From ab82d08887286c0515fdfae187416ff94669822b Mon Sep 17 00:00:00 2001
From: Nathan <nabowler@users.noreply.github.com>
Date: Wed, 6 Oct 2021 13:28:53 -0400
Subject: [PATCH]  [zipkin] Encode span IDs as full 16-hex strings #601

Based on the openzipkin/b3-propagation specification, the SpanID and
ParentSpanID are to be encoded as 16 lower-hex characters.

https://github.com/jaegertracing/jaeger-client-go/pull/533 fixed this
for TraceID, and fixed the SpanID.String() method, but did not update
the Zipkin Propagator SpanID encoding.

This fix uses SpanID.String() to ensure proper encoding of the SpanID and
ParentSpandID within the Zipkin Propagator.

Signed-off-by: Nathan Bowler <nzb301@psu.edu>
---
 zipkin/propagation.go      |  4 ++--
 zipkin/propagation_test.go | 20 ++++++++++----------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/zipkin/propagation.go b/zipkin/propagation.go
index 722b0875..cd7d52d7 100644
--- a/zipkin/propagation.go
+++ b/zipkin/propagation.go
@@ -61,9 +61,9 @@ func (p Propagator) Inject(
 
 	textMapWriter.Set("x-b3-traceid", sc.TraceID().String())
 	if sc.ParentID() != 0 {
-		textMapWriter.Set("x-b3-parentspanid", strconv.FormatUint(uint64(sc.ParentID()), 16))
+		textMapWriter.Set("x-b3-parentspanid", sc.ParentID().String())
 	}
-	textMapWriter.Set("x-b3-spanid", strconv.FormatUint(uint64(sc.SpanID()), 16))
+	textMapWriter.Set("x-b3-spanid", sc.SpanID().String())
 	if sc.IsSampled() {
 		textMapWriter.Set("x-b3-sampled", "1")
 	} else {
diff --git a/zipkin/propagation_test.go b/zipkin/propagation_test.go
index d7c5c6f6..95771a7e 100644
--- a/zipkin/propagation_test.go
+++ b/zipkin/propagation_test.go
@@ -33,31 +33,31 @@ var (
 var (
 	rootSampledHeader = opentracing.TextMapCarrier{
 		"x-b3-traceid": "0000000000000001",
-		"x-b3-spanid":  "2",
+		"x-b3-spanid":  "0000000000000002",
 		"x-b3-sampled": "1",
 		"baggage-foo":  "bar",
 	}
 	nonRootSampledHeader = opentracing.TextMapCarrier{
 		"x-b3-traceid":      "0000000000000001",
-		"x-b3-spanid":       "2",
-		"x-b3-parentspanid": "1",
+		"x-b3-spanid":       "0000000000000002",
+		"x-b3-parentspanid": "0000000000000001",
 		"x-b3-sampled":      "1",
 	}
 	nonRootNonSampledHeader = opentracing.TextMapCarrier{
 		"x-b3-traceid":      "0000000000000001",
-		"x-b3-spanid":       "2",
-		"x-b3-parentspanid": "1",
+		"x-b3-spanid":       "0000000000000002",
+		"x-b3-parentspanid": "0000000000000001",
 		"x-b3-sampled":      "0",
 	}
 	rootSampledBooleanHeader = opentracing.TextMapCarrier{
 		"x-b3-traceid": "0000000000000001",
-		"x-b3-spanid":  "2",
+		"x-b3-spanid":  "0000000000000002",
 		"x-b3-sampled": "true",
 		"baggage-foo":  "bar",
 	}
 	nonRootSampledBooleanHeader = opentracing.TextMapCarrier{
 		"x-b3-traceid":      "0000000000000001",
-		"x-b3-spanid":       "2",
+		"x-b3-spanid":       "0000000000000002",
 		"x-b3-parentspanid": "1",
 		"x-b3-sampled":      "true",
 	}
@@ -69,12 +69,12 @@ var (
 	}
 	sampled128bitTraceID = opentracing.TextMapCarrier{
 		"x-b3-traceid": "463ac35c9f6413ad48485a3953bb6124",
-		"x-b3-spanid":  "2",
+		"x-b3-spanid":  "0000000000000002",
 		"x-b3-sampled": "1",
 	}
 	invalidTraceID = opentracing.TextMapCarrier{
 		"x-b3-traceid": "00000000000000000000000000000000",
-		"x-b3-spanid":  "2",
+		"x-b3-spanid":  "0000000000000002",
 		"x-b3-sampled": "1",
 	}
 )
@@ -157,7 +157,7 @@ func TestCustomBaggagePrefix(t *testing.T) {
 	assert.Nil(t, err)
 	m := opentracing.TextMapCarrier{
 		"x-b3-traceid": "0000000000000001",
-		"x-b3-spanid":  "2",
+		"x-b3-spanid":  "0000000000000002",
 		"x-b3-sampled": "1",
 		"emoji:)foo":   "bar",
 	}