move the OnEnding processor into internal/x

Author: dmathieu

CHANGELOG.md

@@ -10,7 +10,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ### Added
 
-- The `OnEndingSpanProcessor` in `go.opentelemetry.io/otel/sdk/trace` to implement the `OnEnding` callback. (#5756)
+- Support for the `OnEnding` callback in span processors. (#5756)
 
 ### Removed
 

sdk/internal/x/onending_processor.go

@@ -0,0 +1,12 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package x // import "go.opentelemetry.io/otel/sdk/internal/x"
+
+// OnEndingSpanProcessor represents span processors that allow mutating spans
+// just before they are ended and made immutable.
+type OnEndingSpanProcessor interface {
+	// OnEnding is called while the span is finished, and while spans are still
+	// mutable. It is called synchronously and cannot block.
+	OnEnding(ReadWriteSpan)
+}

sdk/trace/span.go

@@ -19,6 +19,7 @@ import (
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/internal/global"
 	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/sdk/internal/x"
 	"go.opentelemetry.io/otel/sdk/resource"
 	semconv "go.opentelemetry.io/otel/semconv/v1.26.0"
 	"go.opentelemetry.io/otel/trace"
@@ -427,7 +428,7 @@ func (s *recordingSpan) End(options ...trace.SpanEndOption) {
 
 	sps := s.tracer.provider.getSpanProcessors()
 	for _, sp := range sps {
-		if oesp, ok := sp.sp.(OnEndingSpanProcessor); ok {
+		if oesp, ok := sp.sp.(x.OnEndingSpanProcessor); ok {
 			oesp.OnEnding(s)
 		}
 	}

sdk/trace/span_processor.go

@@ -49,17 +49,6 @@ type SpanProcessor interface {
 	// must never be done outside of a new major release.
 }
 
-// OnEndingSpanProcessor represents span processors that allow mutating spans
-// just before they are ended and made immutable.
-//
-// NOT STABLE: This interface still has a status of "development", and may have
-// breaking changes.
-type OnEndingSpanProcessor interface {
-	// OnEnding is called while the span is finished, and while spans are still
-	// mutable. It is called synchronously and cannot block.
-	OnEnding(ReadWriteSpan)
-}
-
 type spanProcessorState struct {
 	sp    SpanProcessor
 	state sync.Once