pass errors from broker to subscribers

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

kgo.go

@@ -112,6 +112,7 @@ type kgoMessage struct {
 	hdr   metadata.Metadata
 	opts  broker.MessageOptions
 	ack   bool
+	err   error
 }
 
 func (m *kgoMessage) Ack() error {
@@ -135,6 +136,10 @@ func (m *kgoMessage) Topic() string {
 	return ""
 }
 
+func (m *kgoMessage) Error() error {
+	return m.err
+}
+
 func (m *kgoMessage) Unmarshal(dst interface{}, opts ...codec.Option) error {
 	return m.c.Unmarshal(m.body, dst)
 }
@@ -519,15 +524,6 @@ func (b *Broker) fnSubscribe(ctx context.Context, topic string, handler interfac
 
 	options := broker.NewSubscribeOptions(opts...)
 
-	switch handler.(type) {
-	default:
-		return nil, broker.ErrInvalidHandler
-	case func(broker.Message) error:
-		break
-	case func([]broker.Message) error:
-		break
-	}
-
 	if options.Group == "" {
 		uid, err := id.New()
 		if err != nil {
@@ -584,6 +580,7 @@ func (b *Broker) fnSubscribe(ctx context.Context, topic string, handler interfac
 		kgo.OnPartitionsLost(sub.lost),
 		kgo.AutoCommitCallback(sub.autocommit),
 		kgo.AutoCommitMarks(),
+		kgo.WithHooks(sub),
 	)
 
 	if options.Context != nil {