Drop SetAttribute from Span (#361)

fixes #302

api/testharness/harness.go

@@ -310,9 +310,6 @@ func (h *Harness) testSpan(tracerFactory func() trace.Tracer) {
 		"#SetName": func(span trace.Span) {
 			span.SetName("new name")
 		},
-		"#SetAttribute": func(span trace.Span) {
-			span.SetAttribute(core.Key("key").String("value"))
-		},
 		"#SetAttributes": func(span trace.Span) {
 			span.SetAttributes(core.Key("key1").String("value"), core.Key("key2").Int(123))
 		},

api/trace/api.go

@@ -84,7 +84,6 @@ type Span interface {
 	SetName(name string)
 
 	// Set span attributes
-	SetAttribute(core.KeyValue)
 	SetAttributes(...core.KeyValue)
 }
 

api/trace/current_test.go

@@ -79,10 +79,6 @@ func (mockSpan) SetName(name string) {
 func (mockSpan) SetError(v bool) {
 }
 
-// SetAttribute does nothing.
-func (mockSpan) SetAttribute(attribute core.KeyValue) {
-}
-
 // SetAttributes does nothing.
 func (mockSpan) SetAttributes(attributes ...core.KeyValue) {
 }

api/trace/noop_span.go

@@ -46,10 +46,6 @@ func (NoopSpan) SetStatus(status codes.Code) {
 func (NoopSpan) SetError(v bool) {
 }
 
-// SetAttribute does nothing.
-func (NoopSpan) SetAttribute(attribute core.KeyValue) {
-}
-
 // SetAttributes does nothing.
 func (NoopSpan) SetAttributes(attributes ...core.KeyValue) {
 }

bridge/opentracing/bridge.go

@@ -131,7 +131,7 @@ func (s *bridgeSpan) SetTag(key string, value interface{}) ot.Span {
 			s.otelSpan.SetStatus(status)
 		}
 	default:
-		s.otelSpan.SetAttribute(otTagToOtelCoreKeyValue(key, value))
+		s.otelSpan.SetAttributes(otTagToOtelCoreKeyValue(key, value))
 	}
 	return s
 }

bridge/opentracing/internal/mock.go

@@ -225,21 +225,15 @@ func (s *MockSpan) IsRecording() bool {
 }
 
 func (s *MockSpan) SetStatus(status codes.Code) {
-	s.SetAttribute(NameKey.Uint32(uint32(status)))
+	s.SetAttributes(NameKey.Uint32(uint32(status)))
 }
 
 func (s *MockSpan) SetName(name string) {
-	s.SetAttribute(NameKey.String(name))
+	s.SetAttributes(NameKey.String(name))
 }
 
 func (s *MockSpan) SetError(v bool) {
-	s.SetAttribute(ErrorKey.Bool(v))
+	s.SetAttributes(ErrorKey.Bool(v))
-}
-
-func (s *MockSpan) SetAttribute(attribute otelcore.KeyValue) {
-	s.applyUpdate(oteldctx.MapUpdate{
-		SingleKV: attribute,
-	})
 }
 
 func (s *MockSpan) SetAttributes(attributes ...otelcore.KeyValue) {

example/basic/main.go

@@ -126,7 +126,7 @@ func main() {
 			ctx,
 			"Sub operation...",
 			func(ctx context.Context) error {
-				trace.CurrentSpan(ctx).SetAttribute(lemonsKey.String("five"))
+				trace.CurrentSpan(ctx).SetAttributes(lemonsKey.String("five"))
 
 				trace.CurrentSpan(ctx).AddEvent(ctx, "Sub span event")
 

example/namedtracer/foo/foo.go

@@ -37,7 +37,7 @@ func SubOperation(ctx context.Context) error {
 		ctx,
 		"Sub operation...",
 		func(ctx context.Context) error {
-			trace.CurrentSpan(ctx).SetAttribute(lemonsKey.String("five"))
+			trace.CurrentSpan(ctx).SetAttributes(lemonsKey.String("five"))
 
 			trace.CurrentSpan(ctx).AddEvent(ctx, "Sub span event")
 

exporter/trace/stackdriver/trace.go

@@ -83,7 +83,7 @@ func (e *traceExporter) uploadSpans(ctx context.Context, spans []*tracepb.Span)
 	// 	"go.opentelemetry.io/otel/exporter/stackdriver.uploadSpans",
 	// )
 	// defer span.End()
-	// span.SetAttribute(key.New("num_spans").Int64(int64(len(spans))))
+	// span.SetAttributes(key.New("num_spans").Int64(int64(len(spans))))
 
 	err := e.client.BatchWriteSpans(ctx, &req)
 	if err != nil {

internal/trace/mock_span.go

@@ -54,10 +54,6 @@ func (ms *MockSpan) SetStatus(status codes.Code) {
 func (ms *MockSpan) SetError(v bool) {
 }
 
-// SetAttribute does nothing.
-func (ms *MockSpan) SetAttribute(attribute core.KeyValue) {
-}
-
 // SetAttributes does nothing.
 func (ms *MockSpan) SetAttributes(attributes ...core.KeyValue) {
 }

plugin/httptrace/clienttrace.go

@@ -99,7 +99,7 @@ func (ct *clientTracer) end(hook string, err error, attrs ...core.KeyValue) {
 	if span, ok := ct.activeHooks[hook]; ok {
 		if err != nil {
 			span.SetStatus(codes.Unknown)
-			span.SetAttribute(MessageKey.String(err.Error()))
+			span.SetAttributes(MessageKey.String(err.Error()))
 		}
 		span.SetAttributes(attrs...)
 		span.End()
@@ -164,7 +164,7 @@ func (ct *clientTracer) wroteHeaderField(k string, v []string) {
 	if ct.span("http.headers") == nil {
 		ct.start("http.headers", "http.headers")
 	}
-	ct.root.SetAttribute(key.String("http."+strings.ToLower(k), sliceToString(v)))
+	ct.root.SetAttributes(key.String("http."+strings.ToLower(k), sliceToString(v)))
 }
 
 func (ct *clientTracer) wroteHeaders() {
@@ -173,7 +173,7 @@ func (ct *clientTracer) wroteHeaders() {
 
 func (ct *clientTracer) wroteRequest(info httptrace.WroteRequestInfo) {
 	if info.Err != nil {
-		ct.root.SetAttribute(MessageKey.String(info.Err.Error()))
+		ct.root.SetAttributes(MessageKey.String(info.Err.Error()))
 		ct.root.SetStatus(codes.Unknown)
 	}
 	ct.end("http.send", info.Err)

plugin/othttp/handler.go

@@ -223,7 +223,7 @@ func WithRouteTag(route string, h http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		span := trace.CurrentSpan(r.Context())
 		//TODO: Why doesn't tag.Upsert work?
-		span.SetAttribute(RouteKey.String(route))
+		span.SetAttributes(RouteKey.String(route))
 		h.ServeHTTP(w, r.WithContext(trace.SetCurrentSpan(r.Context(), span)))
 	})
 }

plugin/othttp/handler_example_test.go

@@ -65,7 +65,7 @@ func ExampleNewHandler() {
 		case "":
 			err = fmt.Errorf("expected /hello/:name in %q", s)
 		default:
-			trace.CurrentSpan(ctx).SetAttribute(core.Key("name").String(pp[1]))
+			trace.CurrentSpan(ctx).SetAttributes(core.Key("name").String(pp[1]))
 		}
 		return pp[1], err
 	}

sdk/trace/benchmark_test.go

@@ -53,39 +53,6 @@ func BenchmarkSpanWithAttributes_4(b *testing.B) {
 	})
 }
 
-func BenchmarkSpan_SetAttributes(b *testing.B) {
-	b.Run("SetAttribute", func(b *testing.B) {
-		traceBenchmark(b, "Benchmark Start With 4 Attributes", func(b *testing.B, t apitrace.Tracer) {
-			ctx := context.Background()
-			b.ResetTimer()
-
-			for i := 0; i < b.N; i++ {
-				_, span := t.Start(ctx, "/foo")
-				span.SetAttribute(key.New("key1").Bool(false))
-				span.SetAttribute(key.New("key2").String("hello"))
-				span.SetAttribute(key.New("key3").Uint64(123))
-				span.SetAttribute(key.New("key4").Float64(123.456))
-				span.End()
-			}
-		})
-	})
-
-	b.Run("SetAttributes", func(b *testing.B) {
-		traceBenchmark(b, "Benchmark Start With 4 Attributes", func(b *testing.B, t apitrace.Tracer) {
-			ctx := context.Background()
-			b.ResetTimer()
-			for i := 0; i < b.N; i++ {
-				_, span := t.Start(ctx, "/foo")
-				span.SetAttributes(key.New("key1").Bool(false))
-				span.SetAttributes(key.New("key2").String("hello"))
-				span.SetAttributes(key.New("key3").Uint64(123))
-				span.SetAttributes(key.New("key4").Float64(123.456))
-				span.End()
-			}
-		})
-	})
-}
-
 func BenchmarkSpanWithAttributes_8(b *testing.B) {
 	traceBenchmark(b, "Benchmark Start With 8 Attributes", func(b *testing.B, t apitrace.Tracer) {
 		ctx := context.Background()

sdk/trace/span.go

@@ -84,13 +84,6 @@ func (s *span) SetStatus(status codes.Code) {
 	s.mu.Unlock()
 }
 
-func (s *span) SetAttribute(attribute core.KeyValue) {
-	if !s.IsRecording() {
-		return
-	}
-	s.copyToCappedAttributes(attribute)
-}
-
 func (s *span) SetAttributes(attributes ...core.KeyValue) {
 	if !s.IsRecording() {
 		return

sdk/trace/trace_test.go

@@ -328,7 +328,7 @@ func TestSetSpanAttributes(t *testing.T) {
 	te := &testExporter{}
 	tp, _ := NewProvider(WithSyncer(te))
 	span := startSpan(tp, "SpanAttribute")
-	span.SetAttribute(key.New("key1").String("value1"))
+	span.SetAttributes(key.New("key1").String("value1"))
 	got, err := endSpan(te, span)
 	if err != nil {
 		t.Fatal(err)
@@ -358,10 +358,12 @@ func TestSetSpanAttributesOverLimit(t *testing.T) {
 	tp, _ := NewProvider(WithConfig(cfg), WithSyncer(te))
 
 	span := startSpan(tp, "SpanAttributesOverLimit")
-	span.SetAttribute(key.Bool("key1", true))
+	span.SetAttributes(
-	span.SetAttribute(key.String("key2", "value2"))
+		key.Bool("key1", true),
-	span.SetAttribute(key.Bool("key1", false)) // Replace key1.
+		key.String("key2", "value2"),
-	span.SetAttribute(key.Int64("key4", 4))    // Remove key2 and add key4
+		key.Bool("key1", false), // Replace key1.
+		key.Int64("key4", 4),    // Remove key2 and add key4
+	)
 	got, err := endSpan(te, span)
 	if err != nil {
 		t.Fatal(err)