Fixed ordering for available notification delivery methods

application/src/main/java/org/thingsboard/server/controller/NotificationController.java

@@ -477,7 +477,7 @@ public class NotificationController extends BaseController {
                     SYSTEM_OR_TENANT_AUTHORITY_PARAGRAPH)
     @GetMapping("/notification/deliveryMethods")
     @PreAuthorize("hasAnyAuthority('SYS_ADMIN', 'TENANT_ADMIN', 'CUSTOMER_USER')")
-    public Set<NotificationDeliveryMethod> getAvailableDeliveryMethods(@AuthenticationPrincipal SecurityUser user) throws ThingsboardException {
+    public List<NotificationDeliveryMethod> getAvailableDeliveryMethods(@AuthenticationPrincipal SecurityUser user) throws ThingsboardException {
         return notificationCenter.getAvailableDeliveryMethods(user.getTenantId());
     }
 

application/src/main/java/org/thingsboard/server/service/notification/DefaultNotificationCenter.java

@@ -417,7 +417,7 @@ public class DefaultNotificationCenter extends AbstractSubscriptionService imple
     }
 
     @Override
-    public Set<NotificationDeliveryMethod> getAvailableDeliveryMethods(TenantId tenantId) {
+    public List<NotificationDeliveryMethod> getAvailableDeliveryMethods(TenantId tenantId) {
         return channels.values().stream()
                 .filter(channel -> {
                     try {
@@ -428,7 +428,7 @@ public class DefaultNotificationCenter extends AbstractSubscriptionService imple
                     }
                 })
                 .map(NotificationChannel::getDeliveryMethod)
-                .collect(Collectors.toSet());
+                .sorted().toList();
     }
 
     @Override

rule-engine/rule-engine-api/src/main/java/org/thingsboard/rule/engine/api/NotificationCenter.java

@@ -30,7 +30,7 @@ import org.thingsboard.server.common.data.notification.info.NotificationInfo;
 import org.thingsboard.server.common.data.notification.targets.platform.UsersFilter;
 import org.thingsboard.server.common.data.notification.template.NotificationTemplate;
 
-import java.util.Set;
+import java.util.List;
 
 public interface NotificationCenter {
 
@@ -48,6 +48,6 @@ public interface NotificationCenter {
 
     void deleteNotification(TenantId tenantId, UserId recipientId, NotificationId notificationId);
 
-    Set<NotificationDeliveryMethod> getAvailableDeliveryMethods(TenantId tenantId);
+    List<NotificationDeliveryMethod> getAvailableDeliveryMethods(TenantId tenantId);
 
 }