[IMPROVED] MQTT: Retained msgs handling with cross account and transform

server/client.go

@@ -3022,7 +3022,7 @@ func (c *client) processSubEx(subject, queue, bsid []byte, cb msgHandler, noForw
 		return sub, nil
 	}
 
-	if err := c.addShadowSubscriptions(acc, sub, true); err != nil {
+	if err := c.addShadowSubscriptions(acc, sub); err != nil {
 		c.Errorf(err.Error())
 	}
 
@@ -3052,10 +3052,7 @@ type ime struct {
 // If the client's account has stream imports and there are matches for this
 // subscription's subject, then add shadow subscriptions in the other accounts
 // that export this subject.
-//
-// enact=false allows MQTT clients to get the list of shadow subscriptions
-// without enacting them, in order to first obtain matching "retained" messages.
-func (c *client) addShadowSubscriptions(acc *Account, sub *subscription, enact bool) error {
+func (c *client) addShadowSubscriptions(acc *Account, sub *subscription) error {
 	if acc == nil {
 		return ErrMissingAccount
 	}
@@ -3158,7 +3155,7 @@ func (c *client) addShadowSubscriptions(acc *Account, sub *subscription, enact b
 	for i := 0; i < len(ims); i++ {
 		ime := &ims[i]
 		// We will create a shadow subscription.
-		nsub, err := c.addShadowSub(sub, ime, enact)
+		nsub, err := c.addShadowSub(sub, ime)
 		if err != nil {
 			return err
 		}
@@ -3175,7 +3172,7 @@ func (c *client) addShadowSubscriptions(acc *Account, sub *subscription, enact b
 }
 
 // Add in the shadow subscription.
-func (c *client) addShadowSub(sub *subscription, ime *ime, enact bool) (*subscription, error) {
+func (c *client) addShadowSub(sub *subscription, ime *ime) (*subscription, error) {
 	c.mu.Lock()
 	nsub := *sub // copy
 	c.mu.Unlock()
@@ -3203,10 +3200,6 @@ func (c *client) addShadowSub(sub *subscription, ime *ime, enact bool) (*subscri
 	}
 	// Else use original subject
 
-	if !enact {
-		return &nsub, nil
-	}
-
 	c.Debugf("Creating import subscription on %q from account %q", nsub.subject, im.acc.Name)
 
 	if err := im.acc.sl.Insert(&nsub); err != nil {
@@ -5796,7 +5789,7 @@ func (c *client) processSubsOnConfigReload(awcsti map[string]struct{}) {
 		oldShadows := sub.shadow
 		sub.shadow = nil
 		c.mu.Unlock()
-		c.addShadowSubscriptions(acc, sub, true)
+		c.addShadowSubscriptions(acc, sub)
 		for _, nsub := range oldShadows {
 			nsub.im.acc.sl.Remove(nsub)
 		}

server/leafnode.go

@@ -2832,7 +2832,7 @@ func (c *client) processLeafSub(argo []byte) (err error) {
 
 	// Only add in shadow subs if a new sub or qsub.
 	if osub == nil {
-		if err := c.addShadowSubscriptions(acc, sub, true); err != nil {
+		if err := c.addShadowSubscriptions(acc, sub); err != nil {
 			c.Errorf(err.Error())
 		}
 	}