connect: remove support for Envoy 1.15

.circleci/config.yml

@@ -792,14 +792,14 @@ jobs:
           command: make test-coverage-ci
       - run: *notify-slack-failure
 
-  envoy-integration-test-1_15_5: &ENVOY_TESTS
+  envoy-integration-test-1_16_5: &ENVOY_TESTS
     docker:
       # We only really need bash and docker-compose which is installed on all
       # Circle images but pick Go since we have to pick one of them.
       - image: *GOLANG_IMAGE
     parallelism: 2
     environment:
-      ENVOY_VERSION: "1.15.5"
+      ENVOY_VERSION: "1.16.5"
     steps: &ENVOY_INTEGRATION_TEST_STEPS
       - checkout
       # Get go binary from workspace
@@ -832,17 +832,6 @@ jobs:
           path: *TEST_RESULTS_DIR
       - run: *notify-slack-failure
 
-  envoy-integration-test-1_15_5-v2compat:
-    <<: *ENVOY_TESTS
-    environment:
-      ENVOY_VERSION: "1.15.5"
-      TEST_V2_XDS: "1"
-
-  envoy-integration-test-1_16_5:
-    <<: *ENVOY_TESTS
-    environment:
-      ENVOY_VERSION: "1.16.5"
-
   envoy-integration-test-1_16_5-v2compat:
     <<: *ENVOY_TESTS
     environment:
@@ -1104,12 +1093,6 @@ workflows:
       - nomad-integration-0_8:
           requires:
             - dev-build
-      - envoy-integration-test-1_15_5:
-          requires:
-            - dev-build
-      - envoy-integration-test-1_15_5-v2compat:
-          requires:
-            - dev-build
       - envoy-integration-test-1_16_5:
           requires:
             - dev-build

agent/xds/clusters.go

@@ -38,53 +38,24 @@ func (s *ResourceGenerator) clustersFromSnapshot(cfgSnap *proxycfg.ConfigSnapsho
 		if err != nil {
 			return nil, err
 		}
-		return s.maybeInjectStubClusterForGateways(res)
+		return res, nil
 	case structs.ServiceKindMeshGateway:
 		res, err := s.clustersFromSnapshotMeshGateway(cfgSnap)
 		if err != nil {
 			return nil, err
 		}
-		return s.maybeInjectStubClusterForGateways(res)
+		return res, nil
 	case structs.ServiceKindIngressGateway:
 		res, err := s.clustersFromSnapshotIngressGateway(cfgSnap)
 		if err != nil {
 			return nil, err
 		}
-		return s.maybeInjectStubClusterForGateways(res)
+		return res, nil
 	default:
 		return nil, fmt.Errorf("Invalid service kind: %v", cfgSnap.Kind)
 	}
 }
 
-func (s *ResourceGenerator) maybeInjectStubClusterForGateways(resources []proto.Message) ([]proto.Message, error) {
-	switch {
-	case !s.IncrementalXDS:
-		return resources, nil
-	case !s.ProxyFeatures.GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS:
-		return resources, nil
-	case len(resources) > 0:
-		return resources, nil
-	}
-
-	// For more justification for this hacky fix, check the comments associated
-	// with s.ProxyFeatures.GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS
-
-	const stubName = "consul-stub-cluster-working-around-envoy-bug-ignore"
-	return []proto.Message{
-		&envoy_cluster_v3.Cluster{
-			Name:                 stubName,
-			ConnectTimeout:       ptypes.DurationProto(5 * time.Second),
-			ClusterDiscoveryType: &envoy_cluster_v3.Cluster_Type{Type: envoy_cluster_v3.Cluster_STATIC},
-			LoadAssignment: &envoy_endpoint_v3.ClusterLoadAssignment{
-				ClusterName: stubName,
-				Endpoints: []*envoy_endpoint_v3.LocalityLbEndpoints{
-					{LbEndpoints: []*envoy_endpoint_v3.LbEndpoint{}},
-				},
-			},
-		},
-	}, nil
-}
-
 // clustersFromSnapshot returns the xDS API representation of the "clusters"
 // (upstreams) in the snapshot.
 func (s *ResourceGenerator) clustersFromSnapshotConnectProxy(cfgSnap *proxycfg.ConfigSnapshot) ([]proto.Message, error) {

agent/xds/delta.go

@@ -310,12 +310,6 @@ func (s *Server) processDelta(stream ADSDeltaStream, reqCh <-chan *envoy_discove
 				}
 				if sent {
 					sentType[op.TypeUrl] = struct{}{}
-					if generator.ProxyFeatures.IncrementalXDSUpdatesMustBeSerial {
-						// For more justification for this hacky fix, check the
-						// comments associated with
-						// generator.ProxyFeatures.IncrementalXDSUpdatesMustBeSerial
-						break
-					}
 				}
 			}
 		}

agent/xds/delta_test.go

@@ -1228,7 +1228,7 @@ func TestServer_DeltaAggregatedResources_v3_IngressEmptyResponse(t *testing.T) {
 	// REQ: clusters
 	envoy.SendDeltaReq(t, ClusterType, nil)
 
-	// RESP: clustesr
+	// RESP: cluster
 	assertDeltaResponseSent(t, envoy.deltaStream.sendCh, &envoy_discovery_v3.DeltaDiscoveryResponse{
 		TypeUrl: ClusterType,
 		Nonce:   hexString(1),

agent/xds/envoy_versioning.go

@@ -11,10 +11,10 @@ import (
 var (
 	// minSupportedVersion is the oldest mainline version we support. This should always be
 	// the zero'th point release of the last element of proxysupport.EnvoyVersions.
-	minSupportedVersion = version.Must(version.NewVersion("1.15.0"))
+	minSupportedVersion = version.Must(version.NewVersion("1.16.0"))
 
-	minVersionAllowingEmptyGatewayClustersWithIncrementalXDS = version.Must(version.NewVersion("1.16.0"))
-	minVersionAllowingMultipleIncrementalXDSChanges          = version.Must(version.NewVersion("1.16.0"))
+	// add min version constraints for associated feature flags when necessary, for example:
+	// minVersionAllowingEmptyGatewayClustersWithIncrementalXDS = version.Must(version.NewVersion("1.16.0"))
 
 	specificUnsupportedVersions = []unsupportedVersion{}
 )
@@ -27,24 +27,15 @@ type unsupportedVersion struct {
 
 type supportedProxyFeatures struct {
 	// add version dependent feature flags here
-
-	// GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS is needed to paper
-	// over some weird envoy behavior.
 	//
-	// For some reason Envoy versions prior to 1.16.0 when sent an empty CDS
-	// list via the incremental xDS protocol will correctly ack the message and
-	// just never request LDS resources.
-	GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS bool
-
-	// IncrementalXDSUpdatesMustBeSerial is needed to avoid an envoy crash.
+	// For example, we previously had flags for Envoy < 1.16 called:
 	//
-	// Versions of Envoy prior to 1.16.0 could crash if multiple in-flight
-	// changes to resources were happening during incremental xDS. To prevent
-	// that we force serial updates on those older versions.
+	// GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS
+	// IncrementalXDSUpdatesMustBeSerial
 	//
-	// issue: https://github.com/envoyproxy/envoy/issues/11877
-	// PR:    https://github.com/envoyproxy/envoy/pull/12069
-	IncrementalXDSUpdatesMustBeSerial bool
+	// Which then manifested in the code for checks with this struct populated.
+	// By dropping support for 1.15, we no longer have any special flags here
+	// but leaving this flagging functionality for future one-offs.
 }
 
 func determineSupportedProxyFeatures(node *envoy_core_v3.Node) (supportedProxyFeatures, error) {
@@ -82,13 +73,12 @@ func determineSupportedProxyFeaturesFromVersion(version *version.Version) (suppo
 
 	sf := supportedProxyFeatures{}
 
-	if version.LessThan(minVersionAllowingEmptyGatewayClustersWithIncrementalXDS) {
-		sf.GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS = true
-	}
-
-	if version.LessThan(minVersionAllowingMultipleIncrementalXDSChanges) {
-		sf.IncrementalXDSUpdatesMustBeSerial = true
-	}
+	// add version contraints to poipulate feature flags here when necessary, for example:
+	/*
+		if version.LessThan(minVersionAllowingEmptyGatewayClustersWithIncrementalXDS) {
+			sf.GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS = true
+		}
+	*/
 
 	return sf, nil
 }

agent/xds/envoy_versioning_test.go

@@ -109,14 +109,7 @@ func TestDetermineSupportedProxyFeaturesFromString(t *testing.T) {
 	}
 
 	// Insert a bunch of valid versions.
-	for _, v := range []string{
-		"1.15.0", "1.15.1", "1.15.2", "1.15.3", "1.15.4", "1.15.5",
-	} {
-		cases[v] = testcase{expect: supportedProxyFeatures{
-			GatewaysNeedStubClusterWhenEmptyWithIncrementalXDS: true,
-			IncrementalXDSUpdatesMustBeSerial:                  true,
-		}}
-	}
+	// Populate feature flags here when appropriate. See consul 1.10.x for reference.
 	for _, v := range []string{
 		"1.16.0", "1.16.1", "1.16.2", "1.16.3", "1.16.4", "1.16.5",
 		"1.17.0", "1.17.1", "1.17.2", "1.17.3", "1.17.4",

agent/xds/proxysupport/proxysupport.go

@@ -11,10 +11,8 @@ var EnvoyVersions = []string{
 	"1.18.4",
 	"1.17.4",
 	"1.16.5",
-	"1.15.5",
 }
 
 var EnvoyVersionsV2 = []string{
 	"1.16.5",
-	"1.15.5",
 }