[WIP] Illustrate problem with baggage values

baggage/baggage.go

@@ -254,6 +254,9 @@ type Member struct {
 // used directly while the value will be url decoded after validation. An error
 // is returned if the created Member would be invalid according to the W3C
 // Baggage specification.
+//
+// Note: value must be encoded via url.QueryEscape(). But Value() will return
+// the unencoded value (inconsistency).
 func NewMember(key, value string, props ...Property) (Member, error) {
 	m := Member{
 		key:        key,
@@ -312,15 +315,16 @@ func parseMember(member string) (Member, error) {
 		// "Leading and trailing whitespaces are allowed but MUST be trimmed
 		// when converting the header into a data structure."
 		key = strings.TrimSpace(kv[0])
+		valueEscaped := strings.TrimSpace(kv[1])
 		var err error
-		value, err = url.QueryUnescape(strings.TrimSpace(kv[1]))
+		value, err = url.QueryUnescape(valueEscaped)
 		if err != nil {
 			return newInvalidMember(), fmt.Errorf("%w: %q", err, value)
 		}
 		if !keyRe.MatchString(key) {
 			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
 		}
-		if !valueRe.MatchString(value) {
+		if !valueRe.MatchString(valueEscaped) {
 			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
 		}
 	default:

baggage/baggage_test.go

@@ -345,9 +345,9 @@ func TestBaggageParse(t *testing.T) {
 		},
 		{
 			name: "url encoded value",
-			in:   "key1=val%252",
+			in:   "key1=val+%27+2",
 			want: baggage.List{
-				"key1": {Value: "val%2"},
+				"key1": {Value: "val ' 2"},
 			},
 		},
 		{
@@ -406,7 +406,7 @@ func TestBaggageParse(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			actual, err := Parse(tc.in)
 			assert.ErrorIs(t, err, tc.err)
-			assert.Equal(t, Baggage{list: tc.want}, actual)
+			assert.Equal(t, Baggage{list: tc.want}, actual, "and error=%v", err)
 		})
 	}
 }

bridge/opentracing/bridge.go

@@ -18,6 +18,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"net/url"
 	"strings"
 	"sync"
 
@@ -74,7 +75,7 @@ func (c *bridgeSpanContext) ForeachBaggageItem(handler func(k, v string) bool) {
 
 func (c *bridgeSpanContext) setBaggageItem(restrictedKey, value string) {
 	crk := http.CanonicalHeaderKey(restrictedKey)
-	m, err := baggage.NewMember(crk, value)
+	m, err := baggage.NewMember(crk, url.QueryEscape(value))
 	if err != nil {
 		return
 	}

bridge/opentracing/mix_test.go

@@ -17,6 +17,7 @@ package opentracing
 import (
 	"context"
 	"fmt"
+	"net/url"
 	"testing"
 
 	ot "github.com/opentracing/opentracing-go"
@@ -109,19 +110,20 @@ func getMixedAPIsTestCases() []mixedAPIsTestCase {
 
 func TestMixedAPIs(t *testing.T) {
 	for idx, tc := range getMixedAPIsTestCases() {
-		t.Logf("Running test case %d: %s", idx, tc.desc)
-		mockOtelTracer := internal.NewMockTracer()
-		ctx, otTracer, otelProvider := NewTracerPairWithContext(context.Background(), mockOtelTracer)
-		otTracer.SetWarningHandler(func(msg string) {
-			t.Log(msg)
+		t.Run(fmt.Sprintf("Running test case %d: %s", idx, tc.desc), func(t *testing.T) {
+			mockOtelTracer := internal.NewMockTracer()
+			ctx, otTracer, otelProvider := NewTracerPairWithContext(context.Background(), mockOtelTracer)
+			otTracer.SetWarningHandler(func(msg string) {
+				t.Log(msg)
+			})
+
+			otel.SetTracerProvider(otelProvider)
+			ot.SetGlobalTracer(otTracer)
+
+			tc.setup(t, mockOtelTracer)
+			tc.run(t, ctx)
+			tc.check(t, mockOtelTracer)
 		})
-
-		otel.SetTracerProvider(otelProvider)
-		ot.SetGlobalTracer(otTracer)
-
-		tc.setup(t, mockOtelTracer)
-		tc.run(t, ctx)
-		tc.check(t, mockOtelTracer)
 	}
 }
 
@@ -335,7 +337,7 @@ func newBaggageItemsPreservationTest() *baggageItemsPreservationTest {
 			},
 			{
 				key:   "Third",
-				value: "three",
+				value: "three space four", // not URL-encoded
 			},
 		},
 	}
@@ -428,7 +430,7 @@ func newBaggageInteroperationTest() *baggageInteroperationTest {
 			},
 			{
 				key:   "Third",
-				value: "three",
+				value: "three space four", // not URL-encoded
 			},
 		},
 	}
@@ -515,7 +517,7 @@ func (bio *baggageInteroperationTest) addAndRecordBaggage(t *testing.T, ctx cont
 
 	otSpan.SetBaggageItem(otKey, value)
 
-	m, err := baggage.NewMember(otelKey, value)
+	m, err := baggage.NewMember(otelKey, url.QueryEscape(value))
 	if err != nil {
 		t.Error(err)
 		return ctx