delta-xds: fix wildcard resource versions

docs/root/version_history/current.rst

@@ -68,6 +68,7 @@ Bug Fixes
 * upstream: cluster slow start config add ``min_weight_percent`` field to avoid too big EDF deadline which cause slow start endpoints receiving no traffic, default 10%. This fix is releted to `issue#19526 <https://github.com/envoyproxy/envoy/issues/19526>`_.
 * upstream: fix stack overflow when a cluster with large number of idle connections is removed.
 * xds: fix a crash that occurs when Envoy receives a discovery response without ``control_plane`` field.
+* xds: fix the wildcard resource versions that are sent upon reconnection when using delta-xds mode.
 * xray: fix the AWS X-Ray tracer extension to not sample the trace if ``sampled=`` keyword is not present in the header ``x-amzn-trace-id``.
 * xray: fix the AWS X-Ray tracer extension to annotate a child span with ``type=subsegment`` to correctly relate subsegments to a parent segment. Previously a subsegment would be treated as an independent segment.
 * xray: fix the AWS X-Ray tracer extension to reuse the trace ID already present in the header ``x-amzn-trace-id`` instead of creating a new one.

source/common/config/new_delta_subscription_state.cc

@@ -78,7 +78,7 @@ void NewDeltaSubscriptionState::updateSubscriptionInterest(
         // won't be a wildcard resource then. If r is Wildcard itself, then it never has a version
         // attached to it, so it will not be moved to ambiguous category.
         if (!it->second.isWaitingForServer()) {
-          ambiguous_resource_state_.insert({it->first, it->second.version()});
+          ambiguous_resource_state_.insert_or_assign(it->first, it->second.version());
         }
         requested_resource_state_.erase(it);
         actually_erased = true;
@@ -375,7 +375,7 @@ void NewDeltaSubscriptionState::addResourceStateFromServer(
     ASSERT(!ambiguous_resource_state_.contains(resource.name()));
   } else {
     // It is a resource that is a part of our wildcard request.
-    wildcard_resource_state_.insert({resource.name(), resource.version()});
+    wildcard_resource_state_.insert_or_assign(resource.name(), resource.version());
     // The resource could be ambiguous before, but now the ambiguity
     // is resolved.
     ambiguous_resource_state_.erase(resource.name());

source/common/config/xds_mux/delta_subscription_state.cc

@@ -61,7 +61,7 @@ void DeltaSubscriptionState::updateSubscriptionInterest(
         // won't be a wildcard resource then. If r is Wildcard itself, then it never has a version
         // attached to it, so it will not be moved to ambiguous category.
         if (!it->second.isWaitingForServer()) {
-          ambiguous_resource_state_.insert({it->first, it->second.version()});
+          ambiguous_resource_state_.insert_or_assign(it->first, it->second.version());
         }
         requested_resource_state_.erase(it);
         actually_erased = true;
@@ -317,7 +317,7 @@ void DeltaSubscriptionState::addResourceStateFromServer(
     ASSERT(!ambiguous_resource_state_.contains(resource.name()));
   } else {
     // It is a resource that is a part of our wildcard request.
-    wildcard_resource_state_.insert({resource.name(), resource.version()});
+    wildcard_resource_state_.insert_or_assign(resource.name(), resource.version());
     // The resource could be ambiguous before, but now the ambiguity
     // is resolved.
     ambiguous_resource_state_.erase(resource.name());

test/common/config/delta_subscription_state_test.cc

@@ -387,6 +387,30 @@ TEST_P(DeltaSubscriptionStateTestBlank, LegacyWildcardInitialRequests) {
   EXPECT_TRUE(req->resource_names_unsubscribe().empty());
 }
 
+// Validate that the resources versions are updated and sent upon reconnection.
+// Regression test of: https://github.com/envoyproxy/envoy/issues/20699
+TEST_P(DeltaSubscriptionStateTestBlank, ReconnectResourcesVersions) {
+  // Subscribe to foo and bar.
+  updateSubscriptionInterest({WildcardStr, "foo", "bar"}, {});
+  auto req = getNextRequestAckless();
+  EXPECT_THAT(req->resource_names_subscribe(), UnorderedElementsAre(WildcardStr, "foo", "bar"));
+  EXPECT_TRUE(req->resource_names_unsubscribe().empty());
+  EXPECT_TRUE(req->initial_resource_versions().empty());
+  // Deliver foo, bar, and a wild with version 1.
+  deliverSimpleDiscoveryResponse({{"foo", "1"}, {"bar", "1"}, {"wild", "1"}}, {}, "d1");
+
+  // Update the versions of foo and wild to 2.
+  deliverSimpleDiscoveryResponse({{"foo", "2"}, {"wild", "2"}}, {}, "d2");
+
+  // Reconnect, and end validate the initial resources versions.
+  markStreamFresh();
+  req = getNextRequestAckless();
+  EXPECT_THAT(req->resource_names_subscribe(), UnorderedElementsAre(WildcardStr, "foo", "bar"));
+  EXPECT_TRUE(req->resource_names_unsubscribe().empty());
+  EXPECT_THAT(req->initial_resource_versions(),
+              UnorderedElementsAre(Pair("foo", "2"), Pair("bar", "1"), Pair("wild", "2")));
+}
+
 // Check that ambiguous resources may also receive a heartbeat message.
 TEST_P(DeltaSubscriptionStateTestBlank, AmbiguousResourceTTL) {
   Event::SimulatedTimeSystem time_system;