSupplier, timer, true);
+    private final ServiceModelCache cache = new ServiceModelCache(expensiveServiceMonitor, timer);
 
     @Test
     public void sanityCheck() {
         ServiceModel serviceModel = mock(ServiceModel.class);
-        when(rawSupplier.get()).thenReturn(serviceModel);
+        when(expensiveServiceMonitor.get()).thenReturn(serviceModel);
 
         long timeMillis = 0;
         when(timer.currentTimeMillis()).thenReturn(timeMillis);
 
         // Will always populate cache the first time
-        ServiceModel actualServiceModel = cache.get();
+        ServiceModel actualServiceModel = cache.getServiceModelSnapshot();
         assertTrue(actualServiceModel == serviceModel);
-        verify(rawSupplier, times(1)).get();
+        verify(expensiveServiceMonitor, times(1)).get();
 
         // Cache hit
         timeMillis += ServiceModelCache.EXPIRY_MILLIS / 2;
         when(timer.currentTimeMillis()).thenReturn(timeMillis);
-        actualServiceModel = cache.get();
+        actualServiceModel = cache.getServiceModelSnapshot();
         assertTrue(actualServiceModel == serviceModel);
 
         // Cache expired
@@ -44,17 +44,17 @@ public class ServiceModelCacheTest {
         when(timer.currentTimeMillis()).thenReturn(timeMillis);
 
         ServiceModel serviceModel2 = mock(ServiceModel.class);
-        when(rawSupplier.get()).thenReturn(serviceModel2);
+        when(expensiveServiceMonitor.get()).thenReturn(serviceModel2);
 
-        actualServiceModel = cache.get();
+        actualServiceModel = cache.getServiceModelSnapshot();
         assertTrue(actualServiceModel == serviceModel2);
         // '2' because it's cumulative with '1' from the first times(1).
-        verify(rawSupplier, times(2)).get();
+        verify(expensiveServiceMonitor, times(2)).get();
 
         // Cache hit #2
         timeMillis += 1;
         when(timer.currentTimeMillis()).thenReturn(timeMillis);
-        actualServiceModel = cache.get();
+        actualServiceModel = cache.getServiceModelSnapshot();
         assertTrue(actualServiceModel == serviceModel2);
     }
 }
\ No newline at end of file
diff --git a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelProviderTest.java b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelProviderTest.java
index 13f6da1534d..f34d61970ef 100644
--- a/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelProviderTest.java
+++ b/service-monitor/src/test/java/com/yahoo/vespa/service/model/ServiceModelProviderTest.java
@@ -37,8 +37,8 @@ public class ServiceModelProviderTest {
                 .collect(Collectors.toList());
         when(duperModelManager.getApplicationInfos()).thenReturn(applications);
 
-        ServiceModel serviceModel = provider.get();
+        ServiceModel serviceModel = provider.getServiceModelSnapshot();
         verify(duperModelManager, times(1)).getApplicationInfos();
-        verify(modelGenerator).toServiceModel(applications, zone, slobrokMonitorManager);
+        verify(modelGenerator).toServiceModel(applications, slobrokMonitorManager);
     }
 }
\ No newline at end of file