Added integration support for DataDog APM Tracing

vendor/gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentracer/span.go

@@ -0,0 +1,83 @@
+package opentracer
+
+import (
+	"fmt"
+
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
+
+	opentracing "github.com/opentracing/opentracing-go"
+	"github.com/opentracing/opentracing-go/log"
+)
+
+var _ opentracing.Span = (*span)(nil)
+
+// span implements opentracing.Span on top of ddtrace.Span.
+type span struct {
+	ddtrace.Span
+	*opentracer
+}
+
+func (s *span) Context() opentracing.SpanContext                      { return s.Span.Context() }
+func (s *span) Finish()                                               { s.Span.Finish() }
+func (s *span) Tracer() opentracing.Tracer                            { return s.opentracer }
+func (s *span) LogEvent(event string)                                 { /* deprecated */ }
+func (s *span) LogEventWithPayload(event string, payload interface{}) { /* deprecated */ }
+func (s *span) Log(data opentracing.LogData)                          { /* deprecated */ }
+
+func (s *span) FinishWithOptions(opts opentracing.FinishOptions) {
+	for _, lr := range opts.LogRecords {
+		if len(lr.Fields) > 0 {
+			s.LogFields(lr.Fields...)
+		}
+	}
+	s.Span.Finish(tracer.FinishTime(opts.FinishTime))
+}
+
+func (s *span) LogFields(fields ...log.Field) {
+	// catch standard opentracing keys and adjust to internal ones as per spec:
+	// https://github.com/opentracing/specification/blob/master/semantic_conventions.md#log-fields-table
+	for _, f := range fields {
+		switch f.Key() {
+		case "event":
+			if v, ok := f.Value().(string); ok && v == "error" {
+				s.SetTag("error", true)
+			}
+		case "error", "error.object":
+			if err, ok := f.Value().(error); ok {
+				s.SetTag("error", err)
+			}
+		case "message":
+			s.SetTag(ext.ErrorMsg, fmt.Sprint(f.Value()))
+		case "stack":
+			s.SetTag(ext.ErrorStack, fmt.Sprint(f.Value()))
+		default:
+			// not implemented
+		}
+	}
+}
+
+func (s *span) LogKV(keyVals ...interface{}) {
+	fields, err := log.InterleavedKVToFields(keyVals...)
+	if err != nil {
+		// TODO(gbbr): create a log package
+		return
+	}
+	s.LogFields(fields...)
+}
+
+func (s *span) SetBaggageItem(key, val string) opentracing.Span {
+	s.Span.SetBaggageItem(key, val)
+	return s
+}
+
+func (s *span) SetOperationName(operationName string) opentracing.Span {
+	s.Span.SetOperationName(operationName)
+	return s
+}
+
+func (s *span) SetTag(key string, value interface{}) opentracing.Span {
+	s.Span.SetTag(key, value)
+	return s
+}