From b6ab568d9b0a4b10ffb4b87902fbe2ce896e3240 Mon Sep 17 00:00:00 2001
From: Tboy <technoboy@yeah.net>
Date: Sun, 20 Oct 2019 23:16:34 +0800
Subject: [PATCH] delete before check to avoid KeeperException$NoNodeException
 (#1062)

* move updateTaskState into try/catch block in case of exception

* fix NPE

* using conf.getInt instead of getString

* for AbstractZKClient, remove the log, for it will print the same log message in createZNodePath.
for AlertDao, correct the spelling.

* duplicate

* refactor getTaskWorkerGroupId

* add friendly log

* update hearbeat thread num = 1

* fix the bug when worker execute task using queue. and remove checking Tenant user anymore in TaskScheduleThread

* 1. move verifyTaskInstanceIsNull after taskInstance
2. keep verifyTenantIsNull/verifyTaskInstanceIsNull clean and readable

* fix the message

* delete before check to avoid KeeperException$NoNodeException
---
 .../apache/dolphinscheduler/common/zk/AbstractZKClient.java | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/zk/AbstractZKClient.java b/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/zk/AbstractZKClient.java
index 383c156e51..ec33575670 100644
--- a/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/zk/AbstractZKClient.java
+++ b/dolphinscheduler-common/src/main/java/org/apache/dolphinscheduler/common/zk/AbstractZKClient.java
@@ -201,8 +201,10 @@ public abstract class AbstractZKClient {
         for(String serverPath : deadServers){
             if(serverPath.startsWith(serverType+UNDERLINE+host)){
 				String server = getDeadZNodeParentPath() + SINGLE_SLASH + serverPath;
-				zkClient.delete().forPath(server);
-                logger.info("{} server {} deleted from zk dead server path success" , serverType , host);
+				if(zkClient.checkExists().forPath(server) != null){
+					zkClient.delete().forPath(server);
+					logger.info("{} server {} deleted from zk dead server path success" , serverType , host);
+				}
             }
         }
 	}