Infer destination service resource adapt public api

gocontext.go

@@ -90,17 +90,6 @@ func StartSpan(ctx context.Context, name, spanType string) (*Span, context.Conte
 	return StartSpanOptions(ctx, name, spanType, SpanOptions{})
 }
 
-// StartExitSpan starts an exit span. If the provided context already contains
-// an exit span, this function returns a dropped span.
-func StartExitSpan(ctx context.Context, name, spanType string) (*Span, context.Context) {
-	span, ctx := StartSpanOptions(ctx, name, spanType, SpanOptions{})
-	if span.Dropped() {
-		return span, ctx
-	}
-	span.setExitSpan(name, spanType)
-	return span, ctx
-}
-
 // StartSpanOptions starts and returns a new Span within the sampled transaction
 // and parent span in the context, if any. If the span isn't dropped, it will be
 // stored in the resulting context.

model/model.go

@@ -375,7 +375,7 @@ type DestinationServiceSpanContext struct {
 	Type string `json:"type,omitempty"`
 
 	// Name holds the destination service name. Deprecated.
-	Name string `json:"name,omitempty"`
+	Name string `json:"name"`
 
 	// Resource identifies the destination service
 	// resource, e.g. a URI or message queue name.

span.go

@@ -55,17 +55,6 @@ func (tx *Transaction) StartSpan(name, spanType string, parent *Span) *Span {
 	})
 }
 
-// StartExitSpan starts an exit span. If the provided parent is already an exit
-// span, this function returns a dropped span.
-func (tx *Transaction) StartExitSpan(name, spanType string, parent *Span) *Span {
-	span := tx.StartSpan(name, spanType, parent)
-	if span.Dropped() {
-		return span
-	}
-	span.setExitSpan(name, spanType)
-	return span
-}
-
 // StartSpanOptions starts and returns a new Span within the transaction,
 // with the specified name, type, and options.
 //
@@ -77,7 +66,6 @@ func (tx *Transaction) StartExitSpan(name, spanType string, parent *Span) *Span
 // subtype, and the action will not be set.
 func (tx *Transaction) StartSpanOptions(name, spanType string, opts SpanOptions) *Span {
 	if tx == nil || opts.parent.IsExitSpan() {
-		// TODO: Is this the equivalent of a noop span?
 		return newDroppedSpan()
 	}
 
@@ -93,15 +81,20 @@ func (tx *Transaction) StartSpanOptions(name, spanType string, opts SpanOptions)
 	// Lock the parent first to avoid deadlocks in breakdown metrics calculation.
 	if opts.parent != nil {
 		opts.parent.mu.Lock()
-		defer opts.parent.mu.Unlock()
 	}
 
 	// Prevent tx from being ended while we're starting a span.
 	tx.mu.RLock()
 	defer tx.mu.RUnlock()
 	if tx.ended() {
+		if opts.parent != nil {
+			opts.parent.mu.Unlock()
+		}
 		return tx.tracer.StartSpan(name, spanType, transactionID, opts)
 	}
+	if opts.parent != nil {
+		defer opts.parent.mu.Unlock()
+	}
 
 	// Calculate the span time relative to the transaction timestamp so
 	// that wall-clock adjustments occurring after the transaction start
@@ -114,6 +107,9 @@ func (tx *Transaction) StartSpanOptions(name, spanType string, opts SpanOptions)
 	span := tx.tracer.startSpan(name, spanType, transactionID, opts)
 	span.tx = tx
 	span.parent = opts.parent
+	if opts.ExitSpan {
+		span.setExitSpan(name, spanType)
+	}
 
 	// Guard access to spansCreated, spansDropped, rand, and childrenTimer.
 	tx.TransactionData.mu.Lock()
@@ -195,6 +191,10 @@ type SpanOptions struct {
 	// will be generated and used instead.
 	SpanID SpanID
 
+	// Indicates whether a span is an exit span or not. All child spans
+	// will be noop spans.
+	ExitSpan bool
+
 	// parent, if non-nil, holds the parent span.
 	//
 	// This is only used if Parent is zero, and is only available to internal
@@ -255,6 +255,7 @@ type Span struct {
 	traceContext  TraceContext
 	transactionID SpanID
 	parentID      SpanID
+	exit          bool
 
 	mu sync.RWMutex
 
@@ -413,7 +414,12 @@ func (s *Span) setExitSpan(name, spanType string) {
 
 // IsExitSpan returns true if the span is an exit span.
 func (s *Span) IsExitSpan() bool {
-	if s == nil || s.SpanData == nil {
+	if s == nil {
+		return false
+	}
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	if s.SpanData == nil {
 		return false
 	}
 	ctx := s.Context
@@ -432,7 +438,6 @@ type SpanData struct {
 	stackTraceLimit        int
 	timestamp              time.Time
 	childrenTimer          childrenTimer
-	exit                   bool
 
 	// Name holds the span name, initialized with the value passed to StartSpan.
 	Name string

span_test.go

@@ -165,7 +165,7 @@ func TestSpanType(t *testing.T) {
 
 func TestStartExitSpan(t *testing.T) {
 	_, spans, _ := apmtest.WithTransaction(func(ctx context.Context) {
-		span, _ := apm.StartExitSpan(ctx, "name", "type")
+		span, _ := apm.StartSpanOptions(ctx, "name", "type", apm.SpanOptions{ExitSpan: true})
 		assert.True(t, span.IsExitSpan())
 		span.End()
 	})
@@ -176,7 +176,7 @@ func TestStartExitSpan(t *testing.T) {
 	defer tracer.Close()
 
 	tx := tracer.StartTransaction("name", "type")
-	span := tx.StartExitSpan("name", "type", nil)
+	span := tx.StartSpanOptions("name", "type", apm.SpanOptions{ExitSpan: true})
 	assert.True(t, span.IsExitSpan())
 	// when the parent span is an exit span, any children should be noops.
 	span2 := tx.StartSpan("name", "type", span)

spancontext.go

@@ -57,6 +57,10 @@ type DatabaseSpanContext struct {
 
 // DestinationServiceSpanContext holds destination service span span.
 type DestinationServiceSpanContext struct {
+	// Name holds a name for the destination service, which may be used
+	// for grouping and labeling in service maps. Deprecated.
+	Name string
+
 	// Resource holds an identifier for a destination service resource,
 	// such as a message queue.
 	Resource string
@@ -220,6 +224,7 @@ func (c *SpanContext) SetDestinationService(service DestinationServiceSpanContex
 	if service.Resource == "" {
 		return
 	}
+	c.destinationService.Name = truncateString(service.Name)
 	c.destinationService.Resource = truncateString(service.Resource)
 	c.destination.Service = &c.destinationService
 	c.model.Destination = &c.destination

validation_test.go

@@ -119,11 +119,12 @@ func TestValidateDatabaseSpanContext(t *testing.T) {
 
 func TestValidateDestinationSpanContext(t *testing.T) {
 	overlong := strings.Repeat("x", 1025)
-	for range []string{"", overlong} {
+	for _, name := range []string{"", overlong} {
 		for _, resource := range []string{"", overlong} {
 			validateSpan(t, func(s *apm.Span) {
 				s.Context.SetDestinationAddress(overlong, 0)
 				s.Context.SetDestinationService(apm.DestinationServiceSpanContext{
+					Name:     name,
 					Resource: resource,
 				})
 			})