[VOL-3196] Enhanced gRPC interfaces to create and propagate Span for log correlation
Change-Id: Id9f8e549aaa192f83b8ac66d4252f71da6d11449
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing/id_extract.go b/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing/id_extract.go
new file mode 100644
index 0000000..d19f3c8
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing/id_extract.go
@@ -0,0 +1,67 @@
+package grpc_opentracing
+
+import (
+ "strings"
+
+ grpc_ctxtags "github.com/grpc-ecosystem/go-grpc-middleware/tags"
+ opentracing "github.com/opentracing/opentracing-go"
+ "google.golang.org/grpc/grpclog"
+)
+
+const (
+ TagTraceId = "trace.traceid"
+ TagSpanId = "trace.spanid"
+ TagSampled = "trace.sampled"
+ jaegerNotSampledFlag = "0"
+)
+
+// injectOpentracingIdsToTags writes trace data to ctxtags.
+// This is done in an incredibly hacky way, because the public-facing interface of opentracing doesn't give access to
+// the TraceId and SpanId of the SpanContext. Only the Tracer's Inject/Extract methods know what these are.
+// Most tracers have them encoded as keys with 'traceid' and 'spanid':
+// https://github.com/openzipkin/zipkin-go-opentracing/blob/594640b9ef7e5c994e8d9499359d693c032d738c/propagation_ot.go#L29
+// https://github.com/opentracing/basictracer-go/blob/1b32af207119a14b1b231d451df3ed04a72efebf/propagation_ot.go#L26
+// Jaeger from Uber use one-key schema with next format '{trace-id}:{span-id}:{parent-span-id}:{flags}'
+// https://www.jaegertracing.io/docs/client-libraries/#trace-span-identity
+func injectOpentracingIdsToTags(span opentracing.Span, tags grpc_ctxtags.Tags) {
+ if err := span.Tracer().Inject(span.Context(), opentracing.HTTPHeaders, &tagsCarrier{tags}); err != nil {
+ grpclog.Infof("grpc_opentracing: failed extracting trace info into ctx %v", err)
+ }
+}
+
+// tagsCarrier is a really hacky way of
+type tagsCarrier struct {
+ grpc_ctxtags.Tags
+}
+
+func (t *tagsCarrier) Set(key, val string) {
+ key = strings.ToLower(key)
+ if strings.Contains(key, "traceid") {
+ t.Tags.Set(TagTraceId, val) // this will most likely be base-16 (hex) encoded
+ }
+
+ if strings.Contains(key, "spanid") && !strings.Contains(strings.ToLower(key), "parent") {
+ t.Tags.Set(TagSpanId, val) // this will most likely be base-16 (hex) encoded
+ }
+
+ if strings.Contains(key, "sampled") {
+ switch val {
+ case "true", "false":
+ t.Tags.Set(TagSampled, val)
+ }
+ }
+
+ if key == "uber-trace-id" {
+ parts := strings.Split(val, ":")
+ if len(parts) == 4 {
+ t.Tags.Set(TagTraceId, parts[0])
+ t.Tags.Set(TagSpanId, parts[1])
+
+ if parts[3] != jaegerNotSampledFlag {
+ t.Tags.Set(TagSampled, "true")
+ } else {
+ t.Tags.Set(TagSampled, "false")
+ }
+ }
+ }
+}