Add flag for deactivating routing for an application

2 files changed, 29 insertions, 3 deletions

diff --git a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisioner.java b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisioner.java
index 1c2f6664258..5ff78c53f8a 100644
--- a/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisioner.java
+++ b/node-repository/src/main/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisioner.java
@@ -10,6 +10,9 @@ import com.yahoo.config.provision.NodeType;
 import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.exception.LoadBalancerServiceException;
 import com.yahoo.transaction.NestedTransaction;
+import com.yahoo.vespa.flags.BooleanFlag;
+import com.yahoo.vespa.flags.FetchVector;
+import com.yahoo.vespa.flags.PermanentFlags;
 import com.yahoo.vespa.hosted.provision.Node;
 import com.yahoo.vespa.hosted.provision.NodeList;
 import com.yahoo.vespa.hosted.provision.NodeRepository;
@@ -51,11 +54,13 @@ public class LoadBalancerProvisioner {
     private final NodeRepository nodeRepository;
     private final CuratorDatabaseClient db;
     private final LoadBalancerService service;
+    private final BooleanFlag deactivateRouting;
 
     public LoadBalancerProvisioner(NodeRepository nodeRepository, LoadBalancerService service) {
         this.nodeRepository = nodeRepository;
         this.db = nodeRepository.database();
         this.service = service;
+        this.deactivateRouting = PermanentFlags.DEACTIVATE_ROUTING.bindTo(nodeRepository.flagSource());
         // Read and write all load balancers to make sure they are stored in the latest version of the serialization format
         for (var id : db.readLoadBalancerIds()) {
             try (var lock = db.lock(id.application())) {
@@ -204,12 +209,20 @@ public class LoadBalancerProvisioner {
 
     /** Provision or reconfigure a load balancer instance, if necessary */
     private Optional<LoadBalancerInstance> provisionInstance(LoadBalancerId id, NodeList nodes, Optional<LoadBalancer> currentLoadBalancer) {
-        Set<Real> reals = realsOf(nodes);
+        boolean shouldDeactivateRouting = deactivateRouting.with(FetchVector.Dimension.APPLICATION_ID,
+                                                                 id.application().serializedForm())
+                                                           .value();
+        Set<Real> reals;
+        if (shouldDeactivateRouting) {
+            reals = Set.of();
+        } else {
+            reals = realsOf(nodes);
+        }
         if (hasReals(currentLoadBalancer, reals)) return currentLoadBalancer.get().instance();
         log.log(Level.INFO, () -> "Provisioning instance for " + id + ", targeting: " + reals);
         try {
             return Optional.of(service.create(new LoadBalancerSpec(id.application(), id.cluster(), reals),
-                                              allowEmptyReals(currentLoadBalancer)));
+                                              shouldDeactivateRouting || allowEmptyReals(currentLoadBalancer)));
         } catch (Exception e) {
             log.log(Level.WARNING, e, () -> "Could not (re)configure " + id + ", targeting: " +
                                             reals + ". The operation will be retried on next deployment");
@@ -237,7 +250,7 @@ public class LoadBalancerProvisioner {
 
     /** Returns real servers for given nodes */
     private Set<Real> realsOf(NodeList nodes) {
-        Set<Real> reals = new LinkedHashSet<Real>();
+        Set<Real> reals = new LinkedHashSet<>();
         for (var node : nodes) {
             for (var ip : reachableIpAddresses(node)) {
                 reals.add(new Real(HostName.from(node.hostname()), ip));
diff --git a/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisionerTest.java b/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisionerTest.java
index b1f2efaef02..614817bce84 100644
--- a/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisionerTest.java
+++ b/node-repository/src/test/java/com/yahoo/vespa/hosted/provision/provisioning/LoadBalancerProvisionerTest.java
@@ -13,6 +13,7 @@ import com.yahoo.config.provision.NodeType;
 import com.yahoo.config.provision.exception.LoadBalancerServiceException;
 import com.yahoo.transaction.NestedTransaction;
 import com.yahoo.vespa.flags.InMemoryFlagSource;
+import com.yahoo.vespa.flags.PermanentFlags;
 import com.yahoo.vespa.hosted.provision.Node;
 import com.yahoo.vespa.hosted.provision.NodeList;
 import com.yahoo.vespa.hosted.provision.lb.LoadBalancer;
@@ -160,6 +161,18 @@ public class LoadBalancerProvisionerTest {
         tester.activate(app1, prepare(app1,
                                       clusterRequest(ClusterSpec.Type.container, containerCluster1),
                                       clusterRequest(ClusterSpec.Type.content, contentCluster)));
+
+        // Routing is disabled through feature flag. Reals are removed on next deployment
+        tester.loadBalancerService().throwOnCreate(false);
+        flagSource.withBooleanFlag(PermanentFlags.DEACTIVATE_ROUTING.id(), true);
+        tester.activate(app1, prepare(app1,
+                                      clusterRequest(ClusterSpec.Type.container, containerCluster1),
+                                      clusterRequest(ClusterSpec.Type.content, contentCluster)));
+        List<LoadBalancer> activeLoadBalancers = lbApp1.get().stream()
+                                                       .filter(lb -> lb.state() == LoadBalancer.State.active)
+                                                       .collect(Collectors.toList());
+        assertEquals(1, activeLoadBalancers.size());
+        assertEquals(Set.of(), activeLoadBalancers.get(0).instance().get().reals());
     }
 
     @Test