cache: add default logger

go.mod

@@ -11,6 +11,8 @@ require (
 	github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4
 	github.com/stretchr/testify v1.7.0
 	go.opentelemetry.io/proto/otlp v0.7.0
+	golang.org/x/net v0.0.0-20201021035429-f5854403a974 // indirect
+	golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4 // indirect
 	google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013
 	google.golang.org/grpc v1.36.0
 	google.golang.org/protobuf v1.25.0

go.sum

@@ -63,8 +63,9 @@ golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73r
 golang.org/x/net v0.0.0-20190213061140-3a22650c66bd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20200822124328-c89045814202 h1:VvcQYSHwXgi7W+TpUR6A9g6Up98WAHf3f/ulnJ62IyA=
 golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974 h1:IX6qOQeG5uLjB/hjjwjedwfjND0hgjPMMyO1RoIXQNI=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -74,10 +75,14 @@ golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4 h1:myAQVi0cGEoqQVR5POX+8RR2mrocKqNN1hmeMqhX27k=
+golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=

pkg/cache/v3/simple.go

@@ -102,6 +102,10 @@ func NewSnapshotCache(ads bool, hash NodeHash, logger log.Logger) SnapshotCache
 }
 
 func newSnapshotCache(ads bool, hash NodeHash, logger log.Logger) *snapshotCache {
+	if logger == nil {
+		logger = log.NewDefaultLogger()
+	}
+
 	cache := &snapshotCache{
 		log:       logger,
 		ads:       ads,
@@ -170,12 +174,12 @@ func (cache *snapshotCache) sendHeartbeats(ctx context.Context, node string) {
 			if len(resourcesWithTTL) == 0 {
 				continue
 			}
-			if cache.log != nil {
-				cache.log.Debugf("respond open watch %d%v with heartbeat for version %q", id, watch.Request.ResourceNames, version)
+			cache.log.Debugf("respond open watch %d%v with heartbeat for version %q", id, watch.Request.ResourceNames, version)
+			err := cache.respond(ctx, watch.Request, watch.Response, resourcesWithTTL, version, true)
+			if err != nil {
+				cache.log.Errorf("received error when attempting to respond to watches: %v", err)
 			}
 
-			_ = cache.respond(ctx, watch.Request, watch.Response, resourcesWithTTL, version, true)
-
 			// The watch must be deleted and we must rely on the client to ack this response to create a new watch.
 			delete(info.watches, id)
 		}
@@ -198,9 +202,8 @@ func (cache *snapshotCache) SetSnapshot(ctx context.Context, node string, snapsh
 		for id, watch := range info.watches {
 			version := snapshot.GetVersion(watch.Request.TypeUrl)
 			if version != watch.Request.VersionInfo {
-				if cache.log != nil {
-					cache.log.Debugf("respond open watch %d%v with new version %q", id, watch.Request.ResourceNames, version)
-				}
+				cache.log.Debugf("respond open watch %d%v with new version %q", id, watch.Request.ResourceNames, version)
+
 				resources := snapshot.GetResourcesAndTTL(watch.Request.TypeUrl)
 				err := cache.respond(ctx, watch.Request, watch.Response, resources, version, false)
 				if err != nil {
@@ -309,10 +312,8 @@ func (cache *snapshotCache) CreateWatch(request *Request, value chan Response) f
 	// if the requested version is up-to-date or missing a response, leave an open watch
 	if !exists || request.VersionInfo == version {
 		watchID := cache.nextWatchID()
-		if cache.log != nil {
-			cache.log.Debugf("open watch %d for %s%v from nodeID %q, version %q", watchID,
-				request.TypeUrl, request.ResourceNames, nodeID, request.VersionInfo)
-		}
+		cache.log.Debugf("open watch %d for %s%v from nodeID %q, version %q", watchID, request.TypeUrl, request.ResourceNames, nodeID, request.VersionInfo)
+
 		info.mu.Lock()
 		info.watches[watchID] = ResponseWatch{Request: request, Response: value}
 		info.mu.Unlock()
@@ -351,16 +352,12 @@ func (cache *snapshotCache) respond(ctx context.Context, request *Request, value
 	// if they do not, then the watch is never responded, and it is expected that envoy makes another request
 	if len(request.ResourceNames) != 0 && cache.ads {
 		if err := superset(nameSet(request.ResourceNames), resources); err != nil {
-			if cache.log != nil {
-				cache.log.Warnf("ADS mode: not responding to request: %v", err)
-			}
+			cache.log.Warnf("ADS mode: not responding to request: %v", err)
 			return nil
 		}
 	}
-	if cache.log != nil {
-		cache.log.Debugf("respond %s%v version %q with version %q",
-			request.TypeUrl, request.ResourceNames, request.VersionInfo, version)
-	}
+
+	cache.log.Debugf("respond %s%v version %q with version %q", request.TypeUrl, request.ResourceNames, request.VersionInfo, version)
 
 	select {
 	case value <- createResponse(ctx, request, resources, version, heartbeat):
@@ -426,27 +423,19 @@ func (cache *snapshotCache) CreateDeltaWatch(request *DeltaRequest, state stream
 	if exists {
 		err := snapshot.ConstructVersionMap()
 		if err != nil {
-			if cache.log != nil {
-				cache.log.Errorf("failed to compute version for snapshot resources inline, waiting for next snapshot update")
-			}
+			cache.log.Errorf("failed to compute version for snapshot resources inline, waiting for next snapshot update")
 		}
 		response, err := cache.respondDelta(context.Background(), &snapshot, request, value, state)
 		if err != nil {
-			if cache.log != nil {
-				cache.log.Errorf("failed to respond with delta response, waiting for next snapshot update: %s", err)
-			}
+			cache.log.Errorf("failed to respond with delta response, waiting for next snapshot update: %s", err)
 		}
 
 		delayedResponse = response == nil
 	}
 
 	if delayedResponse {
 		watchID := cache.nextDeltaWatchID()
-		if cache.log != nil {
-			cache.log.Infof("open delta watch ID:%d for %s Resources:%v from nodeID: %q, system version %q", watchID,
-				t, state.GetResourceVersions(), nodeID, snapshot.GetVersion(t))
-		}
-
+		cache.log.Infof("open delta watch ID:%d for %s Resources:%v from nodeID: %q, system version %q", watchID, t, state.GetResourceVersions(), nodeID, snapshot.GetVersion(t))
 		info.SetDeltaResponseWatch(watchID, DeltaResponseWatch{Request: request, Response: value, StreamState: state})
 
 		return cache.cancelDeltaWatch(nodeID, watchID)
@@ -511,9 +500,7 @@ func (cache *snapshotCache) Fetch(ctx context.Context, request *Request) (Respon
 		// It might be beneficial to hold the request since Envoy will re-attempt the refresh.
 		version := snapshot.GetVersion(request.TypeUrl)
 		if request.VersionInfo == version {
-			if cache.log != nil {
-				cache.log.Warnf("skip fetch: version up to date")
-			}
+			cache.log.Warnf("skip fetch: version up to date")
 			return nil, &types.SkipFetchError{}
 		}
 
@@ -532,9 +519,7 @@ func (cache *snapshotCache) GetStatusInfo(node string) StatusInfo {
 
 	info, exists := cache.status[node]
 	if !exists {
-		if cache.log != nil {
-			cache.log.Warnf("node does not exist")
-		}
+		cache.log.Warnf("node does not exist")
 		return nil
 	}
 

pkg/log/default.go

@@ -0,0 +1,27 @@
+package log
+
+// DefaultLogger is enabled when no consuming clients provide
+// a logger to the server/cache subsystem
+type DefaultLogger struct {
+}
+
+// NewDefaultLogger creates a DefaultLogger which is a no-op to maintain current functionality
+func NewDefaultLogger() *DefaultLogger {
+	return &DefaultLogger{}
+}
+
+// Debugf logs a message at level debug on the standard logger.
+func (l *DefaultLogger) Debugf(format string, args ...interface{}) {
+}
+
+// Infof logs a message at level info on the standard logger.
+func (l *DefaultLogger) Infof(format string, args ...interface{}) {
+}
+
+// Warnf logs a message at level warn on the standard logger.
+func (l *DefaultLogger) Warnf(format string, args ...interface{}) {
+}
+
+// Errorf logs a message at level error on the standard logger.
+func (l *DefaultLogger) Errorf(format string, args ...interface{}) {
+}

pkg/log/log_test.go

@@ -69,3 +69,8 @@ func TestNilLoggerFuncs(t *testing.T) {
 	xdsLogger.Warnf("warn")
 	xdsLogger.Errorf("error")
 }
+
+func TestDefaultLogger(t *testing.T) {
+	logger := NewDefaultLogger()
+	assert.NotNil(t, logger)
+}

pkg/server/v3/gateway.go

@@ -25,16 +25,12 @@ import (
 
 	discovery "github.com/envoyproxy/go-control-plane/envoy/service/discovery/v3"
 	"github.com/envoyproxy/go-control-plane/pkg/cache/types"
-	"github.com/envoyproxy/go-control-plane/pkg/log"
 	"github.com/envoyproxy/go-control-plane/pkg/resource/v3"
 )
 
 // HTTPGateway is a custom implementation of [gRPC gateway](https://github.com/grpc-ecosystem/grpc-gateway)
 // specialized to Envoy xDS API.
 type HTTPGateway struct {
-	// Log is an optional log for errors in response write
-	Log log.Logger
-
 	// Server is the underlying gRPC server
 	Server Server
 }

pkg/server/v3/gateway_test.go

@@ -29,15 +29,6 @@ import (
 	"github.com/envoyproxy/go-control-plane/pkg/server/v3"
 )
 
-type logger struct {
-	t *testing.T
-}
-
-func (log logger) Debugf(format string, args ...interface{}) { log.t.Logf(format, args...) }
-func (log logger) Infof(format string, args ...interface{})  { log.t.Logf(format, args...) }
-func (log logger) Warnf(format string, args ...interface{})  { log.t.Logf(format, args...) }
-func (log logger) Errorf(format string, args ...interface{}) { log.t.Logf(format, args...) }
-
 func TestGateway(t *testing.T) {
 	config := makeMockConfigWatcher()
 	config.responses = map[string][]cache.Response{
@@ -63,7 +54,7 @@ func TestGateway(t *testing.T) {
 			},
 		},
 	}
-	gtw := server.HTTPGateway{Log: logger{t: t}, Server: server.NewServer(context.Background(), config, nil)}
+	gtw := server.HTTPGateway{Server: server.NewServer(context.Background(), config, nil)}
 
 	failCases := []struct {
 		path   string

pkg/test/main/main.go

@@ -170,7 +170,8 @@ func main() {
 	cb := &testv3.Callbacks{Signal: signal, Debug: debug}
 
 	// mux integration
-	config := cache.NewSnapshotCache(mode == resource.Ads, cache.IDHash{}, logger{})
+	// nil for logger uses default logger
+	config := cache.NewSnapshotCache(mode == resource.Ads, cache.IDHash{}, nil)
 	var configCache cache.Cache = config
 	typeURL := "type.googleapis.com/envoy.config.endpoint.v3.ClusterLoadAssignment"
 	eds := cache.NewLinearCache(typeURL)
@@ -207,7 +208,7 @@ func main() {
 	// start the xDS server
 	go test.RunAccessLogServer(ctx, als, alsPort)
 	go test.RunManagementServer(ctx, srv, port)
-	go test.RunManagementGateway(ctx, srv, gatewayPort, logger{})
+	go test.RunManagementGateway(ctx, srv, gatewayPort)
 
 	log.Println("waiting for the first request...")
 	select {
@@ -345,25 +346,3 @@ func callEcho() (int, int) {
 		}
 	}
 }
-
-type logger struct{}
-
-func (logger logger) Debugf(format string, args ...interface{}) {
-	if debug {
-		log.Printf(format+"\n", args...)
-	}
-}
-
-func (logger logger) Infof(format string, args ...interface{}) {
-	if debug {
-		log.Printf(format+"\n", args...)
-	}
-}
-
-func (logger logger) Warnf(format string, args ...interface{}) {
-	log.Printf(format+"\n", args...)
-}
-
-func (logger logger) Errorf(format string, args ...interface{}) {
-	log.Printf(format+"\n", args...)
-}

pkg/test/server.go

@@ -94,13 +94,12 @@ func RunManagementServer(ctx context.Context, srv server.Server, port uint) {
 }
 
 // RunManagementGateway starts an HTTP gateway to an xDS server.
-func RunManagementGateway(ctx context.Context, srv server.Server, port uint, lg gcplogger.Logger) {
+func RunManagementGateway(ctx context.Context, srv server.Server, port uint) {
 	log.Printf("gateway listening HTTP/1.1 on %d\n", port)
 	server := &http.Server{
 		Addr: fmt.Sprintf(":%d", port),
 		Handler: &HTTPGateway{
-			Gateway: server.HTTPGateway{Log: lg, Server: srv},
-			Log:     lg,
+			Gateway: server.HTTPGateway{Server: srv},
 		},
 	}
 	go func() {