/*
 * Copyright 1999-2018 Alibaba Group Holding Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.csp.sentinel.dashboard.rule.zookeeper;

import com.alibaba.csp.sentinel.dashboard.datasource.entity.rule.FlowRuleEntity;
import com.alibaba.csp.sentinel.dashboard.rule.DynamicRuleProvider;
import com.alibaba.csp.sentinel.datasource.Converter;
import org.apache.curator.framework.CuratorFramework;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.List;

@Component("flowRuleZookeeperProvider")
public class FlowRuleZookeeperProvider implements DynamicRuleProvider<List<FlowRuleEntity>> {

    @Autowired
    private CuratorFramework zkClient;
    @Autowired
    private Converter<String, List<FlowRuleEntity>> converter;

    @Override
    public List<FlowRuleEntity> getRules(String appName) throws Exception {
        String zkPath = ZookeeperConfigUtil.getPath(appName);
        byte[] bytes = zkClient.getData().forPath(zkPath);
        if (null == bytes || bytes.length == 0) {
            return new ArrayList<>();
        }
        String s = new String(bytes);

        return converter.convert(s);
    }
}
@@ -926,16 +926,55 @@
 mework;%0A
+import org.apache.zookeeper.data.Stat;%0A
 import o
@@ -1550,16 +1550,151 @@
 pName);%0A
+        Stat stat = zkClient.checkExists().forPath(zkPath);%0A        if(stat == null)%7B%0A            return new ArrayList%3C%3E(0);%0A        %7D%0A
         

Fix NoNodeException problem of FlowRuleZookeeperProvider example (#1352)