[newrelicexporter] Fix panic on missing span status (#775)

The span status is optional and a missing status means no error, updates
the newrelicexporter to handle this and adds tests to prevent
regression.

Resolves #348

exporter/newrelicexporter/transformer.go

@@ -91,7 +91,7 @@ func (t *transformer) SpanAttributes(span *tracepb.Span) map[string]interface{}
 
  length := 2
 
- isErr := t.isError(span.Status.Code)
+ isErr := span.Status != nil && span.Status.Code != 0
  if isErr {
  length++
  }
@@ -151,10 +151,6 @@ func (t *transformer) Timestamp(ts *timestamp.Timestamp) time.Time {
  return time.Unix(ts.Seconds, int64(ts.Nanos))
 }
 
-func (t *transformer) isError(code int32) bool {
- return code != 0
-}
-
 func (t *transformer) Metric(metric *metricspb.Metric) ([]telemetry.Metric, error) {
  if metric == nil || metric.MetricDescriptor == nil {
  return nil, errors.New("empty metric")

exporter/newrelicexporter/transformer_test.go

@@ -41,6 +41,21 @@ func TestTransformSpan(t *testing.T) {
  in *tracepb.Span
  want telemetry.Span
  }{
+ {
+ in: &tracepb.Span{
+ // No status means no error.
+ },
+ want: telemetry.Span{
+ ID: "0000000000000000",
+ TraceID: "00000000000000000000000000000000",
+ ServiceName: "test-service",
+ Attributes: map[string]interface{}{
+ "collector.name": name,
+ "collector.version": version,
+ "resource": "R1",
+ },
+ },
+ },
  {
  in: &tracepb.Span{
  Status: &tracepb.Status{},