add kafka topic/partition/offset to the extension of event

protocol/kafka_sarama/v2/message.go

@@ -8,6 +8,7 @@ package kafka_sarama
 import (
 	"bytes"
 	"context"
+	"strconv"
 	"strings"
 
 	"github.com/cloudevents/sdk-go/v2/binding"
@@ -35,22 +36,27 @@ type Message struct {
 }
 
 // Check if http.Message implements binding.Message
-var _ binding.Message = (*Message)(nil)
-var _ binding.MessageMetadataReader = (*Message)(nil)
+var (
+	_ binding.Message               = (*Message)(nil)
+	_ binding.MessageMetadataReader = (*Message)(nil)
+)
 
 // NewMessageFromConsumerMessage returns a binding.Message that holds the provided ConsumerMessage.
 // The returned binding.Message *can* be read several times safely
 // This function *doesn't* guarantee that the returned binding.Message is always a kafka_sarama.Message instance
 func NewMessageFromConsumerMessage(cm *sarama.ConsumerMessage) *Message {
 	var contentType string
-	headers := make(map[string][]byte, len(cm.Headers))
+	headers := make(map[string][]byte, len(cm.Headers)+3)
 	for _, r := range cm.Headers {
 		k := strings.ToLower(string(r.Key))
 		if k == contentTypeHeader {
 			contentType = string(r.Value)
 		}
 		headers[k] = r.Value
 	}
+	headers[prefix+"kafkaoffset"] = []byte(strconv.FormatInt(cm.Offset, 10))
+	headers[prefix+"kafkapartition"] = []byte(strconv.FormatInt(int64(cm.Partition), 10))
+	headers[prefix+"kafkatopic"] = []byte(cm.Topic)
 	return NewMessage(cm.Value, contentType, headers)
 }
 

test/integration/kafka_sarama/kafka_test.go

@@ -21,16 +21,30 @@ import (
 )
 
 const (
-	TEST_GROUP_ID = "test_group_id"
+	TEST_GROUP_ID   = "test_group_id"
+	KAFKA_OFFSET    = "kafkaoffset"
+	KAFKA_PARTITION = "kafkapartition"
+	KAFKA_TOPIC     = "kafkatopic"
 )
 
+var TopicName = "test-ce-client-" + uuid.New().String()
+
 func TestSendEvent(t *testing.T) {
 	test.EachEvent(t, test.Events(), func(t *testing.T, eventIn event.Event) {
 		eventIn = test.ConvertEventExtensionsToString(t, eventIn)
 		clienttest.SendReceive(t, func() interface{} {
 			return protocolFactory(t)
-		}, eventIn, func(e event.Event) {
-			test.AssertEventEquals(t, eventIn, test.ConvertEventExtensionsToString(t, e))
+		}, eventIn, func(eventOut event.Event) {
+			eventOut = test.ConvertEventExtensionsToString(t, eventOut)
+
+			require.Equal(t, TopicName, eventOut.Extensions()[KAFKA_TOPIC])
+			require.NotNil(t, eventOut.Extensions()[KAFKA_PARTITION])
+			require.NotNil(t, eventOut.Extensions()[KAFKA_OFFSET])
+
+			test.AllOf(
+				test.HasExactlyAttributesEqualTo(eventIn.Context),
+				test.HasData(eventIn.Data()),
+			)
 		})
 	})
 }
@@ -60,11 +74,10 @@ func testClient(t testing.TB) sarama.Client {
 func protocolFactory(t testing.TB) *kafka_sarama.Protocol {
 	client := testClient(t)
 
-	topicName := "test-ce-client-" + uuid.New().String()
 	options := []kafka_sarama.ProtocolOptionFunc{
 		kafka_sarama.WithReceiverGroupId(TEST_GROUP_ID),
 	}
-	p, err := kafka_sarama.NewProtocolFromClient(client, topicName, topicName, options...)
+	p, err := kafka_sarama.NewProtocolFromClient(client, TopicName, TopicName, options...)
 	require.NoError(t, err)
 
 	return p

test/integration/kafka_sarama_binding/kafka_test.go

@@ -27,11 +27,14 @@ import (
 )
 
 const (
-	TEST_GROUP_ID = "test_group_id"
+	TEST_GROUP_ID   = "test_group_id"
+	KAFKA_OFFSET    = "kafkaoffset"
+	KAFKA_PARTITION = "kafkapartition"
+	KAFKA_TOPIC     = "kafkatopic"
 )
 
 func TestSendStructuredMessageToStructured(t *testing.T) {
-	close, s, r := testSenderReceiver(t)
+	close, s, r, _ := testSenderReceiver(t)
 	defer close()
 	EachEvent(t, Events(), func(t *testing.T, eventIn event.Event) {
 		eventIn = ConvertEventExtensionsToString(t, eventIn)
@@ -46,7 +49,7 @@ func TestSendStructuredMessageToStructured(t *testing.T) {
 }
 
 func TestSendBinaryMessageToBinary(t *testing.T) {
-	close, s, r := testSenderReceiver(t)
+	close, s, r, topicName := testSenderReceiver(t)
 	defer close()
 	EachEvent(t, Events(), func(t *testing.T, eventIn event.Event) {
 		eventIn = ConvertEventExtensionsToString(t, eventIn)
@@ -55,7 +58,16 @@ func TestSendBinaryMessageToBinary(t *testing.T) {
 		test.SendReceive(t, binding.WithPreferredEventEncoding(context.TODO(), binding.EncodingBinary), in, s, r, func(out binding.Message) {
 			eventOut := MustToEvent(t, context.Background(), out)
 			assert.Equal(t, binding.EncodingBinary, out.ReadEncoding())
-			AssertEventEquals(t, eventIn, ConvertEventExtensionsToString(t, eventOut))
+			eventOut = ConvertEventExtensionsToString(t, eventOut)
+
+			require.Equal(t, topicName, eventOut.Extensions()[KAFKA_TOPIC])
+			require.NotNil(t, eventOut.Extensions()[KAFKA_PARTITION])
+			require.NotNil(t, eventOut.Extensions()[KAFKA_OFFSET])
+
+			AllOf(
+				HasExactlyAttributesEqualTo(eventIn.Context),
+				HasData(eventIn.Data()),
+			)
 		})
 	})
 }
@@ -82,7 +94,7 @@ func testClient(t testing.TB) sarama.Client {
 	return client
 }
 
-func testSenderReceiver(t testing.TB) (func(), bindings.Sender, bindings.Receiver) {
+func testSenderReceiver(t testing.TB) (func(), bindings.Sender, bindings.Receiver, string) {
 	client := testClient(t)
 
 	topicName := "test-ce-client-" + uuid.New().String()
@@ -97,11 +109,11 @@ func testSenderReceiver(t testing.TB) (func(), bindings.Sender, bindings.Receive
 	return func() {
 		require.NoError(t, p.Close(context.TODO()))
 		require.NoError(t, client.Close())
-	}, p, p
+	}, p, p, topicName
 }
 
 func BenchmarkSendReceive(b *testing.B) {
-	c, s, r := testSenderReceiver(b)
+	c, s, r, _ := testSenderReceiver(b)
 	defer c() // Cleanup
 	test.BenchmarkSendReceive(b, s, r)
 }