add ability to skip endpoints for tracer and meter

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

meter/meter.go

@@ -24,6 +24,13 @@ var (
 	DefaultSummaryQuantiles = []float64{0.5, 0.9, 0.97, 0.99, 1}
 	// DefaultSummaryWindow is the default window for summary
 	DefaultSummaryWindow = 5 * time.Minute
+	// DefaultSkipEndpoints is the slice of endpoint that must not be metered
+	DefaultSkipEndpoints = []string{
+		"MeterService.Metrics",
+		"HealthService.Live",
+		"HealthService.Ready",
+		"HealthService.Version",
+	}
 )
 
 // Meter is an interface for collecting and instrumenting metrics

server/noop.go

@@ -274,7 +274,7 @@ func (n *noopServer) Register() error {
 
 	if !registered {
 		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Infof(n.opts.Context, "register [%s] Registering node: %s", config.Register.String(), service.Nodes[0].ID)
+			config.Logger.Info(n.opts.Context, fmt.Sprintf("register [%s] Registering node: %s", config.Register.String(), service.Nodes[0].ID))
 		}
 	}
 
@@ -312,7 +312,7 @@ func (n *noopServer) Deregister() error {
 	}
 
 	if config.Logger.V(logger.InfoLevel) {
-		config.Logger.Infof(n.opts.Context, "deregistering node: %s", service.Nodes[0].ID)
+		config.Logger.Info(n.opts.Context, fmt.Sprintf("deregistering node: %s", service.Nodes[0].ID))
 	}
 
 	if err := DefaultDeregisterFunc(service, config); err != nil {
@@ -343,11 +343,11 @@ func (n *noopServer) Deregister() error {
 			go func(s broker.Subscriber) {
 				defer wg.Done()
 				if config.Logger.V(logger.InfoLevel) {
-					config.Logger.Infof(n.opts.Context, "unsubscribing from topic: %s", s.Topic())
+					config.Logger.Info(n.opts.Context, "unsubscribing from topic: "+s.Topic())
 				}
 				if err := s.Unsubscribe(ncx); err != nil {
 					if config.Logger.V(logger.ErrorLevel) {
-						config.Logger.Errorf(n.opts.Context, "unsubscribing from topic: %s err: %v", s.Topic(), err)
+						config.Logger.Error(n.opts.Context, "unsubscribing from topic: "+s.Topic(), err)
 					}
 				}
 			}(subs[idx])
@@ -383,7 +383,7 @@ func (n *noopServer) Start() error {
 	config.Address = addr
 
 	if config.Logger.V(logger.InfoLevel) {
-		config.Logger.Infof(n.opts.Context, "server [noop] Listening on %s", config.Address)
+		config.Logger.Info(n.opts.Context, "server [noop] Listening on "+config.Address)
 	}
 
 	n.Lock()
@@ -397,13 +397,13 @@ func (n *noopServer) Start() error {
 		// connect to the broker
 		if err := config.Broker.Connect(config.Context); err != nil {
 			if config.Logger.V(logger.ErrorLevel) {
-				config.Logger.Errorf(n.opts.Context, "broker [%s] connect error: %v", config.Broker.String(), err)
+				config.Logger.Error(n.opts.Context, fmt.Sprintf("broker [%s] connect error", config.Broker.String()), err)
 			}
 			return err
 		}
 
 		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Infof(n.opts.Context, "broker [%s] Connected to %s", config.Broker.String(), config.Broker.Address())
+			config.Logger.Info(n.opts.Context, fmt.Sprintf("broker [%s] Connected to %s", config.Broker.String(), config.Broker.Address()))
 		}
 	}
 
@@ -411,13 +411,13 @@ func (n *noopServer) Start() error {
 	// nolint: nestif
 	if err := config.RegisterCheck(config.Context); err != nil {
 		if config.Logger.V(logger.ErrorLevel) {
-			config.Logger.Errorf(n.opts.Context, "server %s-%s register check error: %s", config.Name, config.ID, err)
+			config.Logger.Error(n.opts.Context, fmt.Sprintf("server %s-%s register check error", config.Name, config.ID), err)
 		}
 	} else {
 		// announce self to the world
 		if err := n.Register(); err != nil {
 			if config.Logger.V(logger.ErrorLevel) {
-				config.Logger.Errorf(n.opts.Context, "server register error: %v", err)
+				config.Logger.Error(n.opts.Context, "server register error", err)
 			}
 		}
 	}
@@ -450,23 +450,23 @@ func (n *noopServer) Start() error {
 				// nolint: nestif
 				if rerr != nil && registered {
 					if config.Logger.V(logger.ErrorLevel) {
-						config.Logger.Errorf(n.opts.Context, "server %s-%s register check error: %s, deregister it", config.Name, config.ID, rerr)
+						config.Logger.Error(n.opts.Context, fmt.Sprintf("server %s-%s register check error, deregister it", config.Name, config.ID), rerr)
 					}
 					// deregister self in case of error
 					if err := n.Deregister(); err != nil {
 						if config.Logger.V(logger.ErrorLevel) {
-							config.Logger.Errorf(n.opts.Context, "server %s-%s deregister error: %s", config.Name, config.ID, err)
+							config.Logger.Error(n.opts.Context, fmt.Sprintf("server %s-%s deregister error", config.Name, config.ID), err)
 						}
 					}
 				} else if rerr != nil && !registered {
 					if config.Logger.V(logger.ErrorLevel) {
-						config.Logger.Errorf(n.opts.Context, "server %s-%s register check error: %s", config.Name, config.ID, rerr)
+						config.Logger.Errorf(n.opts.Context, fmt.Sprintf("server %s-%s register check error", config.Name, config.ID), rerr)
 					}
 					continue
 				}
 				if err := n.Register(); err != nil {
 					if config.Logger.V(logger.ErrorLevel) {
-						config.Logger.Errorf(n.opts.Context, "server %s-%s register error: %s", config.Name, config.ID, err)
+						config.Logger.Error(n.opts.Context, fmt.Sprintf("server %s-%s register error", config.Name, config.ID), err)
 					}
 				}
 			// wait for exit
@@ -478,7 +478,7 @@ func (n *noopServer) Start() error {
 		// deregister self
 		if err := n.Deregister(); err != nil {
 			if config.Logger.V(logger.ErrorLevel) {
-				config.Logger.Errorf(n.opts.Context, "server deregister error: ", err)
+				config.Logger.Error(n.opts.Context, "server deregister error", err)
 			}
 		}
 
@@ -491,12 +491,12 @@ func (n *noopServer) Start() error {
 		ch <- nil
 
 		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Infof(n.opts.Context, "broker [%s] Disconnected from %s", config.Broker.String(), config.Broker.Address())
+			config.Logger.Info(n.opts.Context, fmt.Sprintf("broker [%s] Disconnected from %s", config.Broker.String(), config.Broker.Address()))
 		}
 		// disconnect broker
 		if err := config.Broker.Disconnect(config.Context); err != nil {
 			if config.Logger.V(logger.ErrorLevel) {
-				config.Logger.Errorf(n.opts.Context, "broker [%s] disconnect error: %v", config.Broker.String(), err)
+				config.Logger.Error(n.opts.Context, fmt.Sprintf("broker [%s] disconnect error", config.Broker.String()), err)
 			}
 		}
 	}()
@@ -512,36 +512,33 @@ func (n *noopServer) Start() error {
 func (n *noopServer) subscribe() error {
 	config := n.Options()
 
-	cx := config.Context
-	var err error
-	var sub broker.Subscriber
+	subCtx := config.Context
 
 	for sb := range n.subscribers {
-		if sb.Options().Context != nil {
-			cx = sb.Options().Context
+
+		if cx := sb.Options().Context; cx != nil {
+			subCtx = cx
+		}
+
+		opts := []broker.SubscribeOption{
+			broker.SubscribeContext(subCtx),
+			broker.SubscribeAutoAck(sb.Options().AutoAck),
+			broker.SubscribeBodyOnly(sb.Options().BodyOnly),
 		}
 
-		opts := []broker.SubscribeOption{broker.SubscribeContext(cx), broker.SubscribeAutoAck(sb.Options().AutoAck)}
 		if queue := sb.Options().Queue; len(queue) > 0 {
 			opts = append(opts, broker.SubscribeGroup(queue))
 		}
 
-		if sb.Options().Batch {
-			// batch processing handler
-			sub, err = config.Broker.BatchSubscribe(cx, sb.Topic(), n.createBatchSubHandler(sb, config), opts...)
-		} else {
-			// single processing handler
-			sub, err = config.Broker.Subscribe(cx, sb.Topic(), n.createSubHandler(sb, config), opts...)
+		if config.Logger.V(logger.InfoLevel) {
+			config.Logger.Info(n.opts.Context, "subscribing to topic: "+sb.Topic())
 		}
 
+		sub, err := config.Broker.Subscribe(subCtx, sb.Topic(), n.createSubHandler(sb, config), opts...)
 		if err != nil {
 			return err
 		}
 
-		if config.Logger.V(logger.InfoLevel) {
-			config.Logger.Infof(n.opts.Context, "subscribing to topic: %s", sb.Topic())
-		}
-
 		n.subscribers[sb] = []broker.Subscriber{sub}
 	}
 
@@ -637,127 +634,6 @@ func newSubscriber(topic string, sub interface{}, opts ...SubscriberOption) Subs
 	}
 }
 
-//nolint:gocyclo
-func (n *noopServer) createBatchSubHandler(sb *subscriber, opts Options) broker.BatchHandler {
-	return func(ps broker.Events) (err error) {
-		defer func() {
-			if r := recover(); r != nil {
-				n.RLock()
-				config := n.opts
-				n.RUnlock()
-				if config.Logger.V(logger.ErrorLevel) {
-					config.Logger.Error(n.opts.Context, "panic recovered: ", r)
-					config.Logger.Error(n.opts.Context, string(debug.Stack()))
-				}
-				err = errors.InternalServerError(n.opts.Name+".subscriber", "panic recovered: %v", r)
-			}
-		}()
-
-		msgs := make([]Message, 0, len(ps))
-		ctxs := make([]context.Context, 0, len(ps))
-		for _, p := range ps {
-			msg := p.Message()
-			// if we don't have headers, create empty map
-			if msg.Header == nil {
-				msg.Header = metadata.New(2)
-			}
-
-			ct, _ := msg.Header.Get(metadata.HeaderContentType)
-			if len(ct) == 0 {
-				msg.Header.Set(metadata.HeaderContentType, defaultContentType)
-				ct = defaultContentType
-			}
-			hdr := metadata.Copy(msg.Header)
-			topic, _ := msg.Header.Get(metadata.HeaderTopic)
-			ctxs = append(ctxs, metadata.NewIncomingContext(sb.opts.Context, hdr))
-			msgs = append(msgs, &rpcMessage{
-				topic:       topic,
-				contentType: ct,
-				header:      msg.Header,
-				body:        msg.Body,
-			})
-		}
-		results := make(chan error, len(sb.handlers))
-
-		for i := 0; i < len(sb.handlers); i++ {
-			handler := sb.handlers[i]
-
-			var req reflect.Value
-
-			switch handler.reqType.Kind() {
-			case reflect.Ptr:
-				req = reflect.New(handler.reqType.Elem())
-			default:
-				req = reflect.New(handler.reqType.Elem()).Elem()
-			}
-
-			reqType := handler.reqType
-			var cf codec.Codec
-			for _, msg := range msgs {
-				cf, err = n.newCodec(msg.ContentType())
-				if err != nil {
-					return err
-				}
-				rb := reflect.New(req.Type().Elem())
-				if err = cf.ReadBody(bytes.NewReader(msg.(*rpcMessage).body), rb.Interface()); err != nil {
-					return err
-				}
-				msg.(*rpcMessage).codec = cf
-				msg.(*rpcMessage).payload = rb.Interface()
-			}
-
-			fn := func(ctxs []context.Context, ms []Message) error {
-				var vals []reflect.Value
-				if sb.typ.Kind() != reflect.Func {
-					vals = append(vals, sb.rcvr)
-				}
-				if handler.ctxType != nil {
-					vals = append(vals, reflect.ValueOf(ctxs))
-				}
-				payloads := reflect.MakeSlice(reqType, 0, len(ms))
-				for _, m := range ms {
-					payloads = reflect.Append(payloads, reflect.ValueOf(m.Body()))
-				}
-				vals = append(vals, payloads)
-
-				returnValues := handler.method.Call(vals)
-				if rerr := returnValues[0].Interface(); rerr != nil {
-					return rerr.(error)
-				}
-				return nil
-			}
-
-			opts.Hooks.EachNext(func(hook options.Hook) {
-				if h, ok := hook.(HookBatchSubHandler); ok {
-					fn = h(fn)
-				}
-			})
-
-			if n.wg != nil {
-				n.wg.Add(1)
-			}
-
-			go func() {
-				if n.wg != nil {
-					defer n.wg.Done()
-				}
-				results <- fn(ctxs, msgs)
-			}()
-		}
-
-		var errors []string
-		for i := 0; i < len(sb.handlers); i++ {
-			if rerr := <-results; rerr != nil {
-				errors = append(errors, rerr.Error())
-			}
-		}
-		if len(errors) > 0 {
-			err = fmt.Errorf("subscriber error: %s", strings.Join(errors, "\n"))
-		}
-		return err
-	}
-}
-
 //nolint:gocyclo
 func (n *noopServer) createSubHandler(sb *subscriber, opts Options) broker.Handler {
 	return func(p broker.Event) (err error) {

server/noop_test.go

@@ -9,7 +9,6 @@ import (
 	"go.unistack.org/micro/v3/client"
 	"go.unistack.org/micro/v3/codec"
 	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
 	"go.unistack.org/micro/v3/server"
 )
 
@@ -26,18 +25,6 @@ func (h *TestHandler) SingleSubHandler(ctx context.Context, msg *codec.Frame) er
 	return nil
 }
 
-func (h *TestHandler) BatchSubHandler(ctxs []context.Context, msgs []*codec.Frame) error {
-	if len(msgs) != 8 {
-		h.t.Fatal("invalid number of messages received")
-	}
-	for idx := 0; idx < len(msgs); idx++ {
-		md, _ := metadata.FromIncomingContext(ctxs[idx])
-		_ = md
-		//	fmt.Printf("msg md %v\n", md)
-	}
-	return nil
-}
-
 func TestNoopSub(t *testing.T) {
 	ctx := context.Background()
 
@@ -76,13 +63,6 @@ func TestNoopSub(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if err := s.Subscribe(s.NewSubscriber("batch_topic", h.BatchSubHandler,
-		server.SubscriberQueue("queue"),
-		server.SubscriberBatch(true),
-	)); err != nil {
-		t.Fatal(err)
-	}
-
 	if err := s.Start(); err != nil {
 		t.Fatal(err)
 	}

server/options.go

@@ -341,8 +341,6 @@ type SubscriberOptions struct {
 	AutoAck bool
 	// BodyOnly flag specifies that message without headers
 	BodyOnly bool
-	// Batch flag specifies that message processed in batches
-	Batch bool
 	// BatchSize flag specifies max size of batch
 	BatchSize int
 	// BatchWait flag specifies max wait time for batch filling
@@ -414,13 +412,6 @@ func SubscriberAck(b bool) SubscriberOption {
 	}
 }
 
-// SubscriberBatch control batch processing for handler
-func SubscriberBatch(b bool) SubscriberOption {
-	return func(o *SubscriberOptions) {
-		o.Batch = b
-	}
-}
-
 // SubscriberBatchSize control batch filling size for handler
 // Batch filling max waiting time controlled by SubscriberBatchWait
 func SubscriberBatchSize(n int) SubscriberOption {

server/server.go

@@ -63,10 +63,10 @@ type Server interface {
 }
 
 type (
-	FuncBatchSubHandler func(ctxs []context.Context, ms []Message) error
-	HookBatchSubHandler func(next FuncBatchSubHandler) FuncBatchSubHandler
 	FuncSubHandler func(ctx context.Context, ms Message) error
 	HookSubHandler func(next FuncSubHandler) FuncSubHandler
+	FuncHandler    func(ctx context.Context, req Request, rsp interface{}) error
+	HookHandler    func(next FuncHandler) FuncHandler
 )
 
 /*

server/subscriber.go

@@ -3,14 +3,12 @@ package server
 import (
 	"fmt"
 	"reflect"
-	"strings"
 	"unicode"
 	"unicode/utf8"
 )
 
 const (
 	subSig = "func(context.Context, interface{}) error"
-	batchSubSig = "func([]context.Context, []interface{}) error"
 )
 
 // Precompute the reflect type for error. Can't use error directly
@@ -43,23 +41,15 @@ func ValidateSubscriber(sub Subscriber) error {
 		switch typ.NumIn() {
 		case 2:
 			argType = typ.In(1)
-			if sub.Options().Batch {
-				if argType.Kind() != reflect.Slice {
-					return fmt.Errorf("subscriber %v dont have required signature %s", name, batchSubSig)
-				}
-				if strings.Compare(fmt.Sprintf("%v", argType), "[]interface{}") == 0 {
-					return fmt.Errorf("subscriber %v dont have required signaure %s", name, batchSubSig)
-				}
-			}
 		default:
-			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s or %s", name, typ.NumIn(), subSig, batchSubSig)
+			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s", name, typ.NumIn(), subSig)
 		}
 		if !isExportedOrBuiltinType(argType) {
 			return fmt.Errorf("subscriber %v argument type not exported: %v", name, argType)
 		}
 		if typ.NumOut() != 1 {
-			return fmt.Errorf("subscriber %v has wrong number of return values: %v require signature %s or %s",
-				name, typ.NumOut(), subSig, batchSubSig)
+			return fmt.Errorf("subscriber %v has wrong number of return values: %v require signature %s",
+				name, typ.NumOut(), subSig)
 		}
 		if returnType := typ.Out(0); returnType != typeOfError {
 			return fmt.Errorf("subscriber %v returns %v not error", name, returnType.String())
@@ -74,8 +64,8 @@ func ValidateSubscriber(sub Subscriber) error {
 			case 3:
 				argType = method.Type.In(2)
 			default:
-				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s or %s",
-					name, method.Name, method.Type.NumIn(), subSig, batchSubSig)
+				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s",
+					name, method.Name, method.Type.NumIn(), subSig)
 			}
 
 			if !isExportedOrBuiltinType(argType) {
@@ -83,8 +73,8 @@ func ValidateSubscriber(sub Subscriber) error {
 			}
 			if method.Type.NumOut() != 1 {
 				return fmt.Errorf(
-					"subscriber %v.%v has wrong number of return values: %v require signature %s or %s",
-					name, method.Name, method.Type.NumOut(), subSig, batchSubSig)
+					"subscriber %v.%v has wrong number of return values: %v require signature %s",
+					name, method.Name, method.Type.NumOut(), subSig)
 			}
 			if returnType := method.Type.Out(0); returnType != typeOfError {
 				return fmt.Errorf("subscriber %v.%v returns %v not error", name, method.Name, returnType.String())

server/wrapper.go

@@ -14,20 +14,12 @@ type HandlerFunc func(ctx context.Context, req Request, rsp interface{}) error
 // publication message.
 type SubscriberFunc func(ctx context.Context, msg Message) error
 
-// BatchSubscriberFunc represents a single method of a subscriber. It's used primarily
-// for the wrappers. What's handed to the actual method is the concrete
-// publication message. This func used by batch subscribers
-type BatchSubscriberFunc func(ctxs []context.Context, msgs []Message) error
-
 // HandlerWrapper wraps the HandlerFunc and returns the equivalent
 type HandlerWrapper func(HandlerFunc) HandlerFunc
 
 // SubscriberWrapper wraps the SubscriberFunc and returns the equivalent
 type SubscriberWrapper func(SubscriberFunc) SubscriberFunc
 
-// BatchSubscriberWrapper wraps the SubscriberFunc and returns the equivalent
-type BatchSubscriberWrapper func(BatchSubscriberFunc) BatchSubscriberFunc
-
 // StreamWrapper wraps a Stream interface and returns the equivalent.
 // Because streams exist for the lifetime of a method invocation this
 // is a convenient way to wrap a Stream as its in use for trace, monitoring,

tracer/tracer.go

@@ -7,14 +7,20 @@ import (
 	"go.unistack.org/micro/v3/logger"
 )
 
-// DefaultTracer is the global default tracer
-var DefaultTracer Tracer = NewTracer()
-
 var (
+	// DefaultTracer is the global default tracer
+	DefaultTracer Tracer = NewTracer() //nolint:revive
 	// TraceIDKey is the key used for the trace id in the log call
 	TraceIDKey = "trace-id"
 	// SpanIDKey is the key used for the span id in the log call
 	SpanIDKey = "span-id"
+	// DefaultSkipEndpoints is the slice of endpoint that must not be traced
+	DefaultSkipEndpoints = []string{
+		"MeterService.Metrics",
+		"HealthService.Live",
+		"HealthService.Ready",
+		"HealthService.Version",
+	}
 )
 
 func init() {

util/reflect/struct.go

@@ -25,6 +25,48 @@ type StructField struct {
 	Field reflect.StructField
 }
 
+// StructFieldNameByTag get struct field name by tag key and its value
+func StructFieldNameByTag(src interface{}, tkey string, tval string) (string, interface{}, error) {
+	sv := reflect.ValueOf(src)
+	if sv.Kind() == reflect.Ptr {
+		sv = sv.Elem()
+	}
+	if sv.Kind() != reflect.Struct {
+		return "", nil, ErrInvalidStruct
+	}
+
+	typ := sv.Type()
+	for idx := 0; idx < typ.NumField(); idx++ {
+		fld := typ.Field(idx)
+		val := sv.Field(idx)
+		if len(fld.PkgPath) != 0 {
+			continue
+		}
+
+		if ts, ok := fld.Tag.Lookup(tkey); ok {
+			for _, p := range strings.Split(ts, ",") {
+				if p == tval {
+					return fld.Name, val.Interface(), nil
+				}
+			}
+		}
+
+		switch val.Kind() {
+		case reflect.Ptr:
+			if val = val.Elem(); val.Kind() == reflect.Struct {
+				if name, fld, err := StructFieldNameByTag(val.Interface(), tkey, tval); err == nil {
+					return name, fld, nil
+				}
+			}
+		case reflect.Struct:
+			if name, fld, err := StructFieldNameByTag(val.Interface(), tkey, tval); err == nil {
+				return name, fld, nil
+			}
+		}
+	}
+	return "", nil, ErrNotFound
+}
+
 // StructFieldByTag get struct field by tag key and its value
 func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, error) {
 	sv := reflect.ValueOf(src)
@@ -46,9 +88,6 @@ func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, e
 		if ts, ok := fld.Tag.Lookup(tkey); ok {
 			for _, p := range strings.Split(ts, ",") {
 				if p == tval {
-					if val.Kind() != reflect.Ptr && val.CanAddr() {
-						val = val.Addr()
-					}
 					return val.Interface(), nil
 				}
 			}
@@ -72,10 +111,21 @@ func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, e
 
 // ZeroFieldByPath clean struct field by its path
 func ZeroFieldByPath(src interface{}, path string) error {
+	if src == nil {
+		return nil
+	}
 	var err error
 	val := reflect.ValueOf(src)
 
+	if IsEmpty(val) {
+		return nil
+	}
+
 	for _, p := range strings.Split(path, ".") {
+		if IsEmpty(val) {
+			return nil
+		}
+
 		val, err = structValueByName(val, p)
 		if err != nil {
 			return err
@@ -493,6 +543,7 @@ func btSplitter(str string) []string {
 }
 
 // queryToMap turns something like a[b][c]=4 into
+//
 //	  map[string]interface{}{
 //	    "a": map[string]interface{}{
 //			  "b": map[string]interface{}{

util/reflect/struct_test.go

@@ -190,9 +190,9 @@ func TestStructFieldByTag(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if v, ok := iface.(*[]string); !ok {
+	if v, ok := iface.([]string); !ok {
 		t.Fatalf("not *[]string %v", iface)
-	} else if len(*v) != 2 {
+	} else if len(v) != 2 {
 		t.Fatalf("invalid number %v", iface)
 	}
 }