proxycfg: remove dependency on `cache.UpdateEvent` (#13144)

OSS portion of enterprise PR 1857.

This removes (most) references to the `cache.UpdateEvent` type in the
`proxycfg` package.

As we're going to be direct usage of the agent cache with interfaces that
can be satisfied by alternative server-local datasources, it doesn't make
sense to depend on this type everywhere anymore (particularly on the
`state.ch` channel).

We also plan to extract `proxycfg` out of Consul into a shared library in
the future, which would require removing this dependency.

Aside from a fairly rote find-and-replace, the main change is that the
`cache.Cache` and `health.Client` types now accept a callback function
parameter, rather than a `chan<- cache.UpdateEvents`. This allows us to
do the type conversion without running another goroutine.

agent/agent.go

@@ -626,8 +626,8 @@ func (a *Agent) Start(ctx context.Context) error {
 
 	// Start the proxy config manager.
 	a.proxyConfig, err = proxycfg.NewManager(proxycfg.ManagerConfig{
-		Cache:  a.cache,
+		Cache:  &proxycfg.CacheWrapper{Cache: a.cache},
-		Health: a.rpcClientHealth,
+		Health: &proxycfg.HealthWrapper{Health: a.rpcClientHealth},
 		Logger: a.logger.Named(logging.ProxyConfig),
 		State:  a.State,
 		Tokens: a.baseDeps.Tokens,

agent/cache/watch.go

@@ -23,6 +23,9 @@ type UpdateEvent struct {
 	Err           error
 }
 
+// Callback is the function type accepted by NotifyCallback.
+type Callback func(ctx context.Context, event UpdateEvent)
+
 // Notify registers a desire to be updated about changes to a cache result.
 //
 // It is a helper that abstracts code from performing their own "blocking" query
@@ -56,6 +59,24 @@ func (c *Cache) Notify(
 	r Request,
 	correlationID string,
 	ch chan<- UpdateEvent,
+) error {
+	return c.NotifyCallback(ctx, t, r, correlationID, func(ctx context.Context, event UpdateEvent) {
+		select {
+		case ch <- event:
+		case <-ctx.Done():
+		}
+	})
+}
+
+// NotifyCallback allows you to receive notifications about changes to a cache
+// result in the same way as Notify, but accepts a callback function instead of
+// a channel.
+func (c *Cache) NotifyCallback(
+	ctx context.Context,
+	t string,
+	r Request,
+	correlationID string,
+	cb Callback,
 ) error {
 	c.typesLock.RLock()
 	tEntry, ok := c.types[t]
@@ -65,7 +86,7 @@ func (c *Cache) Notify(
 	}
 
 	if tEntry.Opts.SupportsBlocking {
-		go c.notifyBlockingQuery(ctx, newGetOptions(tEntry, r), correlationID, ch)
+		go c.notifyBlockingQuery(ctx, newGetOptions(tEntry, r), correlationID, cb)
 		return nil
 	}
 
@@ -73,11 +94,11 @@ func (c *Cache) Notify(
 	if info.MaxAge == 0 {
 		return fmt.Errorf("Cannot use Notify for polling cache types without specifying the MaxAge")
 	}
-	go c.notifyPollingQuery(ctx, newGetOptions(tEntry, r), correlationID, ch)
+	go c.notifyPollingQuery(ctx, newGetOptions(tEntry, r), correlationID, cb)
 	return nil
 }
 
-func (c *Cache) notifyBlockingQuery(ctx context.Context, r getOptions, correlationID string, ch chan<- UpdateEvent) {
+func (c *Cache) notifyBlockingQuery(ctx context.Context, r getOptions, correlationID string, cb Callback) {
 	// Always start at 0 index to deliver the initial (possibly currently cached
 	// value).
 	index := uint64(0)
@@ -101,12 +122,7 @@ func (c *Cache) notifyBlockingQuery(ctx context.Context, r getOptions, correlati
 		// Check the index of the value returned in the cache entry to be sure it
 		// changed
 		if index == 0 || index < meta.Index {
-			u := UpdateEvent{correlationID, res, meta, err}
+			cb(ctx, UpdateEvent{correlationID, res, meta, err})
-			select {
-			case ch <- u:
-			case <-ctx.Done():
-				return
-			}
 
 			// Update index for next request
 			index = meta.Index
@@ -143,7 +159,7 @@ func (c *Cache) notifyBlockingQuery(ctx context.Context, r getOptions, correlati
 	}
 }
 
-func (c *Cache) notifyPollingQuery(ctx context.Context, r getOptions, correlationID string, ch chan<- UpdateEvent) {
+func (c *Cache) notifyPollingQuery(ctx context.Context, r getOptions, correlationID string, cb Callback) {
 	index := uint64(0)
 	failures := uint(0)
 
@@ -166,12 +182,7 @@ func (c *Cache) notifyPollingQuery(ctx context.Context, r getOptions, correlatio
 
 		// Check for a change in the value or an index change
 		if index < meta.Index || !reflect.DeepEqual(lastValue, res) {
-			u := UpdateEvent{correlationID, res, meta, err}
+			cb(ctx, UpdateEvent{correlationID, res, meta, err})
-			select {
-			case ch <- u:
-			case <-ctx.Done():
-				return
-			}
 
 			// Update index and lastValue
 			lastValue = res

agent/proxycfg/connect_proxy.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/hashicorp/consul/agent/cache"
 	cachetype "github.com/hashicorp/consul/agent/cache-types"
 	"github.com/hashicorp/consul/agent/configentry"
 	"github.com/hashicorp/consul/agent/consul/discoverychain"
@@ -220,7 +219,7 @@ func (s *handlerConnectProxy) initialize(ctx context.Context) (ConfigSnapshot, e
 	return snap, nil
 }
 
-func (s *handlerConnectProxy) handleUpdate(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error {
+func (s *handlerConnectProxy) handleUpdate(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error {
 	if u.Err != nil {
 		return fmt.Errorf("error filling agent cache: %v", u.Err)
 	}

agent/proxycfg/glue.go

@@ -0,0 +1,60 @@
+// TODO(agentless): these glue types belong in the agent package, but moving
+// them is a little tricky because the proxycfg tests use them. It should be
+// easier to break apart once we no longer depend on cache.Notify directly.
+package proxycfg
+
+import (
+	"context"
+
+	"github.com/hashicorp/consul/agent/cache"
+	"github.com/hashicorp/consul/agent/rpcclient/health"
+	"github.com/hashicorp/consul/agent/structs"
+)
+
+// HealthWrapper wraps health.Client so that the rest of the proxycfg package
+// doesn't need to reference cache.UpdateEvent (it will be extracted into a
+// shared library in the future).
+type HealthWrapper struct {
+	Health *health.Client
+}
+
+func (w *HealthWrapper) Notify(
+	ctx context.Context,
+	req structs.ServiceSpecificRequest,
+	correlationID string,
+	ch chan<- UpdateEvent,
+) error {
+	return w.Health.Notify(ctx, req, correlationID, dispatchCacheUpdate(ctx, ch))
+}
+
+// CacheWrapper wraps cache.Cache so that the rest of the proxycfg package
+// doesn't need to reference cache.UpdateEvent (it will be extracted into a
+// shared library in the future).
+type CacheWrapper struct {
+	Cache *cache.Cache
+}
+
+func (w *CacheWrapper) Notify(
+	ctx context.Context,
+	t string,
+	req cache.Request,
+	correlationID string,
+	ch chan<- UpdateEvent,
+) error {
+	return w.Cache.NotifyCallback(ctx, t, req, correlationID, dispatchCacheUpdate(ctx, ch))
+}
+
+func dispatchCacheUpdate(ctx context.Context, ch chan<- UpdateEvent) cache.Callback {
+	return func(ctx context.Context, e cache.UpdateEvent) {
+		u := UpdateEvent{
+			CorrelationID: e.CorrelationID,
+			Result:        e.Result,
+			Err:           e.Err,
+		}
+
+		select {
+		case ch <- u:
+		case <-ctx.Done():
+		}
+	}
+}

agent/proxycfg/ingress_gateway.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/hashicorp/consul/agent/cache"
 	cachetype "github.com/hashicorp/consul/agent/cache-types"
 	"github.com/hashicorp/consul/agent/structs"
 )
@@ -70,7 +69,7 @@ func (s *handlerIngressGateway) initialize(ctx context.Context) (ConfigSnapshot,
 	return snap, nil
 }
 
-func (s *handlerIngressGateway) handleUpdate(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error {
+func (s *handlerIngressGateway) handleUpdate(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error {
 	if u.Err != nil {
 		return fmt.Errorf("error filling agent cache: %v", u.Err)
 	}

agent/proxycfg/manager.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/hashicorp/go-hclog"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/local"
 	"github.com/hashicorp/consul/agent/structs"
 	"github.com/hashicorp/consul/agent/token"
@@ -59,7 +58,7 @@ type Manager struct {
 type ManagerConfig struct {
 	// Cache is the agent's cache instance that can be used to retrieve, store and
 	// monitor state for the proxies.
-	Cache *cache.Cache
+	Cache CacheNotifier
 	// Health provides service health updates on a notification channel.
 	Health Health
 	// state is the agent's local state to be watched for new proxy registrations.

agent/proxycfg/manager_test.go

@@ -376,8 +376,8 @@ func testManager_BasicLifecycle(
 
 	// Create manager
 	m, err := NewManager(ManagerConfig{
-		Cache:  c,
+		Cache:  &CacheWrapper{c},
-		Health: &health.Client{Cache: c, CacheName: cachetype.HealthServicesName},
+		Health: &HealthWrapper{&health.Client{Cache: c, CacheName: cachetype.HealthServicesName}},
 		State:  state,
 		Source: source,
 		Logger: logger,
@@ -509,7 +509,7 @@ func TestManager_deliverLatest(t *testing.T) {
 	// None of these need to do anything to test this method just be valid
 	logger := testutil.Logger(t)
 	cfg := ManagerConfig{
-		Cache: cache.New(cache.Options{EntryFetchRate: rate.Inf, EntryFetchMaxBurst: 2}),
+		Cache: &CacheWrapper{cache.New(cache.Options{EntryFetchRate: rate.Inf, EntryFetchMaxBurst: 2})},
 		State: local.NewState(local.Config{}, logger, &token.Store{}),
 		Source: &structs.QuerySource{
 			Node:       "node1",
@@ -581,8 +581,8 @@ func TestManager_SyncState_DefaultToken(t *testing.T) {
 	state.TriggerSyncChanges = func() {}
 
 	m, err := NewManager(ManagerConfig{
-		Cache:  c,
+		Cache:  &CacheWrapper{c},
-		Health: &health.Client{Cache: c, CacheName: cachetype.HealthServicesName},
+		Health: &HealthWrapper{&health.Client{Cache: c, CacheName: cachetype.HealthServicesName}},
 		State:  state,
 		Tokens: tokens,
 		Source: &structs.QuerySource{Datacenter: "dc1"},
@@ -626,8 +626,8 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 	state.TriggerSyncChanges = func() {}
 
 	m, err := NewManager(ManagerConfig{
-		Cache:  c,
+		Cache:  &CacheWrapper{c},
-		Health: &health.Client{Cache: c, CacheName: cachetype.HealthServicesName},
+		Health: &HealthWrapper{&health.Client{Cache: c, CacheName: cachetype.HealthServicesName}},
 		State:  state,
 		Tokens: tokens,
 		Source: &structs.QuerySource{Datacenter: "dc1"},
@@ -673,7 +673,7 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 
 	// update the leaf certs
 	roots, issuedCert := TestCerts(t)
-	notifyCH <- cache.UpdateEvent{
+	notifyCH <- UpdateEvent{
 		CorrelationID: leafWatchID,
 		Result:        issuedCert,
 		Err:           nil,
@@ -688,7 +688,7 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 	}
 
 	// update the root certs
-	notifyCH <- cache.UpdateEvent{
+	notifyCH <- UpdateEvent{
 		CorrelationID: rootsWatchID,
 		Result:        roots,
 		Err:           nil,
@@ -704,7 +704,7 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 	}
 
 	// update the mesh config entry
-	notifyCH <- cache.UpdateEvent{
+	notifyCH <- UpdateEvent{
 		CorrelationID: meshConfigEntryID,
 		Result:        &structs.ConfigEntryResponse{},
 		Err:           nil,
@@ -723,7 +723,7 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 	readEvent <- true
 
 	// update the intentions
-	notifyCH <- cache.UpdateEvent{
+	notifyCH <- UpdateEvent{
 		CorrelationID: intentionsWatchID,
 		Result:        &structs.IndexedIntentionMatches{},
 		Err:           nil,
@@ -741,7 +741,7 @@ func TestManager_SyncState_No_Notify(t *testing.T) {
 	// send two snapshots back to back without reading them to overflow the snapshot channel and get to the default use case
 	for i := 0; i < 2; i++ {
 		time.Sleep(250 * time.Millisecond)
-		notifyCH <- cache.UpdateEvent{
+		notifyCH <- UpdateEvent{
 			CorrelationID: leafWatchID,
 			Result:        issuedCert,
 			Err:           nil,

agent/proxycfg/mesh_gateway.go

@@ -6,7 +6,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/hashicorp/consul/agent/cache"
 	cachetype "github.com/hashicorp/consul/agent/cache-types"
 	"github.com/hashicorp/consul/agent/structs"
 	"github.com/hashicorp/consul/logging"
@@ -119,7 +118,7 @@ func (s *handlerMeshGateway) initializeCrossDCWatches(ctx context.Context) error
 	return nil
 }
 
-func (s *handlerMeshGateway) handleUpdate(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error {
+func (s *handlerMeshGateway) handleUpdate(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error {
 	if u.Err != nil {
 		return fmt.Errorf("error filling agent cache: %v", u.Err)
 	}

agent/proxycfg/mesh_gateway_oss.go

@@ -7,14 +7,12 @@ import (
 	"context"
 
 	"github.com/hashicorp/go-hclog"
-
-	"github.com/hashicorp/consul/agent/cache"
 )
 
 func (s *handlerMeshGateway) initializeEntWatches(_ context.Context) error {
 	return nil
 }
 
-func (s *handlerMeshGateway) handleEntUpdate(_ hclog.Logger, _ context.Context, _ cache.UpdateEvent, _ *ConfigSnapshot) error {
+func (s *handlerMeshGateway) handleEntUpdate(_ hclog.Logger, _ context.Context, _ UpdateEvent, _ *ConfigSnapshot) error {
 	return nil
 }

agent/proxycfg/state.go

@@ -17,13 +17,21 @@ import (
 	"github.com/hashicorp/consul/logging"
 )
 
+// UpdateEvent contains new data for a resource we are subscribed to (e.g. an
+// agent cache entry).
+type UpdateEvent struct {
+	CorrelationID string
+	Result        interface{}
+	Err           error
+}
+
 type CacheNotifier interface {
 	Notify(ctx context.Context, t string, r cache.Request,
-		correlationID string, ch chan<- cache.UpdateEvent) error
+		correlationID string, ch chan<- UpdateEvent) error
 }
 
 type Health interface {
-	Notify(ctx context.Context, req structs.ServiceSpecificRequest, correlationID string, ch chan<- cache.UpdateEvent) error
+	Notify(ctx context.Context, req structs.ServiceSpecificRequest, correlationID string, ch chan<- UpdateEvent) error
 }
 
 const (
@@ -72,7 +80,7 @@ type state struct {
 	// in Watch.
 	cancel func()
 
-	ch     chan cache.UpdateEvent
+	ch     chan UpdateEvent
 	snapCh chan ConfigSnapshot
 	reqCh  chan chan *ConfigSnapshot
 }
@@ -153,7 +161,7 @@ func newState(ns *structs.NodeService, token string, config stateConfig) (*state
 	// conservative to handle larger numbers of upstreams correctly but gives
 	// some head room for normal operation to be non-blocking in most typical
 	// cases.
-	ch := make(chan cache.UpdateEvent, 10)
+	ch := make(chan UpdateEvent, 10)
 
 	s, err := newServiceInstanceFromNodeService(ns, token)
 	if err != nil {
@@ -175,7 +183,7 @@ func newState(ns *structs.NodeService, token string, config stateConfig) (*state
 	}, nil
 }
 
-func newKindHandler(config stateConfig, s serviceInstance, ch chan cache.UpdateEvent) (kindHandler, error) {
+func newKindHandler(config stateConfig, s serviceInstance, ch chan UpdateEvent) (kindHandler, error) {
 	var handler kindHandler
 	h := handlerState{stateConfig: config, serviceInstance: s, ch: ch}
 
@@ -228,7 +236,7 @@ func newServiceInstanceFromNodeService(ns *structs.NodeService, token string) (s
 
 type kindHandler interface {
 	initialize(ctx context.Context) (ConfigSnapshot, error)
-	handleUpdate(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error
+	handleUpdate(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error
 }
 
 // Watch initialized watches on all necessary cache data for the current proxy
@@ -261,7 +269,7 @@ func (s *state) Close() error {
 type handlerState struct {
 	stateConfig     // TODO: un-embed
 	serviceInstance // TODO: un-embed
-	ch              chan cache.UpdateEvent
+	ch              chan UpdateEvent
 }
 
 func newConfigSnapshotFromServiceInstance(s serviceInstance, config stateConfig) ConfigSnapshot {
@@ -450,7 +458,7 @@ func hostnameEndpoints(logger hclog.Logger, localKey GatewayKey, nodes structs.C
 
 type gatewayWatchOpts struct {
 	notifier   CacheNotifier
-	notifyCh   chan cache.UpdateEvent
+	notifyCh   chan UpdateEvent
 	source     structs.QuerySource
 	token      string
 	key        GatewayKey

agent/proxycfg/state_test.go

@@ -126,7 +126,7 @@ func TestStateChanged(t *testing.T) {
 type testCacheNotifierRequest struct {
 	cacheType string
 	request   cache.Request
-	ch        chan<- cache.UpdateEvent
+	cb        func(UpdateEvent)
 }
 
 type testCacheNotifier struct {
@@ -140,9 +140,23 @@ func newTestCacheNotifier() *testCacheNotifier {
 	}
 }
 
-func (cn *testCacheNotifier) Notify(ctx context.Context, t string, r cache.Request, correlationId string, ch chan<- cache.UpdateEvent) error {
+func (cn *testCacheNotifier) Notify(ctx context.Context, t string, r cache.Request, correlationId string, ch chan<- UpdateEvent) error {
 	cn.lock.Lock()
-	cn.notifiers[correlationId] = testCacheNotifierRequest{t, r, ch}
+	cn.notifiers[correlationId] = testCacheNotifierRequest{t, r, func(event UpdateEvent) { ch <- event }}
+	cn.lock.Unlock()
+	return nil
+}
+
+// NotifyCallback satisfies the health.CacheGetter interface.
+func (cn *testCacheNotifier) NotifyCallback(ctx context.Context, t string, r cache.Request, correlationId string, cb cache.Callback) error {
+	cn.lock.Lock()
+	cn.notifiers[correlationId] = testCacheNotifierRequest{t, r, func(event UpdateEvent) {
+		cb(ctx, cache.UpdateEvent{
+			CorrelationID: event.CorrelationID,
+			Result:        event.Result,
+			Err:           event.Err,
+		})
+	}}
 	cn.lock.Unlock()
 	return nil
 }
@@ -159,20 +173,16 @@ func (cn *testCacheNotifier) getNotifierRequest(t testing.TB, correlationId stri
 	return req
 }
 
-func (cn *testCacheNotifier) getChanForCorrelationId(t testing.TB, correlationId string) chan<- cache.UpdateEvent {
+func (cn *testCacheNotifier) sendNotification(t testing.TB, correlationId string, event UpdateEvent) {
 	req := cn.getNotifierRequest(t, correlationId)
-	require.NotNil(t, req.ch)
+	require.NotNil(t, req.cb)
-	return req.ch
+	req.cb(event)
-}
-
-func (cn *testCacheNotifier) sendNotification(t testing.TB, correlationId string, event cache.UpdateEvent) {
-	cn.getChanForCorrelationId(t, correlationId) <- event
 }
 
 func (cn *testCacheNotifier) verifyWatch(t testing.TB, correlationId string) (string, cache.Request) {
 	// t.Logf("Watches: %+v", cn.notifiers)
 	req := cn.getNotifierRequest(t, correlationId)
-	require.NotNil(t, req.ch)
+	require.NotNil(t, req.cb)
 	return req.cacheType, req.request
 }
 
@@ -348,7 +358,7 @@ func genVerifyConfigEntryWatch(expectedKind, expectedName, expectedDatacenter st
 	}
 }
 
-func ingressConfigWatchEvent(gwTLS bool, mixedTLS bool) cache.UpdateEvent {
+func ingressConfigWatchEvent(gwTLS bool, mixedTLS bool) UpdateEvent {
 	e := &structs.IngressGatewayConfigEntry{
 		TLS: structs.GatewayTLSConfig{
 			Enabled: gwTLS,
@@ -371,7 +381,7 @@ func ingressConfigWatchEvent(gwTLS bool, mixedTLS bool) cache.UpdateEvent {
 		}
 	}
 
-	return cache.UpdateEvent{
+	return UpdateEvent{
 		CorrelationID: gatewayConfigWatchID,
 		Result: &structs.ConfigEntryResponse{
 			Entry: e,
@@ -420,8 +430,8 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 	// TODO(peering): NewUpstreamIDFromServiceName should take a PeerName
 	extApiUID.Peer = "peer-a"
 
-	rootWatchEvent := func() cache.UpdateEvent {
+	rootWatchEvent := func() UpdateEvent {
-		return cache.UpdateEvent{
+		return UpdateEvent{
 			CorrelationID: rootsWatchID,
 			Result:        indexedRoots,
 			Err:           nil,
@@ -430,7 +440,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 
 	type verificationStage struct {
 		requiredWatches map[string]verifyWatchRequest
-		events          []cache.UpdateEvent
+		events          []UpdateEvent
 		verifySnapshot  func(t testing.TB, snap *ConfigSnapshot)
 	}
 
@@ -562,7 +572,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				}),
 			},
-			events: []cache.UpdateEvent{
+			events: []UpdateEvent{
 				rootWatchEvent(),
 				{
 					CorrelationID: leafWatchID,
@@ -752,7 +762,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 					},
 					verifySnapshot: func(t testing.TB, snap *ConfigSnapshot) {
@@ -768,7 +778,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: serviceListWatchID,
 							Result: &structs.IndexedServiceList{
@@ -807,7 +817,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						serviceListWatchID: genVerifyListServicesWatch("dc1"),
 						datacentersWatchID: verifyDatacentersWatch,
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: serviceListWatchID,
@@ -826,7 +836,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: serviceListWatchID,
 							Result: &structs.IndexedServiceList{
@@ -845,7 +855,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "mesh-gateway:dc4",
 							Result: &structs.IndexedNodesWithGateways{
@@ -889,7 +899,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: federationStateListGatewaysWatchID,
 							Result: &structs.DatacenterIndexedCheckServiceNodes{
@@ -958,7 +968,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: meshConfigEntryID,
@@ -971,7 +981,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						ingressConfigWatchEvent(false, false),
 					},
 					verifySnapshot: func(t testing.TB, snap *ConfigSnapshot) {
@@ -981,7 +991,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: gatewayServicesWatchID,
 							Result: &structs.IndexedGatewayServices{
@@ -1022,7 +1032,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						leafWatchID: genVerifyLeafWatch("ingress-gateway", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: leafWatchID,
 							Result:        issuedCert,
@@ -1044,7 +1054,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							Datacenter:           "dc1",
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "discovery-chain:" + apiUID.String(),
 							Result: &structs.DiscoveryChainResponse{
@@ -1062,7 +1072,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"upstream-target:api.default.default.dc1:" + apiUID.String(): genVerifyServiceWatch("api", "", "dc1", true),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "upstream-target:api.default.default.dc1:" + apiUID.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -1121,7 +1131,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						gatewayConfigWatchID:   genVerifyConfigEntryWatch(structs.IngressGateway, "ingress-gateway", "dc1"),
 						gatewayServicesWatchID: genVerifyGatewayServiceWatch("ingress-gateway", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: meshConfigEntryID,
@@ -1169,7 +1179,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							"*.ingress.dc1.alt.consul.",
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: gatewayServicesWatchID,
 							Result:        &structs.IndexedGatewayServices{},
@@ -1201,7 +1211,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						gatewayConfigWatchID:   genVerifyConfigEntryWatch(structs.IngressGateway, "ingress-gateway", "dc1"),
 						gatewayServicesWatchID: genVerifyGatewayServiceWatch("ingress-gateway", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: meshConfigEntryID,
@@ -1262,7 +1272,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							"*.ingress.dc1.alt.consul.",
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: gatewayServicesWatchID,
 							Result:        &structs.IndexedGatewayServices{},
@@ -1302,7 +1312,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: meshConfigEntryID,
@@ -1337,7 +1347,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						gatewayServicesWatchID: genVerifyServiceSpecificRequest(gatewayServicesWatchID,
 							"terminating-gateway", "", "dc1", false),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: meshConfigEntryID,
@@ -1365,7 +1375,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: gatewayServicesWatchID,
 							Result: &structs.IndexedGatewayServices{
@@ -1426,7 +1436,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"external-service:" + db.String(): genVerifyServiceWatch("db", "", "dc1", false),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "external-service:" + db.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -1471,7 +1481,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"external-service:" + api.String(): genVerifyServiceWatch("api", "", "dc1", false),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "external-service:" + api.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -1564,7 +1574,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"service-leaf:" + db.String(): genVerifyLeafWatch("db", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "service-leaf:" + db.String(),
 							Result:        issuedCert,
@@ -1582,7 +1592,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						serviceIntentionsIDPrefix + db.String(): genVerifyIntentionWatch("db", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: serviceIntentionsIDPrefix + db.String(),
 							Result:        dbIxnMatch,
@@ -1603,7 +1613,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						serviceConfigIDPrefix + db.String(): genVerifyResolvedConfigWatch("db", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: serviceConfigIDPrefix + db.String(),
 							Result:        dbConfig,
@@ -1622,7 +1632,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"service-resolver:" + db.String(): genVerifyResolverWatch("db", "dc1", structs.ServiceResolver),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "service-resolver:" + db.String(),
 							Result:        dbResolver,
@@ -1642,7 +1652,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: gatewayServicesWatchID,
 							Result: &structs.IndexedGatewayServices{
@@ -1730,7 +1740,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					},
 				},
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: leafWatchID,
@@ -1814,7 +1824,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				// Valid snapshot after roots, leaf, and intentions
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: leafWatchID,
@@ -1857,7 +1867,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						leafWatchID:       genVerifyLeafWatch("api", "dc1"),
 						intentionsWatchID: genVerifyIntentionWatch("api", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: intentionUpstreamsID,
 							Result: &structs.IndexedServiceList{
@@ -1900,7 +1910,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							OverrideMeshGateway:    structs.MeshGatewayConfig{Mode: structs.MeshGatewayModeRemote},
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "discovery-chain:" + dbUID.String(),
 							Result: &structs.DiscoveryChainResponse{
@@ -1918,7 +1928,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 					requiredWatches: map[string]verifyWatchRequest{
 						"upstream-target:db.default.default.dc1:" + dbUID.String(): genVerifyServiceWatch("db", "", "dc1", true),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -2069,7 +2079,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							OverrideMeshGateway:    structs.MeshGatewayConfig{Mode: structs.MeshGatewayModeRemote},
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "discovery-chain:" + dbUID.String(),
 							Result: &structs.DiscoveryChainResponse{
@@ -2096,7 +2106,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				{
 					// Receive a new upstream target event without proxy1.
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -2177,7 +2187,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				{
 					// Receive a new upstream target event with a conflicting passthrough address
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "upstream-target:api.default.default.dc1:" + apiUID.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -2259,7 +2269,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				{
 					// Event with no nodes should clean up addrs
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "upstream-target:api.default.default.dc1:" + apiUID.String(),
 							Result: &structs.IndexedCheckServiceNodes{
@@ -2289,7 +2299,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 						leafWatchID:       genVerifyLeafWatch("api", "dc1"),
 						intentionsWatchID: genVerifyIntentionWatch("api", "dc1"),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: intentionUpstreamsID,
 							Result: &structs.IndexedServiceList{
@@ -2382,7 +2392,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				// Valid snapshot after roots, leaf, and intentions
 				{
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: leafWatchID,
@@ -2428,7 +2438,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							OverrideMeshGateway:  structs.MeshGatewayConfig{Mode: structs.MeshGatewayModeLocal},
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: "discovery-chain:" + upstreamIDForDC2(dbUID).String(),
 							Result: &structs.DiscoveryChainResponse{
@@ -2465,7 +2475,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 							OverrideMeshGateway:  structs.MeshGatewayConfig{Mode: structs.MeshGatewayModeLocal},
 						}),
 					},
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						{
 							CorrelationID: intentionUpstreamsID,
 							Result: &structs.IndexedServiceList{
@@ -2557,7 +2567,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 				},
 				{
 					// This time add the events
-					events: []cache.UpdateEvent{
+					events: []UpdateEvent{
 						rootWatchEvent(),
 						{
 							CorrelationID: leafWatchID,
@@ -2607,7 +2617,7 @@ func TestState_WatchesAndUpdates(t *testing.T) {
 			state, err := newState(&tc.ns, "", stateConfig{
 				logger: testutil.Logger(t),
 				cache:  cn,
-				health: &health.Client{Cache: cn, CacheName: cachetype.HealthServicesName},
+				health: &HealthWrapper{&health.Client{Cache: cn, CacheName: cachetype.HealthServicesName}},
 				source: &structs.QuerySource{
 					Datacenter: tc.sourceDC,
 				},

agent/proxycfg/terminating_gateway.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"strings"
 
-	"github.com/hashicorp/consul/agent/cache"
 	cachetype "github.com/hashicorp/consul/agent/cache-types"
 	"github.com/hashicorp/consul/agent/structs"
 )
@@ -68,7 +67,7 @@ func (s *handlerTerminatingGateway) initialize(ctx context.Context) (ConfigSnaps
 	return snap, nil
 }
 
-func (s *handlerTerminatingGateway) handleUpdate(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error {
+func (s *handlerTerminatingGateway) handleUpdate(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error {
 	if u.Err != nil {
 		return fmt.Errorf("error filling agent cache: %v", u.Err)
 	}

agent/proxycfg/testing.go

@@ -672,7 +672,7 @@ type noopCacheNotifier struct{}
 
 var _ CacheNotifier = (*noopCacheNotifier)(nil)
 
-func (*noopCacheNotifier) Notify(_ context.Context, _ string, _ cache.Request, _ string, _ chan<- cache.UpdateEvent) error {
+func (*noopCacheNotifier) Notify(_ context.Context, _ string, _ cache.Request, _ string, _ chan<- UpdateEvent) error {
 	return nil
 }
 
@@ -680,7 +680,7 @@ type noopHealth struct{}
 
 var _ Health = (*noopHealth)(nil)
 
-func (*noopHealth) Notify(_ context.Context, _ structs.ServiceSpecificRequest, _ string, _ chan<- cache.UpdateEvent) error {
+func (*noopHealth) Notify(_ context.Context, _ structs.ServiceSpecificRequest, _ string, _ chan<- UpdateEvent) error {
 	return nil
 }
 
@@ -698,7 +698,7 @@ func testConfigSnapshotFixture(
 	ns *structs.NodeService,
 	nsFn func(ns *structs.NodeService),
 	serverSNIFn ServerSNIFunc,
-	updates []cache.UpdateEvent,
+	updates []UpdateEvent,
 ) *ConfigSnapshot {
 	const token = ""
 
@@ -750,15 +750,15 @@ func testConfigSnapshotFixture(
 	return &snap
 }
 
-func testSpliceEvents(base, extra []cache.UpdateEvent) []cache.UpdateEvent {
+func testSpliceEvents(base, extra []UpdateEvent) []UpdateEvent {
 	if len(extra) == 0 {
 		return base
 	}
 	var (
-		hasExtra      = make(map[string]cache.UpdateEvent)
+		hasExtra      = make(map[string]UpdateEvent)
 		completeExtra = make(map[string]struct{})
 
-		allEvents []cache.UpdateEvent
+		allEvents []UpdateEvent
 	)
 
 	for _, e := range extra {

agent/proxycfg/testing_connect_proxy.go

@@ -4,14 +4,13 @@ import (
 	"github.com/mitchellh/go-testing-interface"
 	"github.com/stretchr/testify/assert"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/connect"
 	"github.com/hashicorp/consul/agent/consul/discoverychain"
 	"github.com/hashicorp/consul/agent/structs"
 )
 
 // TestConfigSnapshot returns a fully populated snapshot
-func TestConfigSnapshot(t testing.T, nsFn func(ns *structs.NodeService), extraUpdates []cache.UpdateEvent) *ConfigSnapshot {
+func TestConfigSnapshot(t testing.T, nsFn func(ns *structs.NodeService), extraUpdates []UpdateEvent) *ConfigSnapshot {
 	roots, leaf := TestCerts(t)
 
 	// no entries implies we'll get a default chain
@@ -29,7 +28,7 @@ func TestConfigSnapshot(t testing.T, nsFn func(ns *structs.NodeService), extraUp
 		webSN = structs.ServiceIDString("web", nil)
 	)
 
-	baseEvents := []cache.UpdateEvent{
+	baseEvents := []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -94,7 +93,7 @@ func TestConfigSnapshotDiscoveryChain(
 	t testing.T,
 	variation string,
 	nsFn func(ns *structs.NodeService),
-	extraUpdates []cache.UpdateEvent,
+	extraUpdates []UpdateEvent,
 	additionalEntries ...structs.ConfigEntry,
 ) *ConfigSnapshot {
 	roots, leaf := TestCerts(t)
@@ -108,7 +107,7 @@ func TestConfigSnapshotDiscoveryChain(
 		webSN = structs.ServiceIDString("web", nil)
 	)
 
-	baseEvents := testSpliceEvents([]cache.UpdateEvent{
+	baseEvents := testSpliceEvents([]UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -171,7 +170,7 @@ func TestConfigSnapshotExposeConfig(t testing.T, nsFn func(ns *structs.NodeServi
 		webSN = structs.ServiceIDString("web", nil)
 	)
 
-	baseEvents := []cache.UpdateEvent{
+	baseEvents := []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -252,7 +251,7 @@ func TestConfigSnapshotGRPCExposeHTTP1(t testing.T) *ConfigSnapshot {
 		},
 		Meta:            nil,
 		TaggedAddresses: nil,
-	}, nil, nil, []cache.UpdateEvent{
+	}, nil, nil, []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,

agent/proxycfg/testing_ingress_gateway.go

@@ -7,7 +7,6 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/hashicorp/consul/acl"
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/connect"
 	"github.com/hashicorp/consul/agent/consul/discoverychain"
 	"github.com/hashicorp/consul/agent/structs"
@@ -21,7 +20,7 @@ func TestConfigSnapshotIngressGateway(
 	variation string,
 	nsFn func(ns *structs.NodeService),
 	configFn func(entry *structs.IngressGatewayConfigEntry),
-	extraUpdates []cache.UpdateEvent,
+	extraUpdates []UpdateEvent,
 	additionalEntries ...structs.ConfigEntry,
 ) *ConfigSnapshot {
 	roots, placeholderLeaf := TestCerts(t)
@@ -47,7 +46,7 @@ func TestConfigSnapshotIngressGateway(
 		configFn(entry)
 	}
 
-	baseEvents := []cache.UpdateEvent{
+	baseEvents := []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -71,7 +70,7 @@ func TestConfigSnapshotIngressGateway(
 	}
 
 	if populateServices {
-		baseEvents = testSpliceEvents(baseEvents, []cache.UpdateEvent{{
+		baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
 				Services: []*structs.GatewayService{
@@ -155,7 +154,7 @@ func TestConfigSnapshotIngressGatewaySDS_GatewayLevel_MixedTLS(t testing.T) *Con
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -270,7 +269,7 @@ func TestConfigSnapshotIngressGatewaySDS_GatewayAndListenerLevel_HTTP(t testing.
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -344,7 +343,7 @@ func TestConfigSnapshotIngressGatewaySDS_ServiceLevel(t testing.T) *ConfigSnapsh
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -434,7 +433,7 @@ func TestConfigSnapshotIngressGatewaySDS_ListenerAndServiceLevel(t testing.T) *C
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -519,7 +518,7 @@ func TestConfigSnapshotIngressGatewaySDS_MixedNoTLS(t testing.T) *ConfigSnapshot
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -601,7 +600,7 @@ func TestConfigSnapshotIngressGateway_MixedListeners(t testing.T) *ConfigSnapsho
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -717,7 +716,7 @@ func TestConfigSnapshotIngress_HTTPMultipleServices(t testing.T) *ConfigSnapshot
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -830,7 +829,7 @@ func TestConfigSnapshotIngress_MultipleListenersDuplicateService(t testing.T) *C
 				},
 			},
 		}
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: gatewayServicesWatchID,
 			Result: &structs.IndexedGatewayServices{
@@ -893,7 +892,7 @@ func TestConfigSnapshotIngressGatewayWithChain(
 	}
 
 	var (
-		updates  []cache.UpdateEvent
+		updates  []UpdateEvent
 		configFn func(entry *structs.IngressGatewayConfigEntry)
 
 		populateServices                      bool
@@ -1088,7 +1087,7 @@ func TestConfigSnapshotIngressGatewayWithChain(
 			fooEntMeta.PartitionOrDefault(), "dc1",
 			connect.TestClusterID+".consul", nil, entries...)
 
-		updates = []cache.UpdateEvent{
+		updates = []UpdateEvent{
 			{
 				CorrelationID: gatewayServicesWatchID,
 				Result: &structs.IndexedGatewayServices{
@@ -1218,7 +1217,7 @@ func TestConfigSnapshotIngressGateway_TLSMinVersionListenersGatewayDefaults(t te
 					},
 				},
 			}
-		}, []cache.UpdateEvent{
+		}, []UpdateEvent{
 			{
 				CorrelationID: gatewayServicesWatchID,
 				Result: &structs.IndexedGatewayServices{
@@ -1336,7 +1335,7 @@ func TestConfigSnapshotIngressGateway_SingleTLSListener(t testing.T) *ConfigSnap
 					},
 				},
 			}
-		}, []cache.UpdateEvent{
+		}, []UpdateEvent{
 			{
 				CorrelationID: gatewayServicesWatchID,
 				Result: &structs.IndexedGatewayServices{
@@ -1436,7 +1435,7 @@ func TestConfigSnapshotIngressGateway_TLSMixedMinVersionListeners(t testing.T) *
 					},
 				},
 			}
-		}, []cache.UpdateEvent{
+		}, []UpdateEvent{
 			{
 				CorrelationID: gatewayServicesWatchID,
 				Result: &structs.IndexedGatewayServices{

agent/proxycfg/testing_mesh_gateway.go

@@ -6,11 +6,10 @@ import (
 
 	"github.com/mitchellh/go-testing-interface"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/structs"
 )
 
-func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *structs.NodeService), extraUpdates []cache.UpdateEvent) *ConfigSnapshot {
+func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *structs.NodeService), extraUpdates []UpdateEvent) *ConfigSnapshot {
 	roots, _ := TestCerts(t)
 
 	var (
@@ -38,7 +37,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 		useFederationStates = false
 		deleteCrossDCEntry = false
 	case "service-subsets":
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: serviceResolversWatchID,
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -60,7 +59,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "service-subsets2": // TODO(rb): make this merge with 'service-subsets'
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: serviceResolversWatchID,
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -95,7 +94,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "default-service-subsets2": // TODO(rb): rename to strip the 2 when the prior is merged with 'service-subsets'
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: serviceResolversWatchID,
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -132,7 +131,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "ignore-extra-resolvers":
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: serviceResolversWatchID,
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -169,7 +168,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "service-timeouts":
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: serviceResolversWatchID,
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -192,7 +191,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "non-hash-lb-injected":
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: "service-resolvers", // serviceResolversWatchID
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -220,7 +219,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			},
 		})
 	case "hash-lb-ignored":
-		extraUpdates = append(extraUpdates, cache.UpdateEvent{
+		extraUpdates = append(extraUpdates, UpdateEvent{
 			CorrelationID: "service-resolvers", // serviceResolversWatchID
 			Result: &structs.IndexedConfigEntries{
 				Kind: structs.ServiceResolver,
@@ -253,7 +252,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 		return nil
 	}
 
-	baseEvents := []cache.UpdateEvent{
+	baseEvents := []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -278,7 +277,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 	}
 
 	if populateServices || useFederationStates {
-		baseEvents = testSpliceEvents(baseEvents, []cache.UpdateEvent{
+		baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{
 			{
 				CorrelationID: datacentersWatchID,
 				Result:        &[]string{"dc1", "dc2", "dc4", "dc6"},
@@ -291,7 +290,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			foo = structs.NewServiceName("foo", nil)
 			bar = structs.NewServiceName("bar", nil)
 		)
-		baseEvents = testSpliceEvents(baseEvents, []cache.UpdateEvent{
+		baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{
 			{
 				CorrelationID: "mesh-gateway:dc2",
 				Result: &structs.IndexedNodesWithGateways{
@@ -349,7 +348,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 		})
 
 		if deleteCrossDCEntry {
-			baseEvents = testSpliceEvents(baseEvents, []cache.UpdateEvent{
+			baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{
 				{
 					// Have the cross-dc query mechanism not work for dc2 so
 					// fedstates will infill.
@@ -399,7 +398,7 @@ func TestConfigSnapshotMeshGateway(t testing.T, variant string, nsFn func(ns *st
 			}
 		}
 
-		baseEvents = testSpliceEvents(baseEvents, []cache.UpdateEvent{
+		baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{
 			{
 				CorrelationID: federationStateListGatewaysWatchID,
 				Result: &structs.DatacenterIndexedCheckServiceNodes{

agent/proxycfg/testing_terminating_gateway.go

@@ -3,8 +3,6 @@ package proxycfg
 import (
 	"github.com/mitchellh/go-testing-interface"
 
-	"github.com/hashicorp/consul/agent/cache"
-	agentcache "github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/structs"
 )
 
@@ -12,7 +10,7 @@ func TestConfigSnapshotTerminatingGateway(
 	t testing.T,
 	populateServices bool,
 	nsFn func(ns *structs.NodeService),
-	extraUpdates []agentcache.UpdateEvent,
+	extraUpdates []UpdateEvent,
 ) *ConfigSnapshot {
 	roots, _ := TestCerts(t)
 
@@ -23,7 +21,7 @@ func TestConfigSnapshotTerminatingGateway(
 		cache = structs.NewServiceName("cache", nil)
 	)
 
-	baseEvents := []agentcache.UpdateEvent{
+	baseEvents := []UpdateEvent{
 		{
 			CorrelationID: rootsWatchID,
 			Result:        roots,
@@ -158,7 +156,7 @@ func TestConfigSnapshotTerminatingGateway(
 			},
 		}
 
-		baseEvents = testSpliceEvents(baseEvents, []agentcache.UpdateEvent{
+		baseEvents = testSpliceEvents(baseEvents, []UpdateEvent{
 			{
 				CorrelationID: gatewayServicesWatchID,
 				Result: &structs.IndexedGatewayServices{
@@ -356,7 +354,7 @@ func testConfigSnapshotTerminatingGatewayServiceSubsets(t testing.T, alsoAdjustC
 		cache = structs.NewServiceName("cache", nil)
 	)
 
-	events := []agentcache.UpdateEvent{
+	events := []UpdateEvent{
 		{
 			CorrelationID: serviceResolverIDPrefix + web.String(),
 			Result: &structs.ConfigEntryResponse{
@@ -384,7 +382,7 @@ func testConfigSnapshotTerminatingGatewayServiceSubsets(t testing.T, alsoAdjustC
 	}
 
 	if alsoAdjustCache {
-		events = testSpliceEvents(events, []agentcache.UpdateEvent{
+		events = testSpliceEvents(events, []UpdateEvent{
 			{
 				CorrelationID: serviceResolverIDPrefix + cache.String(),
 				Result: &structs.ConfigEntryResponse{
@@ -414,7 +412,7 @@ func testConfigSnapshotTerminatingGatewayServiceSubsets(t testing.T, alsoAdjustC
 func TestConfigSnapshotTerminatingGatewayDefaultServiceSubset(t testing.T) *ConfigSnapshot {
 	web := structs.NewServiceName("web", nil)
 
-	return TestConfigSnapshotTerminatingGateway(t, true, nil, []agentcache.UpdateEvent{
+	return TestConfigSnapshotTerminatingGateway(t, true, nil, []UpdateEvent{
 		{
 			CorrelationID: serviceResolverIDPrefix + web.String(),
 			Result: &structs.ConfigEntryResponse{
@@ -498,7 +496,7 @@ func testConfigSnapshotTerminatingGatewayLBConfig(t testing.T, variant string) *
 		return nil
 	}
 
-	return TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+	return TestConfigSnapshotTerminatingGateway(t, true, nil, []UpdateEvent{
 		{
 			CorrelationID: serviceConfigIDPrefix + web.String(),
 			Result: &structs.ServiceConfigResponse{
@@ -521,7 +519,7 @@ func testConfigSnapshotTerminatingGatewayLBConfig(t testing.T, variant string) *
 }
 
 func TestConfigSnapshotTerminatingGatewaySNI(t testing.T) *ConfigSnapshot {
-	return TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+	return TestConfigSnapshotTerminatingGateway(t, true, nil, []UpdateEvent{
 		{
 			CorrelationID: "gateway-services",
 			Result: &structs.IndexedGatewayServices{
@@ -550,7 +548,7 @@ func TestConfigSnapshotTerminatingGatewayHostnameSubsets(t testing.T) *ConfigSna
 		cache = structs.NewServiceName("cache", nil)
 	)
 
-	return TestConfigSnapshotTerminatingGateway(t, true, nil, []agentcache.UpdateEvent{
+	return TestConfigSnapshotTerminatingGateway(t, true, nil, []UpdateEvent{
 		{
 			CorrelationID: serviceResolverIDPrefix + api.String(),
 			Result: &structs.ConfigEntryResponse{
@@ -600,7 +598,7 @@ func TestConfigSnapshotTerminatingGatewayIgnoreExtraResolvers(t testing.T) *Conf
 		notfound = structs.NewServiceName("notfound", nil)
 	)
 
-	return TestConfigSnapshotTerminatingGateway(t, true, nil, []agentcache.UpdateEvent{
+	return TestConfigSnapshotTerminatingGateway(t, true, nil, []UpdateEvent{
 		{
 			CorrelationID: serviceResolverIDPrefix + web.String(),
 			Result: &structs.ConfigEntryResponse{
@@ -648,9 +646,9 @@ func TestConfigSnapshotTerminatingGatewayIgnoreExtraResolvers(t testing.T) *Conf
 	})
 }
 
-func TestConfigSnapshotTerminatingGatewayWithLambdaService(t testing.T, extraUpdateEvents ...agentcache.UpdateEvent) *ConfigSnapshot {
+func TestConfigSnapshotTerminatingGatewayWithLambdaService(t testing.T, extraUpdateEvents ...UpdateEvent) *ConfigSnapshot {
 	web := structs.NewServiceName("web", nil)
-	updateEvents := append(extraUpdateEvents, agentcache.UpdateEvent{
+	updateEvents := append(extraUpdateEvents, UpdateEvent{
 		CorrelationID: serviceConfigIDPrefix + web.String(),
 		Result: &structs.ServiceConfigResponse{
 			ProxyConfig: map[string]interface{}{"protocol": "http"},
@@ -669,7 +667,7 @@ func TestConfigSnapshotTerminatingGatewayWithLambdaServiceAndServiceResolvers(t
 	web := structs.NewServiceName("web", nil)
 
 	return TestConfigSnapshotTerminatingGatewayWithLambdaService(t,
-		agentcache.UpdateEvent{
+		UpdateEvent{
 			CorrelationID: serviceResolverIDPrefix + web.String(),
 			Result: &structs.ConfigEntryResponse{
 				Entry: &structs.ServiceResolverConfigEntry{

agent/proxycfg/testing_tproxy.go

@@ -5,7 +5,6 @@ import (
 
 	"github.com/mitchellh/go-testing-interface"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/connect"
 	"github.com/hashicorp/consul/agent/consul/discoverychain"
 	"github.com/hashicorp/consul/agent/structs"
@@ -28,7 +27,7 @@ func TestConfigSnapshotTransparentProxy(t testing.T) *ConfigSnapshot {
 
 	return TestConfigSnapshot(t, func(ns *structs.NodeService) {
 		ns.Proxy.Mode = structs.ProxyModeTransparent
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: meshConfigEntryID,
 			Result: &structs.ConfigEntryResponse{
@@ -141,7 +140,7 @@ func TestConfigSnapshotTransparentProxyHTTPUpstream(t testing.T) *ConfigSnapshot
 
 	return TestConfigSnapshot(t, func(ns *structs.NodeService) {
 		ns.Proxy.Mode = structs.ProxyModeTransparent
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: meshConfigEntryID,
 			Result: &structs.ConfigEntryResponse{
@@ -245,7 +244,7 @@ func TestConfigSnapshotTransparentProxyCatalogDestinationsOnly(t testing.T) *Con
 
 	return TestConfigSnapshot(t, func(ns *structs.NodeService) {
 		ns.Proxy.Mode = structs.ProxyModeTransparent
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: meshConfigEntryID,
 			Result: &structs.ConfigEntryResponse{
@@ -335,7 +334,7 @@ func TestConfigSnapshotTransparentProxyDialDirectly(t testing.T) *ConfigSnapshot
 
 	return TestConfigSnapshot(t, func(ns *structs.NodeService) {
 		ns.Proxy.Mode = structs.ProxyModeTransparent
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: meshConfigEntryID,
 			Result: &structs.ConfigEntryResponse{
@@ -473,7 +472,7 @@ func TestConfigSnapshotTransparentProxyTerminatingGatewayCatalogDestinationsOnly
 
 	return TestConfigSnapshot(t, func(ns *structs.NodeService) {
 		ns.Proxy.Mode = structs.ProxyModeTransparent
-	}, []cache.UpdateEvent{
+	}, []UpdateEvent{
 		{
 			CorrelationID: meshConfigEntryID,
 			Result: &structs.ConfigEntryResponse{

agent/proxycfg/testing_upstreams.go

@@ -5,7 +5,6 @@ import (
 
 	"github.com/mitchellh/go-testing-interface"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/connect"
 	"github.com/hashicorp/consul/agent/consul/discoverychain"
 	"github.com/hashicorp/consul/agent/structs"
@@ -16,7 +15,7 @@ func setupTestVariationConfigEntriesAndSnapshot(
 	variation string,
 	upstreams structs.Upstreams,
 	additionalEntries ...structs.ConfigEntry,
-) []cache.UpdateEvent {
+) []UpdateEvent {
 	var (
 		dbUpstream = upstreams[0]
 
@@ -25,7 +24,7 @@ func setupTestVariationConfigEntriesAndSnapshot(
 
 	dbChain := setupTestVariationDiscoveryChain(t, variation, additionalEntries...)
 
-	events := []cache.UpdateEvent{
+	events := []UpdateEvent{
 		{
 			CorrelationID: "discovery-chain:" + dbUID.String(),
 			Result: &structs.DiscoveryChainResponse{
@@ -46,14 +45,14 @@ func setupTestVariationConfigEntriesAndSnapshot(
 	case "simple":
 	case "external-sni":
 	case "failover":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:fail.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesAlternate(t),
 			},
 		})
 	case "failover-through-remote-gateway-triggered":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatus(t, "critical"),
@@ -61,26 +60,26 @@ func setupTestVariationConfigEntriesAndSnapshot(
 		})
 		fallthrough
 	case "failover-through-remote-gateway":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc2:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesDC2(t),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "mesh-gateway:dc2:" + dbUID.String(),
 			Result: &structs.IndexedNodesWithGateways{
 				Nodes: TestGatewayNodesDC2(t),
 			},
 		})
 	case "failover-through-double-remote-gateway-triggered":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatus(t, "critical"),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc2:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatusDC2(t, "critical"),
@@ -88,26 +87,26 @@ func setupTestVariationConfigEntriesAndSnapshot(
 		})
 		fallthrough
 	case "failover-through-double-remote-gateway":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc3:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesDC2(t),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "mesh-gateway:dc2:" + dbUID.String(),
 			Result: &structs.IndexedNodesWithGateways{
 				Nodes: TestGatewayNodesDC2(t),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "mesh-gateway:dc3:" + dbUID.String(),
 			Result: &structs.IndexedNodesWithGateways{
 				Nodes: TestGatewayNodesDC3(t),
 			},
 		})
 	case "failover-through-local-gateway-triggered":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatus(t, "critical"),
@@ -115,26 +114,26 @@ func setupTestVariationConfigEntriesAndSnapshot(
 		})
 		fallthrough
 	case "failover-through-local-gateway":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc2:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesDC2(t),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "mesh-gateway:dc1:" + dbUID.String(),
 			Result: &structs.IndexedNodesWithGateways{
 				Nodes: TestGatewayNodesDC1(t),
 			},
 		})
 	case "failover-through-double-local-gateway-triggered":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatus(t, "critical"),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc2:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesInStatusDC2(t, "critical"),
@@ -142,26 +141,26 @@ func setupTestVariationConfigEntriesAndSnapshot(
 		})
 		fallthrough
 	case "failover-through-double-local-gateway":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:db.default.default.dc3:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesDC2(t),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "mesh-gateway:dc1:" + dbUID.String(),
 			Result: &structs.IndexedNodesWithGateways{
 				Nodes: TestGatewayNodesDC1(t),
 			},
 		})
 	case "splitter-with-resolver-redirect-multidc":
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:v1.db.default.default.dc1:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodes(t, "db"),
 			},
 		})
-		events = append(events, cache.UpdateEvent{
+		events = append(events, UpdateEvent{
 			CorrelationID: "upstream-target:v2.db.default.default.dc2:" + dbUID.String(),
 			Result: &structs.IndexedCheckServiceNodes{
 				Nodes: TestUpstreamNodesDC2(t),

agent/proxycfg/upstreams.go

@@ -9,7 +9,6 @@ import (
 	"github.com/mitchellh/mapstructure"
 
 	"github.com/hashicorp/consul/acl"
-	"github.com/hashicorp/consul/agent/cache"
 	cachetype "github.com/hashicorp/consul/agent/cache-types"
 	"github.com/hashicorp/consul/agent/structs"
 )
@@ -18,7 +17,7 @@ type handlerUpstreams struct {
 	handlerState
 }
 
-func (s *handlerUpstreams) handleUpdateUpstreams(ctx context.Context, u cache.UpdateEvent, snap *ConfigSnapshot) error {
+func (s *handlerUpstreams) handleUpdateUpstreams(ctx context.Context, u UpdateEvent, snap *ConfigSnapshot) error {
 	if u.Err != nil {
 		return fmt.Errorf("error filling agent cache: %v", u.Err)
 	}

agent/rpcclient/health/health.go

@@ -26,12 +26,12 @@ type NetRPC interface {
 
 type CacheGetter interface {
 	Get(ctx context.Context, t string, r cache.Request) (interface{}, cache.ResultMeta, error)
-	Notify(ctx context.Context, t string, r cache.Request, cID string, ch chan<- cache.UpdateEvent) error
+	NotifyCallback(ctx context.Context, t string, r cache.Request, cID string, cb cache.Callback) error
 }
 
 type MaterializedViewStore interface {
 	Get(ctx context.Context, req submatview.Request) (submatview.Result, error)
-	Notify(ctx context.Context, req submatview.Request, cID string, ch chan<- cache.UpdateEvent) error
+	NotifyCallback(ctx context.Context, req submatview.Request, cID string, cb cache.Callback) error
 }
 
 func (c *Client) ServiceNodes(
@@ -91,14 +91,14 @@ func (c *Client) Notify(
 	ctx context.Context,
 	req structs.ServiceSpecificRequest,
 	correlationID string,
-	ch chan<- cache.UpdateEvent,
+	cb cache.Callback,
 ) error {
 	if c.useStreaming(req) {
 		sr := c.newServiceRequest(req)
-		return c.ViewStore.Notify(ctx, sr, correlationID, ch)
+		return c.ViewStore.NotifyCallback(ctx, sr, correlationID, cb)
 	}
 
-	return c.Cache.Notify(ctx, c.CacheName, &req, correlationID, ch)
+	return c.Cache.NotifyCallback(ctx, c.CacheName, &req, correlationID, cb)
 }
 
 func (c *Client) useStreaming(req structs.ServiceSpecificRequest) bool {

agent/rpcclient/health/health_test.go

@@ -152,7 +152,7 @@ func (f *fakeCache) Get(_ context.Context, t string, _ cache.Request) (interface
 	return result, cache.ResultMeta{}, nil
 }
 
-func (f *fakeCache) Notify(_ context.Context, t string, _ cache.Request, _ string, _ chan<- cache.UpdateEvent) error {
+func (f *fakeCache) NotifyCallback(_ context.Context, t string, _ cache.Request, _ string, _ cache.Callback) error {
 	f.calls = append(f.calls, t)
 	return nil
 }
@@ -175,7 +175,7 @@ func (f *fakeViewStore) Get(_ context.Context, req submatview.Request) (submatvi
 	return submatview.Result{Value: &structs.IndexedCheckServiceNodes{}}, nil
 }
 
-func (f *fakeViewStore) Notify(_ context.Context, req submatview.Request, _ string, _ chan<- cache.UpdateEvent) error {
+func (f *fakeViewStore) NotifyCallback(_ context.Context, req submatview.Request, _ string, _ cache.Callback) error {
 	f.calls = append(f.calls, req)
 	return nil
 }

agent/submatview/store.go

@@ -149,6 +149,23 @@ func (s *Store) Notify(
 	req Request,
 	correlationID string,
 	updateCh chan<- cache.UpdateEvent,
+) error {
+	return s.NotifyCallback(ctx, req, correlationID, func(ctx context.Context, event cache.UpdateEvent) {
+		select {
+		case updateCh <- event:
+		case <-ctx.Done():
+			return
+		}
+	})
+}
+
+// NotifyCallback subscribes to updates of the entry identified by req in the
+// same way as Notify, but accepts a callback function instead of a channel.
+func (s *Store) NotifyCallback(
+	ctx context.Context,
+	req Request,
+	correlationID string,
+	cb cache.Callback,
 ) error {
 	info := req.CacheInfo()
 	key, materializer, err := s.readEntry(req)
@@ -174,16 +191,11 @@ func (s *Store) Notify(
 			}
 
 			index = result.Index
-			u := cache.UpdateEvent{
+			cb(ctx, cache.UpdateEvent{
 				CorrelationID: correlationID,
 				Result:        result.Value,
 				Meta:          cache.ResultMeta{Index: result.Index, Hit: result.Cached},
-			}
+			})
-			select {
-			case updateCh <- u:
-			case <-ctx.Done():
-				return
-			}
 		}
 	}()
 	return nil

agent/submatview/store_integration_test.go

@@ -320,7 +320,12 @@ func (c *consumer) Consume(ctx context.Context, maxIndex uint64) error {
 
 	group, cctx := errgroup.WithContext(ctx)
 	group.Go(func() error {
-		return c.healthClient.Notify(cctx, req, "", updateCh)
+		return c.healthClient.Notify(cctx, req, "", func(ctx context.Context, event cache.UpdateEvent) {
+			select {
+			case updateCh <- event:
+			case <-ctx.Done():
+			}
+		})
 	})
 	group.Go(func() error {
 		var idx uint64

agent/xds/clusters_test.go

@@ -13,7 +13,6 @@ import (
 	testinf "github.com/mitchellh/go-testing-interface"
 	"github.com/stretchr/testify/require"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/proxycfg"
 	"github.com/hashicorp/consul/agent/structs"
 	"github.com/hashicorp/consul/agent/xds/proxysupport"
@@ -41,7 +40,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-outgoing-min-version-auto",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -60,7 +59,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-outgoing-min-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -79,7 +78,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-outgoing-max-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -98,7 +97,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-outgoing-cipher-suites",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -406,7 +405,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "ingress-gateway-with-tls-outgoing-min-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -425,7 +424,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "ingress-gateway-with-tls-outgoing-max-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -444,7 +443,7 @@ func TestClustersFromSnapshot(t *testing.T) {
 		{
 			name: "ingress-gateway-with-tls-outgoing-cipher-suites",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotIngressGateway(t, true, "tcp", "default", nil, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{

agent/xds/listeners_test.go

@@ -13,7 +13,6 @@ import (
 	testinf "github.com/mitchellh/go-testing-interface"
 	"github.com/stretchr/testify/require"
 
-	"github.com/hashicorp/consul/agent/cache"
 	"github.com/hashicorp/consul/agent/proxycfg"
 	"github.com/hashicorp/consul/agent/structs"
 	"github.com/hashicorp/consul/agent/xds/proxysupport"
@@ -46,7 +45,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-outgoing-min-version-auto",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -65,7 +64,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-incoming-min-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -84,7 +83,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-incoming-max-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -103,7 +102,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "connect-proxy-with-tls-incoming-cipher-suites",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshot(t, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshot(t, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -173,7 +172,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 					func(ns *structs.NodeService) {
 						ns.Proxy.Config["protocol"] = "http"
 					},
-					[]cache.UpdateEvent{
+					[]proxycfg.UpdateEvent{
 						{
 							CorrelationID: "mesh",
 							Result: &structs.ConfigEntryResponse{
@@ -580,7 +579,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "terminating-gateway-with-tls-incoming-min-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -599,7 +598,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "terminating-gateway-with-tls-incoming-max-version",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -618,7 +617,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 		{
 			name: "terminating-gateway-with-tls-incoming-cipher-suites",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
-				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "mesh",
 						Result: &structs.ConfigEntryResponse{
@@ -677,7 +676,7 @@ func TestListenersFromSnapshot(t *testing.T) {
 			name: "terminating-gateway-no-api-cert",
 			create: func(t testinf.T) *proxycfg.ConfigSnapshot {
 				api := structs.NewServiceName("api", nil)
-				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []cache.UpdateEvent{
+				return proxycfg.TestConfigSnapshotTerminatingGateway(t, true, nil, []proxycfg.UpdateEvent{
 					{
 						CorrelationID: "service-leaf:" + api.String(), // serviceLeafIDPrefix
 						Result:        nil,                            // tombstone this