Updated opencensus-go

Signed-off-by: Francesco Guardiani <francescoguard@gmail.com>

go.mod

@@ -28,7 +28,7 @@ require (
 	github.com/stretchr/testify v1.5.1
 	github.com/xanzy/go-gitlab v0.28.0
 	gitlab.com/flimzy/testy v0.2.1 // indirect
-	go.opencensus.io v0.22.4
+	go.opencensus.io v0.22.5-0.20200716030834-3456e1d174b2
 	go.opentelemetry.io/otel v0.4.2 // indirect
 	go.uber.org/zap v1.14.1
 	golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e

go.sum

@@ -971,6 +971,8 @@ go.opencensus.io v0.22.3 h1:8sGtKOrtQqkN1bp2AtX+misvLIlOmsEsNd+9NIcPEm8=
 go.opencensus.io v0.22.3/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opencensus.io v0.22.4 h1:LYy1Hy3MJdrCdMwwzxA/dRok4ejH+RwNGbuoD9fCjto=
 go.opencensus.io v0.22.4/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
+go.opencensus.io v0.22.5-0.20200716030834-3456e1d174b2 h1:p7zhKkxd+cS4tMYPy/HkKVczBa28t8TU+sUh7GJ/Ge4=
+go.opencensus.io v0.22.5-0.20200716030834-3456e1d174b2/go.mod h1:yxeiOL68Rb0Xd1ddK5vPZ/oVn4vY4Ynel7k9FzqtOIw=
 go.opentelemetry.io/otel v0.2.3/go.mod h1:OgNpQOjrlt33Ew6Ds0mGjmcTQg/rhUctsbkRdk/g1fw=
 go.opentelemetry.io/otel v0.4.2 h1:nT+GOqqRR1cIY92xmo1DeiXLHtIlXH1KLRgnsnhuNrs=
 go.opentelemetry.io/otel v0.4.2/go.mod h1:OgNpQOjrlt33Ew6Ds0mGjmcTQg/rhUctsbkRdk/g1fw=

kafka/channel/pkg/dispatcher/tracing.go

@@ -17,146 +17,48 @@ limitations under the License.
 package dispatcher
 
 import (
-	"encoding/hex"
-	"fmt"
-	"regexp"
-	"strings"
-
 	"github.com/Shopify/sarama"
+	"go.opencensus.io/plugin/ochttp/propagation/tracecontext"
 	"go.opencensus.io/trace"
-	"go.opencensus.io/trace/tracestate"
 )
 
 const (
-	supportedVersion  = 0
 	traceParentHeader = "traceparent"
 	traceStateHeader  = "tracestate"
-	maxVersion        = 254
-	maxTracestateLen  = 512
-	trimOWSRegexFmt   = `^[\x09\x20]*(.*[^\x20\x09])[\x09\x20]*$`
 )
 
-var trimOWSRegExp = regexp.MustCompile(trimOWSRegexFmt)
-
-// Part of this code is took from https://github.com/census-instrumentation/opencensus-go/blob/master/plugin/ochttp/propagation/tracecontext/propagation.go
-// Apache License 2.0
-// TODO(slinkydeveloper) remove this code as soon as https://github.com/census-instrumentation/opencensus-go/pull/1218 is merged
+var format = &tracecontext.HTTPFormat{}
 
 func serializeTrace(spanContext trace.SpanContext) []sarama.RecordHeader {
-	var headers []sarama.RecordHeader
-
-	traceparent := fmt.Sprintf("%x-%x-%x-%x",
-		[]byte{supportedVersion},
-		spanContext.TraceID[:],
-		spanContext.SpanID[:],
-		[]byte{byte(spanContext.TraceOptions)},
-	)
-	headers = append(headers, sarama.RecordHeader{Key: []byte(traceParentHeader), Value: []byte(traceparent)})
-
-	if len(spanContext.Tracestate.Entries()) != 0 {
-		entries := make([]string, 0, len(spanContext.Tracestate.Entries()))
-		for _, entry := range spanContext.Tracestate.Entries() {
-			entries = append(entries, strings.Join([]string{entry.Key, entry.Value}, "="))
-		}
-		tracestate := strings.Join(entries, ",")
-
-		headers = append(headers, sarama.RecordHeader{Key: []byte(traceStateHeader), Value: []byte(tracestate)})
-	}
-
-	return headers
+	tp, ts := format.SpanContextToHeaders(spanContext)
+
+	if ts != "" {
+		return []sarama.RecordHeader{{
+			Key:   []byte(traceParentHeader),
+			Value: []byte(tp),
+		}, {
+			Key:   []byte(traceStateHeader),
+			Value: []byte(ts),
+		}}
+	}
+
+	return []sarama.RecordHeader{{
+		Key:   []byte(traceParentHeader),
+		Value: []byte(tp),
+	}}
 }
 
 func parseSpanContext(headers map[string][]byte) (sc trace.SpanContext, ok bool) {
-	hBytes, ok := headers[traceParentHeader]
+	tpBytes, ok := headers[traceParentHeader]
 	if !ok {
 		return trace.SpanContext{}, false
 	}
-	h := string(hBytes)
-
-	sections := strings.Split(h, "-")
-	if len(sections) < 4 {
-		return trace.SpanContext{}, false
-	}
-
-	if len(sections[0]) != 2 {
-		return trace.SpanContext{}, false
-	}
-	ver, err := hex.DecodeString(sections[0])
-	if err != nil {
-		return trace.SpanContext{}, false
-	}
-	version := int(ver[0])
-	if version > maxVersion {
-		return trace.SpanContext{}, false
-	}
-
-	if version == 0 && len(sections) != 4 {
-		return trace.SpanContext{}, false
-	}
-
-	if len(sections[1]) != 32 {
-		return trace.SpanContext{}, false
-	}
-	tid, err := hex.DecodeString(sections[1])
-	if err != nil {
-		return trace.SpanContext{}, false
-	}
-	copy(sc.TraceID[:], tid)
+	tp := string(tpBytes)
 
-	if len(sections[2]) != 16 {
-		return trace.SpanContext{}, false
-	}
-	sid, err := hex.DecodeString(sections[2])
-	if err != nil {
-		return trace.SpanContext{}, false
-	}
-	copy(sc.SpanID[:], sid)
-
-	opts, err := hex.DecodeString(sections[3])
-	if err != nil || len(opts) < 1 {
-		return trace.SpanContext{}, false
-	}
-	sc.TraceOptions = trace.TraceOptions(opts[0])
-
-	// Don't allow all zero trace or span ID.
-	if sc.TraceID == [16]byte{} || sc.SpanID == [8]byte{} {
-		return trace.SpanContext{}, false
-	}
-
-	sc.Tracestate = tracestateFromRequest(headers)
-	return sc, true
-}
-
-func tracestateFromRequest(headers map[string][]byte) *tracestate.Tracestate {
-	hBytes, ok := headers[traceStateHeader]
-	if !ok {
-		return nil
-	}
-	h := string(hBytes)
-
-	var entries []tracestate.Entry
-	pairs := strings.Split(h, ",")
-	hdrLenWithoutOWS := len(pairs) - 1 // Number of commas
-	for _, pair := range pairs {
-		matches := trimOWSRegExp.FindStringSubmatch(pair)
-		if matches == nil {
-			return nil
-		}
-		pair = matches[1]
-		hdrLenWithoutOWS += len(pair)
-		if hdrLenWithoutOWS > maxTracestateLen {
-			return nil
-		}
-		kv := strings.Split(pair, "=")
-		if len(kv) != 2 {
-			return nil
-		}
-		entries = append(entries, tracestate.Entry{Key: kv[0], Value: kv[1]})
-	}
-	ts, err := tracestate.New(nil, entries...)
-	if err != nil {
-		return nil
+	ts := ""
+	if tsBytes, ok := headers[traceStateHeader]; ok {
+		ts = string(tsBytes)
 	}
 
-	return ts
+	return format.SpanContextFromHeaders(tp, ts)
 }