feat: Update span interface to add a new function which will return span id (#245)

* get spanId

* added tests and impl

* Better Tests and impl for mock span

* Comments

---------

Co-authored-by: Raghav Rathi <[email protected]>

Author: stellarhuman

instrumentation/opentelemetry/span.go

@@ -112,6 +112,10 @@ func (s *Span) AddEvent(name string, ts time.Time, attributes map[string]interfa
 	s.Span.AddEvent(name, trace.WithTimestamp(ts), trace.WithAttributes(otAttributes...))
 }
 
+func (s *Span) GetSpanId() string {
+	return s.Span.SpanContext().SpanID().String()
+}
+
 func SpanFromContext(ctx context.Context) sdk.Span {
 	return &Span{trace.SpanFromContext(ctx)}
 }

instrumentation/opentelemetry/span_test.go

@@ -148,3 +148,9 @@ func TestLen(t *testing.T) {
 	// service.instance.id is added implicitly in StartSpan so 3 attributes will be present.
 	assert.Equal(t, 3, s.GetAttributes().Len())
 }
+
+func TestGetSpanID(t *testing.T) {
+	_, s, _ := StartSpan(context.Background(), "test_span", &sdk.SpanOptions{})
+	spanId := s.GetSpanId()
+	assert.NotEqual(t, 0, len(spanId))
+}

sdk/internal/mock/span.go

@@ -113,6 +113,11 @@ func (s *Span) AddEvent(name string, ts time.Time, attributes map[string]interfa
 	s.spanEvents = append(s.spanEvents, spanEvent{name, ts, attributes})
 }
 
+// This function has no use, it has been added just so that the interface in sdk/span.go remains implemented
+func (s *Span) GetSpanId() string {
+	return ""
+}
+
 type spanKey string
 
 func SpanFromContext(ctx context.Context) sdk.Span {

sdk/span.go

@@ -36,6 +36,9 @@ type Span interface {
 
 	// AddEvent adds an event to the Span with the provided name, timestamp and attributes.
 	AddEvent(name string, ts time.Time, attributes map[string]interface{})
+
+	//GetSpanId fetches the ID of the span that it is called upon
+	GetSpanId() string
 }
 
 // SpanFromContext retrieves the existing span from a context