chore: update README

Signed-off-by: Eray Ates <[email protected]>

README.md

@@ -99,8 +99,10 @@ if err != nil {
 defer client.Close()
 ```
 
-Now you need to run consumer with a handler function.  
-There is 2 options to run consumer, batch or single (__WithCallbackBatch__ or __WithCallback__).
+Now you need to run consumer with a callback function.  
+There is 2 options to run consumer, batch or single (__WithCallbackBatch__ or __WithCallback__).  
+Default decoder is json, but you can change it with __WithDecode__ option.  
+If you use `[]byte` as data type then raw data will be passed to the callback function, batch consumer like `[][]byte` type.
 
 ```go
 // example single consumer

example/consumer/byte.go

@@ -0,0 +1,38 @@
+package consumer
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"sync"
+
+	"github.com/worldline-go/wkafka"
+)
+
+func ProcessSingleByte(ctx context.Context, raw []byte) error {
+	var msg DataSingle
+	if err := json.Unmarshal(raw, &msg); err != nil {
+		return err
+	}
+
+	return ProcessSingle(ctx, msg)
+}
+
+func RunExampleSingleByte(ctx context.Context, _ *sync.WaitGroup) error {
+	client, err := wkafka.New(
+		ctx, kafkaConfigSingle,
+		wkafka.WithConsumer(consumeConfigSingle),
+		wkafka.WithClientInfo("testapp", "v0.1.0"),
+	)
+	if err != nil {
+		return err
+	}
+
+	defer client.Close()
+
+	if err := client.Consume(ctx, wkafka.WithCallback(ProcessSingleByte)); err != nil {
+		return fmt.Errorf("consume: %w", err)
+	}
+
+	return nil
+}

example/main.go

@@ -15,12 +15,13 @@ import (
 )
 
 var examples = map[string]func(context.Context, *sync.WaitGroup) error{
-	"admin_topic":     admin.RunExampleTopic,
-	"admin_partition": admin.RunExamplePartition,
-	"admin_list":      admin.RunExampleList,
-	"consumer_batch":  consumer.RunExampleBatch,
-	"consumer_single": consumer.RunExampleSingle,
-	"producer_hook":   producer.RunExampleHook,
+	"admin_topic":          admin.RunExampleTopic,
+	"admin_partition":      admin.RunExamplePartition,
+	"admin_list":           admin.RunExampleList,
+	"consumer_batch":       consumer.RunExampleBatch,
+	"consumer_single":      consumer.RunExampleSingle,
+	"consumer_single_byte": consumer.RunExampleSingleByte,
+	"producer_hook":        producer.RunExampleHook,
 }
 
 func getExampleList() []string {