From ce93decfc3717f9f919d51a2e1ff5b3f89b000ae Mon Sep 17 00:00:00 2001
From: Moritz Johner <beller.moritz@googlemail.com>
Date: Sat, 4 Jul 2020 17:02:05 +0200
Subject: [PATCH] fix null pointer in jaeger-spark-dependencies

fixes jaegertracing/jaeger-operator#1113

Signed-off-by: Moritz Johner <beller.moritz@googlemail.com>
---
 .../esmodeltranslator/modeltranslator.go      |  2 +-
 .../esmodeltranslator/modeltranslator_test.go | 27 +++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator.go b/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator.go
index 8cb46d181ca3..5978c50d215f 100644
--- a/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator.go
+++ b/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator.go
@@ -134,7 +134,7 @@ func toTime(nano pdata.TimestampUnixNano) time.Time {
 func references(links pdata.SpanLinkSlice, parentSpanID pdata.SpanID, traceID dbmodel.TraceID) ([]dbmodel.Reference, error) {
 	parentSpanIDSet := len(parentSpanID.Bytes()) != 0
 	if !parentSpanIDSet && links.Len() == 0 {
-		return nil, nil
+		return []dbmodel.Reference{}, nil
 	}
 
 	refsCount := links.Len()
diff --git a/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator_test.go b/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator_test.go
index 3b9c00271902..508ed0d585ec 100644
--- a/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator_test.go
+++ b/cmd/opentelemetry/app/exporter/elasticsearchexporter/esmodeltranslator/modeltranslator_test.go
@@ -159,6 +159,33 @@ func TestConvertSpan(t *testing.T) {
 	}, spans[0])
 }
 
+func TestSpanEmptyRef(t *testing.T) {
+	traces := traces("myservice")
+	span := addSpan(traces, "root", traceID, spanID)
+	span.SetStartTime(pdata.TimestampUnixNano(1000000))
+	span.SetEndTime(pdata.TimestampUnixNano(2000000))
+
+	c := &Translator{}
+	spans, err := c.ConvertSpans(traces)
+	require.NoError(t, err)
+	assert.Equal(t, 1, len(spans))
+	assert.Equal(t, &dbmodel.Span{
+		TraceID:         "30313233343536373839616263646566",
+		SpanID:          "3031323334353637",
+		StartTime:       1000,
+		Duration:        1000,
+		OperationName:   "root",
+		StartTimeMillis: 1,
+		Tags:            nil,
+		Logs:            nil,
+		References:      []dbmodel.Reference{}, // should not be nil
+		Process: dbmodel.Process{
+			ServiceName: "myservice",
+			Tags:        nil,
+		},
+	}, spans[0])
+}
+
 func TestEmpty(t *testing.T) {
 	c := &Translator{}
 	spans, err := c.ConvertSpans(pdata.NewTraces())