Skip processing consumer assignments after JS has shutdown (#4625)

Signed-off-by: Waldemar Quevedo <wally@nats.io>

server/consumer.go

@@ -1593,6 +1593,10 @@ func (o *consumer) deleteNotActive() {
 				defer ticker.Stop()
 				for range ticker.C {
 					js.mu.RLock()
+					if js.shuttingDown {
+						js.mu.RUnlock()
+						return
+					}
 					nca := js.consumerAssignment(acc, stream, name)
 					js.mu.RUnlock()
 					// Make sure this is not a new consumer with the same name.

server/jetstream_cluster.go

@@ -2705,6 +2705,11 @@ func (mset *stream) resetClusteredState(err error) bool {
 
 		if sa != nil {
 			js.mu.Lock()
+			if js.shuttingDown {
+				js.mu.Unlock()
+				return
+			}
+
 			s.Warnf("Resetting stream cluster state for '%s > %s'", sa.Client.serviceAccount(), sa.Config.Name)
 			// Now wipe groups from assignments.
 			sa.Group.node = nil
@@ -3893,6 +3898,7 @@ func (js *jetStream) processConsumerAssignment(ca *consumerAssignment) {
 	s, cc := js.srv, js.cluster
 	accName, stream, consumerName := ca.Client.serviceAccount(), ca.Stream, ca.Name
 	noMeta := cc == nil || cc.meta == nil
+	shuttingDown := js.shuttingDown
 	var ourID string
 	if !noMeta {
 		ourID = cc.meta.ID()
@@ -3903,7 +3909,7 @@ func (js *jetStream) processConsumerAssignment(ca *consumerAssignment) {
 	}
 	js.mu.RUnlock()
 
-	if s == nil || noMeta {
+	if s == nil || noMeta || shuttingDown {
 		return
 	}