feat(span): remove SetAttribute method (#1216)

* feat(span): remove SetAttribute method

* Update CHANGELOG.md

Revert markdown lint changes and unify the `Removed` section.

Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>

CHANGELOG.md

@@ -23,9 +23,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - The `ExtractHTTP` and `InjectHTTP` fuctions from the `go.opentelemetry.io/otel/api/propagation` package were removed. (#1212)
 - The `Propagators` interface from the `go.opentelemetry.io/otel/api/propagation` package was removed to conform to the OpenTelemetry specification.
    The explicit `TextMapPropagator` type can be used in its place as this is the `Propagator` type the specification defines. (#1212)
-
-### Removed
-
+- The `SetAttribute` method of the `Span` from the `go.opentelemetry.io/otel/api/trace` package was removed given its redundancy with the `SetAttributes` method. (#1216)
 - Remove duplicate hostname key `HostHostNameKey` in Resource semantic conventions. (#1219)
 
 ## [0.12.0] - 2020-09-24

api/trace/api.go

@@ -138,9 +138,6 @@ type Span interface {
 
 	// Set span attributes
 	SetAttributes(kv ...label.KeyValue)
-
-	// Set singular span attribute, with type inference.
-	SetAttribute(k string, v interface{})
 }
 
 // SpanConfig is a group of options for a Span.

api/trace/context_test.go

@@ -96,10 +96,6 @@ func (mockSpan) SetError(v bool) {
 func (mockSpan) SetAttributes(attributes ...label.KeyValue) {
 }
 
-// SetAttribute does nothing.
-func (mockSpan) SetAttribute(k string, v interface{}) {
-}
-
 // End does nothing.
 func (mockSpan) End(options ...trace.SpanOption) {
 }

api/trace/noop_span.go

@@ -49,10 +49,6 @@ func (noopSpan) SetError(v bool) {
 func (noopSpan) SetAttributes(attributes ...label.KeyValue) {
 }
 
-// SetAttribute does nothing.
-func (noopSpan) SetAttribute(k string, v interface{}) {
-}
-
 // End does nothing.
 func (noopSpan) End(options ...SpanOption) {
 }

api/trace/tracetest/mock_span.go

@@ -62,10 +62,6 @@ func (ms *MockSpan) SetError(v bool) {
 func (ms *MockSpan) SetAttributes(attributes ...label.KeyValue) {
 }
 
-// SetAttribute does nothing.
-func (ms *MockSpan) SetAttribute(k string, v interface{}) {
-}
-
 // End does nothing.
 func (ms *MockSpan) End(options ...apitrace.SpanOption) {
 }

api/trace/tracetest/span.go

@@ -174,10 +174,6 @@ func (s *Span) SetAttributes(attrs ...label.KeyValue) {
 	}
 }
 
-func (s *Span) SetAttribute(k string, v interface{}) {
-	s.SetAttributes(label.Any(k, v))
-}
-
 // Name returns the name most recently set on the Span, either at or after creation time.
 // It cannot be change after End has been called on the Span.
 func (s *Span) Name() string {

bridge/opentracing/internal/mock.go

@@ -228,10 +228,6 @@ func (s *MockSpan) SetAttributes(attributes ...label.KeyValue) {
 	})
 }
 
-func (s *MockSpan) SetAttribute(k string, v interface{}) {
-	s.SetAttributes(label.Any(k, v))
-}
-
 func (s *MockSpan) applyUpdate(update otelbaggage.MapUpdate) {
 	s.Attributes = s.Attributes.Apply(update)
 }

sdk/trace/span.go

@@ -101,13 +101,6 @@ func (s *span) SetAttributes(attributes ...label.KeyValue) {
 	s.copyToCappedAttributes(attributes...)
 }
 
-func (s *span) SetAttribute(k string, v interface{}) {
-	attr := label.Any(k, v)
-	if attr.Value.Type() != label.INVALID {
-		s.SetAttributes(attr)
-	}
-}
-
 // End ends the span.
 //
 // The only SpanOption currently supported is WithTimestamp which will set the