update X-Canary Header specification, reference to https://www.w3.org…

…/TR/trace-context/#tracestate-header
teambition · May 29, 2020 · 33673c1 · 33673c1
1 parent e0d8282
commit 33673c1
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Showing 5 changed files with 166 additions and 41 deletions.
diff --git a/pkg/middlewares/canary/canary.go b/pkg/middlewares/canary/canary.go
@@ -50,7 +50,7 @@ func New(ctx context.Context, next http.Handler, cfg dynamic.Canary, name string
 	logger := log.FromContext(middlewares.GetLoggerCtx(ctx, name, typeName))
 
 	if cfg.Product == "" {
-		return nil, fmt.Errorf("product name required for Canary middleware")
+		return nil, fmt.Errorf("product name required for canary middleware")
 	}
 
 	expiration := time.Duration(cfg.CacheExpiration)
@@ -97,7 +97,13 @@ func (c *Canary) processRequestID(rw http.ResponseWriter, req *http.Request) {
 	requestID := req.Header.Get(headerXRequestID)
 	if c.addRequestID {
 		if requestID == "" {
-			requestID = generatorUUID()
+			// extract trace-id as x-request-id
+			// https://www.w3.org/TR/trace-context/#traceparent-header
+			if traceparent := req.Header.Get("traceparent"); len(traceparent) >= 55 {
+				requestID = traceparent[3:35]
+			} else {
+				requestID = generatorUUID()
+			}
 			req.Header.Set(headerXRequestID, requestID)
 		}
 		rw.Header().Set(headerXRequestID, requestID)
@@ -112,6 +118,9 @@ func (c *Canary) processRequestID(rw http.ResponseWriter, req *http.Request) {
 		logData.Core["XRequestID"] = requestID
 		logData.Core["UserAgent"] = req.Header.Get(headerUA)
 		logData.Core["Referer"] = req.Header.Get("Referer")
+		if traceparent := req.Header.Get("traceparent"); traceparent != "" {
+			logData.Core["Traceparent"] = traceparent
+		}
 	}
 }
 
@@ -136,10 +145,10 @@ func (c *Canary) processCanary(rw http.ResponseWriter, req *http.Request) {
 		if info.label == "" && info.uid != "" {
 			labels := c.ls.MustLoadLabels(req.Context(), info.uid, req.Header.Get(headerXRequestID))
 			for _, l := range labels {
-				if info.client != "" && !l.MatchClient(info.client) {
+				if !l.MatchClient(info.client) {
 					continue
 				}
-				if info.channel != "" && !l.MatchChannel(info.channel) {
+				if !l.MatchChannel(info.channel) {
 					continue
 				}
 				info.label = l.Label
@@ -154,7 +163,7 @@ func (c *Canary) processCanary(rw http.ResponseWriter, req *http.Request) {
 
 	if logData := accesslog.GetLogData(req); logData != nil {
 		logData.Core["UID"] = info.uid
-		logData.Core["XCanary"] = req.Header.Values(headerXCanary)
+		logData.Core["XCanary"] = info.String()
 	}
 }
 
@@ -239,6 +248,12 @@ func extractUserIDFromBase64(s string) string {
 	return ""
 }
 
+// Canary Header specification, reference to https://www.w3.org/TR/trace-context/#tracestate-header
+// X-Canary: label=beta,nofallback
+// X-Canary: client=iOS,channel=stable,app=teambition,version=v10.0
+// full example
+// X-Canary: label=beta,product=urbs,uid=5c4057f0be825b390667abee,client=iOS,channel=stable,app=teambition,version=v10.0,nofallback,testing
+// support fields: label, product, uid, client, channel, app, version, nofallback, testing
 type canaryHeader struct {
 	label      string
 	product    string
@@ -252,8 +267,32 @@ type canaryHeader struct {
 }
 
 // uid and product will not be extracted
+// standard
+// X-Canary: label=beta,product=urbs,uid=5c4057f0be825b390667abee,nofallback ...
+// and compatible with
+// X-Canary: beta
+// or
+// X-Canary: label=beta; product=urbs; uid=5c4057f0be825b390667abee; nofallback ...
+// or
+// X-Canary: label=beta
+// X-Canary: product=urbs
+// X-Canary: uid=5c4057f0be825b390667abee
+// X-Canary: nofallback
 func (ch *canaryHeader) fromHeader(header http.Header, trust bool) {
-	ch.feed(header.Values(headerXCanary), trust)
+	vals := header.Values(headerXCanary)
+	if len(vals) == 1 {
+		if strings.IndexByte(vals[0], ',') > 0 {
+			vals = strings.Split(vals[0], ",")
+		} else if strings.IndexByte(vals[0], ';') > 0 {
+			vals = strings.Split(vals[0], ";")
+		}
+	}
+	ch.feed(vals, trust)
+}
+
+// label should not be empty
+func (ch *canaryHeader) intoHeader(header http.Header) {
+	header.Set(headerXCanary, ch.String())
 }
 
 func (ch *canaryHeader) feed(vals []string, trust bool) {
@@ -287,33 +326,35 @@ func (ch *canaryHeader) feed(vals []string, trust bool) {
 }
 
 // label should not be empty
-func (ch *canaryHeader) intoHeader(header http.Header) {
+func (ch *canaryHeader) String() string {
 	if ch.label == "" {
-		return
+		return ""
 	}
-	header.Set(headerXCanary, fmt.Sprintf("label=%s", ch.label))
+	vals := make([]string, 0, 4)
+	vals = append(vals, fmt.Sprintf("label=%s", ch.label))
 	if ch.product != "" {
-		header.Add(headerXCanary, fmt.Sprintf("product=%s", ch.product))
+		vals = append(vals, fmt.Sprintf("product=%s", ch.product))
 	}
 	if ch.uid != "" {
-		header.Add(headerXCanary, fmt.Sprintf("uid=%s", ch.uid))
+		vals = append(vals, fmt.Sprintf("uid=%s", ch.uid))
 	}
 	if ch.client != "" {
-		header.Add(headerXCanary, fmt.Sprintf("client=%s", ch.client))
+		vals = append(vals, fmt.Sprintf("client=%s", ch.client))
 	}
 	if ch.channel != "" {
-		header.Add(headerXCanary, fmt.Sprintf("channel=%s", ch.channel))
+		vals = append(vals, fmt.Sprintf("channel=%s", ch.channel))
 	}
 	if ch.app != "" {
-		header.Add(headerXCanary, fmt.Sprintf("app=%s", ch.app))
+		vals = append(vals, fmt.Sprintf("app=%s", ch.app))
 	}
 	if ch.version != "" {
-		header.Add(headerXCanary, fmt.Sprintf("version=%s", ch.version))
+		vals = append(vals, fmt.Sprintf("version=%s", ch.version))
 	}
 	if ch.nofallback {
-		header.Add(headerXCanary, "nofallback")
+		vals = append(vals, "nofallback")
 	}
 	if ch.testing {
-		header.Add(headerXCanary, "testing")
+		vals = append(vals, "testing")
 	}
+	return strings.Join(vals, ",")
 }
diff --git a/pkg/middlewares/canary/canary_test.go b/pkg/middlewares/canary/canary_test.go
@@ -66,6 +66,20 @@ func TestCanaryHeader(t *testing.T) {
 		a.Equal("version", ch.version)
 		a.True(ch.nofallback)
 		a.True(ch.testing)
+
+		ch = &canaryHeader{}
+		h = http.Header{}
+		h.Set(headerXCanary, "label=label,version=version,app=app, channel=channel,client=client, uid=uid,product=product,ip=ip,nofallback,testing")
+		ch.fromHeader(h, false)
+		a.Equal("label", ch.label)
+		a.Equal("", ch.product)
+		a.Equal("", ch.uid)
+		a.Equal("client", ch.client)
+		a.Equal("channel", ch.channel)
+		a.Equal("app", ch.app)
+		a.Equal("version", ch.version)
+		a.True(ch.nofallback)
+		a.True(ch.testing)
 	})
 
 	t.Run("intoHeader should work", func(t *testing.T) {
@@ -74,7 +88,7 @@ func TestCanaryHeader(t *testing.T) {
 		ch := &canaryHeader{}
 		h := http.Header{}
 		ch.intoHeader(h)
-		a.Equal(0, len(h.Values(headerXCanary)))
+		a.Equal("", h.Get(headerXCanary))
 
 		ch = &canaryHeader{
 			label:   "label",
@@ -84,7 +98,7 @@ func TestCanaryHeader(t *testing.T) {
 		}
 		h = http.Header{}
 		ch.intoHeader(h)
-		a.Equal(4, len(h.Values(headerXCanary)))
+		a.Equal("label=label,product=product,uid=uid,channel=channel", h.Get(headerXCanary))
 
 		chn := &canaryHeader{}
 		chn.fromHeader(h, true)
@@ -103,7 +117,7 @@ func TestCanaryHeader(t *testing.T) {
 		}
 		h = http.Header{}
 		ch.intoHeader(h)
-		a.Equal(9, len(h.Values(headerXCanary)))
+		a.Equal("label=label,product=product,uid=uid,client=client,channel=channel,app=app,version=version,nofallback,testing", h.Get(headerXCanary))
 
 		chn = &canaryHeader{}
 		chn.fromHeader(h, true)
@@ -256,8 +270,7 @@ func TestCanary(t *testing.T) {
 
 		req = httptest.NewRequest("GET", "http://example.com/foo", nil)
 		rw = httptest.NewRecorder()
-		req.Header.Set(headerXCanary, "label=beta")
-		req.Header.Add(headerXCanary, "client=iOS")
+		req.Header.Set(headerXCanary, "label=beta,client=iOS")
 		req.AddCookie(&http.Cookie{Name: headerXCanary, Value: "stable"})
 		c.processCanary(rw, req)
 		ch = &canaryHeader{}

diff --git a/pkg/middlewares/canary/request.go b/pkg/middlewares/canary/request.go
@@ -15,6 +15,7 @@ import (
 
 	"github.com/containous/traefik/v2/pkg/log"
 	"github.com/containous/traefik/v2/pkg/version"
+	"github.com/opentracing/opentracing-go"
 )
 
 func init() {
@@ -93,6 +94,13 @@ func getUserLabels(ctx context.Context, api, xRequestID string) (*labelsRes, err
 
 	req.Header.Set(headerUA, userAgent)
 	req.Header.Set(headerXRequestID, xRequestID)
+	if span := opentracing.SpanFromContext(ctx); span != nil {
+		opentracing.GlobalTracer().Inject(
+			span.Context(),
+			opentracing.HTTPHeaders,
+			opentracing.HTTPHeadersCarrier(req.Header))
+	}
+
 	resp, err := client.Do(req)
 	if err != nil {
 		if err.(*url.Error).Unwrap() == context.Canceled {

diff --git a/pkg/server/service/loadbalancer/lrr/lrr.go b/pkg/server/service/loadbalancer/lrr/lrr.go
@@ -8,10 +8,6 @@ import (
 	"strings"
 )
 
-const labelKey = "X-Canary"
-
-var isPortReg = regexp.MustCompile(`^\d+$`)
-
 type namedHandler struct {
 	http.Handler
 	name string
@@ -51,21 +47,7 @@ type Balancer struct {
 }
 
 func (b *Balancer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
-	// X-Canary: beta
-	// X-Canary: label=beta; product=urbs; uid=5c4057f0be825b390667abee; nofallback ...
-	label := ""
-	fallback := true
-	for i, v := range req.Header.Values(labelKey) {
-		switch {
-		case strings.HasPrefix(v, "label="):
-			label = v[6:]
-		case v == "nofallback":
-			fallback = false
-		case i == 0:
-			label = v
-		}
-	}
-
+	label, fallback := extractLabel(req.Header)
 	name := b.serviceName
 	if label != "" {
 		name = fmt.Sprintf("%s-%s", name, label)
@@ -90,6 +72,8 @@ func (b *Balancer) AddService(fullServiceName string, handler http.Handler) {
 	b.handlers = b.handlers.AppendAndSort(h)
 }
 
+var isPortReg = regexp.MustCompile(`^\d+$`)
+
 // full service name format (build by fullServiceName function): namespace-serviceName-port
 func removeNsPort(fullServiceName, ServiceName string) string {
 	i := strings.Index(fullServiceName, ServiceName)
@@ -98,3 +82,33 @@ func removeNsPort(fullServiceName, ServiceName string) string {
 	}
 	return strings.TrimRight(fullServiceName, "0123456789-") // remove port
 }
+
+func extractLabel(header http.Header) (string, bool) {
+	// standard specification, reference to https://www.w3.org/TR/trace-context/#tracestate-header
+	// X-Canary: label=beta,product=urbs,uid=5c4057f0be825b390667abee,nofallback ...
+	// and compatible with
+	// X-Canary: beta
+	// X-Canary: label=beta; product=urbs; uid=5c4057f0be825b390667abee; nofallback ...
+	label := ""
+	fallback := true
+	vals := header.Values("X-Canary")
+	if len(vals) == 1 {
+		if strings.IndexByte(vals[0], ',') > 0 {
+			vals = strings.Split(vals[0], ",")
+		} else if strings.IndexByte(vals[0], ';') > 0 {
+			vals = strings.Split(vals[0], ";")
+		}
+	}
+	for i, v := range vals {
+		v = strings.TrimSpace(v)
+		switch {
+		case strings.HasPrefix(v, "label="):
+			label = v[6:]
+		case v == "nofallback":
+			fallback = false
+		case i == 0:
+			label = v
+		}
+	}
+	return label, fallback
+}
diff --git a/pkg/server/service/loadbalancer/lrr/lrr_test.go b/pkg/server/service/loadbalancer/lrr/lrr_test.go
@@ -95,4 +95,53 @@ func TestLRRBalancer(t *testing.T) {
 		h = s.Match("lr", true)
 		a.Nil(h)
 	})
+
+	t.Run("extractLabel should work", func(t *testing.T) {
+		a := assert.New(t)
+		header := http.Header{}
+		label, fallback := extractLabel(header)
+		a.Equal("", label)
+		a.True(fallback)
+
+		// X-Canary: dev
+		header.Set("X-Canary", "dev")
+		label, fallback = extractLabel(header)
+		a.Equal("dev", label)
+		a.True(fallback)
+
+		// X-Canary: label=beta,product=urbs,uid=5c4057f0be825b390667abee,nofallback ...
+		header = http.Header{}
+		header.Set("X-Canary", "label=beta,product=urbs,uid=5c4057f0be825b390667abee,nofallback")
+		label, fallback = extractLabel(header)
+		a.Equal("beta", label)
+		a.False(fallback)
+
+		header = http.Header{}
+		header.Set("X-Canary", "label=dev,product=urbs,uid=5c4057f0be825b390667abee")
+		label, fallback = extractLabel(header)
+		a.Equal("dev", label)
+		a.True(fallback)
+
+		header = http.Header{}
+		header.Set("X-Canary", "product=urbs,uid=5c4057f0be825b390667abee,nofallback,label=dev")
+		label, fallback = extractLabel(header)
+		a.Equal("dev", label)
+		a.False(fallback)
+
+		// X-Canary: label=beta; product=urbs; uid=5c4057f0be825b390667abee; nofallback ...
+		header = http.Header{}
+		header.Set("X-Canary", "label=beta; product=urbs; uid=5c4057f0be825b390667abee; nofallback")
+		label, fallback = extractLabel(header)
+		a.Equal("beta", label)
+		a.False(fallback)
+
+		header = http.Header{}
+		header.Add("X-Canary", "label=beta")
+		header.Add("X-Canary", "product=urbs")
+		header.Add("X-Canary", "uid=5c4057f0be825b390667abee")
+		header.Add("X-Canary", "nofallback")
+		label, fallback = extractLabel(header)
+		a.Equal("beta", label)
+		a.False(fallback)
+	})
 }