1 files changed, 50 insertions, 0 deletions
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 000000000..196240fd6
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing/id_extract.go
@@ -0,0 +1,50 @@
+// Copyright 2017 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_opentracing
+
+import (
+	"strings"
+
+	"github.com/grpc-ecosystem/go-grpc-middleware/tags"
+	"github.com/opentracing/opentracing-go"
+	"google.golang.org/grpc/grpclog"
+)
+
+const (
+	TagTraceId = "trace.traceid"
+	TagSpanId  = "trace.spanid"
+)
+
+// hackyInjectOpentracingIdsToTags writes the given context to the 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 hackyInjectOpentracingIdsToTags(span opentracing.Span, tags grpc_ctxtags.Tags) {
+	if err := span.Tracer().Inject(span.Context(), opentracing.HTTPHeaders, &hackyTagsCarrier{tags}); err != nil {
+		grpclog.Printf("grpc_opentracing: failed extracting trace info into ctx %v", err)
+	}
+}
+
+// hackyTagsCarrier is a really hacky way of
+type hackyTagsCarrier struct {
+	grpc_ctxtags.Tags
+}
+
+func (t *hackyTagsCarrier) Set(key, val string) {
+	if strings.Contains(key, "traceid") || strings.Contains(strings.ToLower(key), "traceid") {
+		t.Tags.Set(TagTraceId, val) // this will most likely be base-16 (hex) encoded
+	} else if (strings.Contains(key, "spanid") && !strings.Contains(key, "parent")) || (strings.Contains(strings.ToLower(key), "spanid") && !strings.Contains(strings.ToLower(key), "parent")) {
+		t.Tags.Set(TagSpanId, val) // this will most likely be base-16 (hex) encoded
+	} else if key == "uber-trace-id" {
+		parts := strings.Split(val, ":")
+		if len(parts) >= 2 {
+			t.Tags.Set(TagTraceId, parts[0])
+			t.Tags.Set(TagSpanId, parts[1])
+		}
+	}
+}