make delivery mode persistent by default

pool/session.go

@@ -275,7 +275,7 @@ type Publishing struct {
 	// Properties
 	ContentType     string    // MIME content type
 	ContentEncoding string    // MIME content encoding
-	DeliveryMode    uint8     // Transient (0 or 1) or Persistent (2)
+	DeliveryMode    uint8     // Persistent (0 or 2) or Transient (1) (different from rabbitmq/amqp091-go library)
 	Priority        uint8     // 0 to 9
 	CorrelationId   string    // correlation identifier
 	ReplyTo         string    // address to to reply to (ex: RPC)
@@ -310,6 +310,17 @@ func (s *Session) Publish(ctx context.Context, exchange string, routingKey strin
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
+	// we want to have a persistent messages by default
+	// this allows to even in a disaster case where the rabbitmq node is restarted or crashes
+	// to still have our messages persisted to disk.
+	// https://www.rabbitmq.com/persistence-conf.html#how-it-works
+	var amqpDeliverMode uint8
+	if msg.DeliveryMode == 1 {
+		amqpDeliverMode = 1 // transient (purged upon rabbitmq restart)
+	} else {
+		amqpDeliverMode = 2 // persistent (persisted to disk upon arrival in queue)
+	}
+
 	return s.retryPublish(func() (uint64, error) {
 		tag = 0
 		if s.confirmable {
@@ -326,7 +337,7 @@ func (s *Session) Publish(ctx context.Context, exchange string, routingKey strin
 				Headers:         msg.Headers,
 				ContentType:     msg.ContentType,
 				ContentEncoding: msg.ContentEncoding,
-				DeliveryMode:    msg.DeliveryMode,
+				DeliveryMode:    amqpDeliverMode,
 				Priority:        msg.Priority,
 				CorrelationId:   msg.CorrelationId,
 				ReplyTo:         msg.ReplyTo,