[jaeger][v2] implement span links adjuster to operate on otlp data model

cmd/query/app/querysvc/adjuster/spanlinks.go

@@ -0,0 +1,50 @@
+// Copyright (c) 2024 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package adjuster
+
+import (
+	"go.opentelemetry.io/collector/pdata/ptrace"
+)
+
+// SpanLinks creates an adjuster that removes span links with empty trace IDs.
+func SpanLinks() Adjuster {
+	return Func(func(traces ptrace.Traces) (ptrace.Traces, error) {
+		adjuster := linksAdjuster{}
+		resourceSpans := traces.ResourceSpans()
+		for i := 0; i < resourceSpans.Len(); i++ {
+			rs := resourceSpans.At(i)
+			scopeSpans := rs.ScopeSpans()
+			for j := 0; j < scopeSpans.Len(); j++ {
+				ss := scopeSpans.At(j)
+				spans := ss.Spans()
+				for k := 0; k < spans.Len(); k++ {
+					span := spans.At(k)
+					adjuster.adjust(span)
+				}
+			}
+		}
+		return traces, nil
+	})
+}
+
+type linksAdjuster struct{}
+
+// adjust removes invalid links from a span.
+func (l linksAdjuster) adjust(span ptrace.Span) {
+	links := span.Links()
+	validLinks := ptrace.NewSpanLinkSlice()
+	for i := 0; i < links.Len(); i++ {
+		link := links.At(i)
+		if l.valid(link) {
+			newLink := validLinks.AppendEmpty()
+			link.CopyTo(newLink)
+		}
+	}
+	validLinks.CopyTo(span.Links())
+}
+
+// valid checks if a span link's TraceID is not empty.
+func (linksAdjuster) valid(link ptrace.SpanLink) bool {
+	return !link.TraceID().IsEmpty()
+}

cmd/query/app/querysvc/adjuster/spanlinks_test.go

@@ -0,0 +1,39 @@
+// Copyright (c) 2024 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package adjuster
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/pdata/pcommon"
+	"go.opentelemetry.io/collector/pdata/ptrace"
+)
+
+func TestLinksAdjuster(t *testing.T) {
+	trace := ptrace.NewTraces()
+	resourceSpans := trace.ResourceSpans().AppendEmpty()
+	scopeSpans := resourceSpans.ScopeSpans().AppendEmpty()
+
+	// span with no links
+	scopeSpans.Spans().AppendEmpty()
+
+	// span with empty traceID link
+	spanA := scopeSpans.Spans().AppendEmpty()
+	spanA.Links().AppendEmpty().SetTraceID(pcommon.NewTraceIDEmpty())
+
+	// span with 2 non-empty traceID links and 1 empty (or zero) traceID link
+	spanB := scopeSpans.Spans().AppendEmpty()
+	spanB.Links().AppendEmpty().SetTraceID(pcommon.TraceID([]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}))
+	spanB.Links().AppendEmpty().SetTraceID(pcommon.TraceID([]byte{0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0}))
+	spanB.Links().AppendEmpty().SetTraceID(pcommon.TraceID([]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}))
+
+	trace, err := SpanLinks().Adjust(trace)
+	spans := trace.ResourceSpans().At(0).ScopeSpans().At(0).Spans()
+	require.NoError(t, err)
+	assert.Equal(t, 0, spans.At(0).Links().Len())
+	assert.Equal(t, 0, spans.At(1).Links().Len())
+	assert.Equal(t, 2, spans.At(2).Links().Len())
+}