FIX: Redis to handle event metadata. (#3320)

Signed-off-by: Artur Souza <asouza.pro@gmail.com>
Signed-off-by: Bernd Verst <github@bernd.dev>
Co-authored-by: Bernd Verst <github@bernd.dev>

pubsub/redis/redis.go

@@ -15,6 +15,7 @@ package redis
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"reflect"
@@ -101,7 +102,17 @@ func (r *redisStreams) Publish(ctx context.Context, req *pubsub.PublishRequest)
 		return errors.New("component is closed")
 	}
 
-	_, err := r.client.XAdd(ctx, req.Topic, r.clientSettings.MaxLenApprox, map[string]interface{}{"data": req.Data})
+	redisPayload := map[string]interface{}{"data": req.Data}
+
+	if req.Metadata != nil {
+		serializedMetadata, err := json.Marshal(req.Metadata)
+		if err != nil {
+			return err
+		}
+		redisPayload["metadata"] = serializedMetadata
+	}
+
+	_, err := r.client.XAdd(ctx, req.Topic, r.clientSettings.MaxLenApprox, redisPayload)
 	if err != nil {
 		return fmt.Errorf("redis streams: error from publish: %s", err)
 	}
@@ -157,7 +168,7 @@ func (r *redisStreams) Subscribe(ctx context.Context, req pubsub.SubscribeReques
 // pick them up for processing.
 func (r *redisStreams) enqueueMessages(ctx context.Context, stream string, handler pubsub.Handler, msgs []rediscomponent.RedisXMessage) {
 	for _, msg := range msgs {
-		rmsg := createRedisMessageWrapper(ctx, stream, handler, msg)
+		rmsg := r.createRedisMessageWrapper(ctx, stream, handler, msg)
 
 		select {
 		// Might block if the queue is full so we need the ctx.Done below.
@@ -172,7 +183,7 @@ func (r *redisStreams) enqueueMessages(ctx context.Context, stream string, handl
 
 // createRedisMessageWrapper encapsulates the Redis message, message identifier, and handler
 // in `redisMessage` for processing.
-func createRedisMessageWrapper(ctx context.Context, stream string, handler pubsub.Handler, msg rediscomponent.RedisXMessage) redisMessageWrapper {
+func (r *redisStreams) createRedisMessageWrapper(ctx context.Context, stream string, handler pubsub.Handler, msg rediscomponent.RedisXMessage) redisMessageWrapper {
 	var data []byte
 	if dataValue, exists := msg.Values["data"]; exists && dataValue != nil {
 		switch v := dataValue.(type) {
@@ -183,11 +194,21 @@ func createRedisMessageWrapper(ctx context.Context, stream string, handler pubsu
 		}
 	}
 
+	var metadata map[string]string
+	if metadataValue, exists := msg.Values["metadata"]; exists && metadataValue != nil {
+		metadataStr := metadataValue.(string)
+		err := json.Unmarshal([]byte(metadataStr), &metadata)
+		if err != nil {
+			r.logger.Warnf("Redis PubSub: Could not extract metadata for Redis message %s: %v", msg.ID, err)
+		}
+	}
+
 	return redisMessageWrapper{
 		ctx: ctx,
 		message: pubsub.NewMessage{
-			Topic: stream,
-			Data:  data,
+			Topic:    stream,
+			Data:     data,
+			Metadata: metadata,
 		},
 		messageID: msg.ID,
 		handler:   handler,

pubsub/redis/redis_test.go

@@ -76,9 +76,9 @@ func TestParseRedisMetadata(t *testing.T) {
 
 func TestProcessStreams(t *testing.T) {
 	fakeConsumerID := "fakeConsumer"
-	topicCount := 0
 	messageCount := 0
 	expectedData := "testData"
+	expectedMetadata := "testMetadata"
 
 	var wg sync.WaitGroup
 	wg.Add(3)
@@ -87,12 +87,10 @@ func TestProcessStreams(t *testing.T) {
 		defer wg.Done()
 
 		messageCount++
-		if topicCount == 0 {
-			topicCount = 1
-		}
 
 		// assert
 		assert.Equal(t, expectedData, string(msg.Data))
+		assert.Equal(t, expectedMetadata, msg.Metadata["mymetadata"])
 
 		// return fake error to skip executing redis client command
 		return errors.New("fake error")
@@ -105,23 +103,66 @@ func TestProcessStreams(t *testing.T) {
 	}
 	testRedisStream.queue = make(chan redisMessageWrapper, 10)
 	go testRedisStream.worker()
-	testRedisStream.enqueueMessages(context.Background(), fakeConsumerID, fakeHandler, generateRedisStreamTestData(2, 3, expectedData))
+	testRedisStream.enqueueMessages(context.Background(), fakeConsumerID, fakeHandler, generateRedisStreamTestData(3, expectedData, expectedMetadata))
 
 	// Wait for the handler to finish processing
 	wg.Wait()
 
 	// assert
-	assert.Equal(t, 1, topicCount)
 	assert.Equal(t, 3, messageCount)
 }
 
-func generateRedisStreamTestData(topicCount, messageCount int, data string) []commonredis.RedisXMessage {
+func TestProcessStreamsWithoutEventMetadata(t *testing.T) {
+	fakeConsumerID := "fakeConsumer"
+	messageCount := 0
+	expectedData := "testData"
+
+	var wg sync.WaitGroup
+	wg.Add(3)
+
+	fakeHandler := func(ctx context.Context, msg *pubsub.NewMessage) error {
+		defer wg.Done()
+
+		messageCount++
+
+		// assert
+		assert.Equal(t, expectedData, string(msg.Data))
+
+		assert.Nil(t, msg.Metadata)
+
+		// return fake error to skip executing redis client command
+		return errors.New("fake error")
+	}
+
+	// act
+	testRedisStream := &redisStreams{
+		logger:         logger.NewLogger("test"),
+		clientSettings: &commonredis.Settings{},
+	}
+	testRedisStream.queue = make(chan redisMessageWrapper, 10)
+	go testRedisStream.worker()
+	testRedisStream.enqueueMessages(context.Background(), fakeConsumerID, fakeHandler, generateRedisStreamTestData(3, expectedData, ""))
+
+	// Wait for the handler to finish processing
+	wg.Wait()
+
+	// assert
+	assert.Equal(t, 3, messageCount)
+}
+
+func generateRedisStreamTestData(messageCount int, data string, metadata string) []commonredis.RedisXMessage {
 	generateXMessage := func(id int) commonredis.RedisXMessage {
+		values := map[string]interface{}{
+			"data": data,
+		}
+
+		if metadata != "" {
+			values["metadata"] = "{\"mymetadata\": \"" + metadata + "\"}"
+		}
+
 		return commonredis.RedisXMessage{
-			ID: strconv.Itoa(id),
-			Values: map[string]interface{}{
-				"data": data,
-			},
+			ID:     strconv.Itoa(id),
+			Values: values,
 		}
 	}