enhance: Add `ParseCTraceContext` util function for tracing (#30883)

See also #29803

Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>

internal/querynodev2/segments/load_index_info.go

@@ -29,7 +29,6 @@ import (
 	"unsafe"
 
 	"github.com/pingcap/log"
-	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
@@ -209,16 +208,7 @@ func (li *LoadIndexInfo) appendIndexData(ctx context.Context, indexKeys []string
 		if paramtable.Get().CommonCfg.EnableStorageV2.GetAsBool() {
 			status = C.AppendIndexV3(li.cLoadIndexInfo)
 		} else {
-			span := trace.SpanFromContext(ctx)
-
-			traceID := span.SpanContext().TraceID()
-			spanID := span.SpanContext().SpanID()
-			traceCtx := C.CTraceContext{
-				traceID:    (*C.uint8_t)(unsafe.Pointer(&traceID[0])),
-				spanID:     (*C.uint8_t)(unsafe.Pointer(&spanID[0])),
-				traceFlags: (C.uint8_t)(span.SpanContext().TraceFlags()),
-			}
-
+			traceCtx := ParseCTraceContext(ctx)
 			status = C.AppendIndexV2(traceCtx, li.cLoadIndexInfo)
 		}
 		return nil, nil

internal/querynodev2/segments/segment.go

@@ -38,7 +38,6 @@ import (
 	"github.com/cockroachdb/errors"
 	"github.com/golang/protobuf/proto"
 	"go.opentelemetry.io/otel"
-	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/atomic"
 	"go.uber.org/zap"
 
@@ -471,15 +470,7 @@ func (s *LocalSegment) Search(ctx context.Context, searchReq *SearchRequest) (*S
 		return nil, merr.WrapErrSegmentNotLoaded(s.segmentID, "segment released")
 	}
 
-	span := trace.SpanFromContext(ctx)
-
-	traceID := span.SpanContext().TraceID()
-	spanID := span.SpanContext().SpanID()
-	traceCtx := C.CTraceContext{
-		traceID:    (*C.uint8_t)(unsafe.Pointer(&traceID[0])),
-		spanID:     (*C.uint8_t)(unsafe.Pointer(&spanID[0])),
-		traceFlags: (C.uint8_t)(span.SpanContext().TraceFlags()),
-	}
+	traceCtx := ParseCTraceContext(ctx)
 
 	hasIndex := s.ExistIndex(searchReq.searchFieldID)
 	log = log.With(zap.Bool("withIndex", hasIndex))
@@ -525,15 +516,7 @@ func (s *LocalSegment) Retrieve(ctx context.Context, plan *RetrievePlan) (*segco
 		zap.String("segmentType", s.typ.String()),
 	)
 
-	span := trace.SpanFromContext(ctx)
-
-	traceID := span.SpanContext().TraceID()
-	spanID := span.SpanContext().SpanID()
-	traceCtx := C.CTraceContext{
-		traceID:    (*C.uint8_t)(unsafe.Pointer(&traceID[0])),
-		spanID:     (*C.uint8_t)(unsafe.Pointer(&spanID[0])),
-		traceFlags: (C.uint8_t)(span.SpanContext().TraceFlags()),
-	}
+	traceCtx := ParseCTraceContext(ctx)
 
 	maxLimitSize := paramtable.Get().QuotaConfig.MaxOutputSize.GetAsInt64()
 	var retrieveResult RetrieveResult

internal/querynodev2/segments/trace.go

@@ -0,0 +1,44 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package segments
+
+/*
+#cgo pkg-config: milvus_segcore
+
+#include "segcore/segment_c.h"
+*/
+import "C"
+
+import (
+	"context"
+	"unsafe"
+
+	"go.opentelemetry.io/otel/trace"
+)
+
+// ParseCTraceContext parses tracing span and convert it into `C.CTraceContext`.
+func ParseCTraceContext(ctx context.Context) C.CTraceContext {
+	span := trace.SpanFromContext(ctx)
+
+	traceID := span.SpanContext().TraceID()
+	spanID := span.SpanContext().SpanID()
+	return C.CTraceContext{
+		traceID:    (*C.uint8_t)(unsafe.Pointer(&traceID[0])),
+		spanID:     (*C.uint8_t)(unsafe.Pointer(&spanID[0])),
+		traceFlags: (C.uint8_t)(span.SpanContext().TraceFlags()),
+	}
+}