From d2bea3023fc9e7a2f43ed700f9b16f2de9f577f9 Mon Sep 17 00:00:00 2001
From: Larry Safran <lsafran@google.com>
Date: Wed, 12 Feb 2025 15:16:14 -0800
Subject: [PATCH 1/2] don't process resourceDoesNotExist for watchers that have
 been cancelled.

---
 .../java/io/grpc/xds/XdsDependencyManager.java   | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/xds/src/main/java/io/grpc/xds/XdsDependencyManager.java b/xds/src/main/java/io/grpc/xds/XdsDependencyManager.java
index 4adfebfe74d..7eff0c549e2 100644
--- a/xds/src/main/java/io/grpc/xds/XdsDependencyManager.java
+++ b/xds/src/main/java/io/grpc/xds/XdsDependencyManager.java
@@ -149,6 +149,7 @@ private <T extends ResourceUpdate> void cancelWatcher(XdsWatcherBase<T> watcher)
       throwIfParentContextsNotEmpty(watcher);
     }
 
+    watcher.cancelled = true;
     XdsResourceType<T> type = watcher.type;
     String resourceName = watcher.resourceName;
 
@@ -597,6 +598,8 @@ private abstract static class XdsWatcherBase<T extends ResourceUpdate>
       implements ResourceWatcher<T> {
     private final XdsResourceType<T> type;
     private final String resourceName;
+    boolean cancelled;
+
     @Nullable
     private StatusOr<T> data;
 
@@ -693,6 +696,10 @@ public void onError(Status error) {
 
     @Override
     public void onResourceDoesNotExist(String resourceName) {
+      if (cancelled) {
+        return;
+      }
+
       handleDoesNotExist(resourceName);
       xdsConfigWatcher.onResourceDoesNotExist(toContextString());
     }
@@ -752,6 +759,9 @@ public void onError(Status error) {
 
     @Override
     public void onResourceDoesNotExist(String resourceName) {
+      if (cancelled) {
+        return;
+      }
       handleDoesNotExist(checkNotNull(resourceName, "resourceName"));
       xdsConfigWatcher.onResourceDoesNotExist(toContextString());
     }
@@ -836,6 +846,9 @@ public void onChanged(XdsClusterResource.CdsUpdate update) {
 
     @Override
     public void onResourceDoesNotExist(String resourceName) {
+      if (cancelled) {
+        return;
+      }
       handleDoesNotExist(checkNotNull(resourceName, "resourceName"));
       maybePublishConfig();
     }
@@ -857,6 +870,9 @@ public void onChanged(XdsEndpointResource.EdsUpdate update) {
 
     @Override
     public void onResourceDoesNotExist(String resourceName) {
+      if (cancelled) {
+        return;
+      }
       handleDoesNotExist(checkNotNull(resourceName, "resourceName"));
       maybePublishConfig();
     }

From c871e58aa1ee8e0ee78fea184388fc7b6d867092 Mon Sep 17 00:00:00 2001
From: Larry Safran <lsafran@google.com>
Date: Thu, 13 Feb 2025 15:35:39 -0800
Subject: [PATCH 2/2] Change test to use an ArgumentMatcher instead of
 expecting that only the final result will be sent since depending on timing
 there may be configs sent for clusters being removed with their entries as
 errors.

---
 .../io/grpc/xds/XdsDependencyManagerTest.java | 24 ++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/xds/src/test/java/io/grpc/xds/XdsDependencyManagerTest.java b/xds/src/test/java/io/grpc/xds/XdsDependencyManagerTest.java
index c4b7c6c8ace..f94a94a9446 100644
--- a/xds/src/test/java/io/grpc/xds/XdsDependencyManagerTest.java
+++ b/xds/src/test/java/io/grpc/xds/XdsDependencyManagerTest.java
@@ -88,6 +88,7 @@
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
 import org.mockito.ArgumentCaptor;
+import org.mockito.ArgumentMatcher;
 import org.mockito.ArgumentMatchers;
 import org.mockito.Captor;
 import org.mockito.InOrder;
@@ -696,9 +697,9 @@ public void testChangeAggCluster() {
     controlPlaneService.setXdsConfig(ADS_TYPE_URL_EDS, edsMap);
 
     // Verify that the config is updated as expected
-    inOrder.verify(xdsConfigWatcher, timeout(1000)).onUpdate(xdsConfigCaptor.capture());
-    XdsConfig config = xdsConfigCaptor.getValue();
-    assertThat(config.getClusters().keySet()).containsExactly("root", "clusterA21", "clusterA22");
+    ClusterNameMatcher nameMatcher
+        = new ClusterNameMatcher(Arrays.asList("root", "clusterA21", "clusterA22"));
+    inOrder.verify(xdsConfigWatcher, timeout(1000)).onUpdate(argThat(nameMatcher));
   }
 
   private Listener buildInlineClientListener(String rdsName, String clusterName) {
@@ -789,4 +790,21 @@ void deliverLdsUpdate(long httpMaxStreamDurationNano,
       });
     }
   }
+
+  static class ClusterNameMatcher implements ArgumentMatcher<XdsConfig> {
+    private final List<String> expectedNames;
+
+    ClusterNameMatcher(List<String> expectedNames) {
+      this.expectedNames = expectedNames;
+    }
+
+    @Override
+    public boolean matches(XdsConfig xdsConfig) {
+      if (xdsConfig == null || xdsConfig.getClusters() == null) {
+        return false;
+      }
+      return xdsConfig.getClusters().size() == expectedNames.size()
+          && xdsConfig.getClusters().keySet().containsAll(expectedNames);
+    }
+  }
 }