Fix tests and some underlying bugs

util/src/main/java/io/grpc/util/OutlierDetectionLoadBalancer.java

@@ -47,6 +47,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Random;
 import java.util.Set;
 import java.util.concurrent.ScheduledExecutorService;
@@ -1062,6 +1063,25 @@ public static class SuccessRateEjection {
         this.requestVolume = requestVolume;
       }
 
+      @Override
+      public int hashCode() {
+        return Objects.hash(stdevFactor, enforcementPercentage, minimumHosts, requestVolume);
+      }
+
+      @Override
+      public boolean equals(Object obj) {
+        if (this == obj) {
+          return true;
+        }
+        if (! (obj instanceof SuccessRateEjection)) {
+          return false;
+        }
+        return Objects.equals(stdevFactor, ((SuccessRateEjection) obj).stdevFactor)
+            && Objects.equals(enforcementPercentage, ((SuccessRateEjection) obj).enforcementPercentage)
+            && Objects.equals(minimumHosts, ((SuccessRateEjection) obj).minimumHosts)
+            && Objects.equals(requestVolume, ((SuccessRateEjection) obj).requestVolume);
+      }
+
       /** Builds new instances of {@link SuccessRateEjection}. */
       public static final class Builder {
 

xds/src/main/java/io/grpc/xds/CdsLoadBalancer2.java

@@ -239,6 +239,16 @@ public Status acceptResolvedAddresses(ResolvedAddresses resolvedAddresses) {
     }
 
     logger.log(XdsLogLevel.DEBUG, "Received resolution result: {0}", resolvedAddresses);
+    if (rootCdsLbState != null && this.resolvedAddresses != null
+        && rootClusterName.equals(rootCdsLbState.root.name)
+        && this.resolvedAddresses.equals(resolvedAddresses)) {
+      return Status.OK; // no changes
+    }
+
+    if (rootCdsLbState != null) {
+      rootCdsLbState.shutdown();
+    }
+
     this.resolvedAddresses = resolvedAddresses;
     rootCdsLbState =
         new CdsLbState(rootClusterName, xdsConfig.getClusters(), rootClusterName);
@@ -376,7 +386,7 @@ private void handleEndpointResourceUpdate() {
       if (childLb == null) {
         childLb = lbRegistry.getProvider(PRIORITY_POLICY_NAME).newLoadBalancer(helper);
       }
-      childLb.handleResolvedAddresses(
+      childLb.acceptResolvedAddresses(
           resolvedAddresses.toBuilder()
               .setLoadBalancingPolicyConfig(childConfig)
               .setAddresses(Collections.unmodifiableList(addresses))
@@ -805,7 +815,7 @@ private CdsLbState(String rootCluster,
                        String rootName) {
       root = new ClusterStateDetails(rootName, clusterConfigs.get(rootName));
       clusterStates.put(rootCluster, root);
-      initializeChildren(clusterConfigs, root);
+      initializeChildren(clusterConfigs, rootName);
     }
 
     private void start() {
@@ -820,18 +830,13 @@ private void shutdown() {
       }
     }
 
-    // If doesn't have children is a no-op
-    private void initializeChildren(ImmutableMap<String,
-        StatusOr<XdsClusterConfig>> clusterConfigs, ClusterStateDetails curRoot) {
-      if (curRoot.result == null) {
-        return;
-      }
-      ImmutableList<String> childNames = curRoot.result.prioritizedClusterNames();
-      if (childNames == null) {
-        return;
-      }
+    private void initializeChildren(
+        ImmutableMap<String, StatusOr<XdsClusterConfig>> clusterConfigs, String rootName) {
+      for (String clusterName : clusterConfigs.keySet()) {
+        if (clusterName.equals(rootName)) {
+          continue;
+        }
 
-      for (String clusterName : childNames) {
         StatusOr<XdsClusterConfig> configStatusOr = clusterConfigs.get(clusterName);
         if (configStatusOr == null) {
           logger.log(XdsLogLevel.DEBUG, "Child cluster %s of %s has no matching config",
@@ -843,7 +848,6 @@ private void initializeChildren(ImmutableMap<String,
           clusterStateDetails = new ClusterStateDetails(clusterName, configStatusOr);
           clusterStates.put(clusterName, clusterStateDetails);
         }
-        initializeChildren(clusterConfigs, clusterStateDetails);
       }
     }
 

xds/src/main/java/io/grpc/xds/XdsClusterResource.java

@@ -643,6 +643,25 @@ private static Builder newBuilder(String clusterName) {
           .parsedMetadata(ImmutableMap.of());
     }
 
+    Builder toBuilder() {
+      return new AutoValue_XdsClusterResource_CdsUpdate.Builder()
+          .choiceCount(choiceCount())
+          .clusterName(clusterName())
+          .clusterType(clusterType())
+          .dnsHostName(dnsHostName())
+          .edsServiceName(edsServiceName())
+          .lrsServerInfo(lrsServerInfo())
+          .maxConcurrentRequests(maxConcurrentRequests())
+          .maxRingSize(maxRingSize())
+          .minRingSize(minRingSize())
+          .lbPolicyConfig(lbPolicyConfig())
+          .upstreamTlsContext(upstreamTlsContext())
+          .prioritizedClusterNames(prioritizedClusterNames())
+          .outlierDetection(outlierDetection())
+          .filterMetadata(filterMetadata())
+          .parsedMetadata(parsedMetadata());
+    }
+
     static Builder forAggregate(String clusterName, List<String> prioritizedClusterNames) {
       checkNotNull(prioritizedClusterNames, "prioritizedClusterNames");
       return newBuilder(clusterName)

xds/src/main/java/io/grpc/xds/XdsConfig.java

@@ -29,6 +29,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 
 /**
  * Represents the xDS configuration tree for a specified Listener.
@@ -206,9 +207,9 @@ public String toString() {
 
     // The list of leaf clusters for an aggregate cluster.
     static final class AggregateConfig implements ClusterChild {
-      private final List<String> leafNames;
+      private final Set<String> leafNames;
 
-      public AggregateConfig(List<String> leafNames) {
+      public AggregateConfig(Set<String> leafNames) {
         this.leafNames = checkNotNull(leafNames, "leafNames");
       }
 

xds/src/main/java/io/grpc/xds/XdsDependencyManager.java

@@ -383,6 +383,7 @@ XdsConfig buildConfig() {
         cdsWatchers.values().stream()
             .filter(XdsDependencyManager::isTopLevelCluster)
             .map(XdsWatcherBase::resourceName)
+            .distinct()
             .collect(Collectors.toList());
 
     // Flatten multi-level aggregates into lists of leaf clusters
@@ -441,7 +442,7 @@ private static EndpointConfig buildEndpointConfig(CdsWatcher cdsWatcher,
     List<Endpoints.LbEndpoint> endpoints = new ArrayList<>();
     for (EquivalentAddressGroup eag : cdsWatcher.clusterState.addressGroupList) {
       // TODO: should this really be health and null hostname?
-      endpoints.add(Endpoints.LbEndpoint.create(eag, 1, true, null));
+      endpoints.add(Endpoints.LbEndpoint.create(eag, 1, true, ""));
     }
     LocalityLbEndpoints lbEndpoints = LocalityLbEndpoints.create(endpoints, 1, 0);
     localityLbEndpoints.put(locality, lbEndpoints);
@@ -470,9 +471,12 @@ private Set<String> addTopLevelClustersToBuilder(
       XdsConfig.XdsClusterConfig.ClusterChild child;
       switch (cdsUpdate.clusterType()) {
         case AGGREGATE:
-          List<String> leafNames = getLeafNames(cdsUpdate);
+          Set<String> leafNames = new HashSet<>();
+          addLeafNames(leafNames, cdsUpdate);
           child = new AggregateConfig(leafNames);
           leafClusterNames.addAll(leafNames);
+          cdsUpdate = cdsUpdate.toBuilder().prioritizedClusterNames(ImmutableList.copyOf(leafNames))
+              .build();
           break;
         case EDS:
           EdsWatcher edsWatcher = (EdsWatcher) edsWatchers.get(cdsUpdate.edsServiceName());
@@ -503,23 +507,24 @@ private Set<String> addTopLevelClustersToBuilder(
     return leafClusterNames;
   }
 
-  private List<String> getLeafNames(XdsClusterResource.CdsUpdate cdsUpdate) {
-    List<String> childNames = new ArrayList<>();
+  private void addLeafNames(Set<String> leafNames, XdsClusterResource.CdsUpdate cdsUpdate) {
+    Set<String> childNames = new HashSet<>();
 
     for (String cluster : cdsUpdate.prioritizedClusterNames()) {
+      if (leafNames.contains(cluster)) {
+        continue;
+      }
       StatusOr<XdsClusterResource.CdsUpdate> data = getCluster(cluster).getData();
       if (data == null || !data.hasValue() || data.getValue() == null) {
         childNames.add(cluster);
         continue;
       }
       if (data.getValue().clusterType() == ClusterType.AGGREGATE) {
-        childNames.addAll(getLeafNames(data.getValue()));
+        addLeafNames(leafNames, data.getValue());
       } else {
-        childNames.add(cluster);
+        leafNames.add(cluster);
       }
     }
-
-    return childNames;
   }
 
   private static boolean isTopLevelCluster(XdsWatcherBase<?> cdsWatcher) {