ZKDiscoveryService: fix potential outdated server info on recalculatePartitions. info logs added on application event

common/queue/src/main/java/org/thingsboard/server/queue/discovery/ZkDiscoveryService.java

@@ -125,8 +125,10 @@ public class ZkDiscoveryService implements DiscoveryService, PathChildrenCacheLi
             log.debug("Ignoring application ready event, ZK client is not started, ZK client state [{}]", client.getState());
             return;
         }
+        log.info("Going to publish current server...");
         publishCurrentServer();
-        partitionService.recalculatePartitions(serviceInfoProvider.getServiceInfo(), getOtherServers());
+        log.info("Going to recalculate partitions...");
+        recalculatePartitions();
     }
 
     public synchronized void publishCurrentServer() {
@@ -281,11 +283,19 @@ public class ZkDiscoveryService implements DiscoveryService, PathChildrenCacheLi
             case CHILD_ADDED:
             case CHILD_UPDATED:
             case CHILD_REMOVED:
-                partitionService.recalculatePartitions(serviceInfoProvider.getServiceInfo(), getOtherServers());
+                recalculatePartitions();
                 break;
             default:
                 break;
         }
     }
 
+    /**
+     * A single entry point to recalculate partitions
+     * Synchronized to ensure that other servers info is up to date
+     * */
+    synchronized void recalculatePartitions() {
+        partitionService.recalculatePartitions(serviceInfoProvider.getServiceInfo(), getOtherServers());
+    }
+
 }