narendly commented on a change in pull request #727: Add MetadataStoreRoutingDataWriter with DistributedLeaderElection URL: https://github.com/apache/helix/pull/727#discussion_r377341935
########## File path: helix-rest/src/main/java/org/apache/helix/rest/metadatastore/accessor/ZkRoutingDataWriter.java ########## @@ -0,0 +1,253 @@ +package org.apache.helix.rest.metadatastore.accessor; + +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + */ + +import java.util.Collections; +import java.util.List; +import java.util.Map; + +import org.I0Itec.zkclient.exception.ZkNodeExistsException; +import org.apache.helix.ZNRecord; +import org.apache.helix.manager.zk.ZNRecordSerializer; +import org.apache.helix.manager.zk.ZkBaseDataAccessor; +import org.apache.helix.manager.zk.client.DedicatedZkClientFactory; +import org.apache.helix.manager.zk.client.HelixZkClient; +import org.apache.helix.rest.metadatastore.concurrency.ZkDistributedLeaderElection; +import org.apache.helix.rest.metadatastore.constant.MetadataStoreRoutingConstants; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +public class ZkRoutingDataWriter implements MetadataStoreRoutingDataWriter { + private static final Logger LOG = LoggerFactory.getLogger(ZkBaseDataAccessor.class); + + private final String _namespace; + private final HelixZkClient _zkClient; + private final ZkDistributedLeaderElection _leaderElection; + + public ZkRoutingDataWriter(String namespace, String zkAddress) { + if (namespace == null || namespace.isEmpty()) { + throw new IllegalArgumentException("namespace cannot be null or empty!"); + } + _namespace = namespace; + if (zkAddress == null || zkAddress.isEmpty()) { + throw new IllegalArgumentException("Zk address cannot be null or empty!"); + } + _zkClient = DedicatedZkClientFactory.getInstance() + .buildZkClient(new HelixZkClient.ZkConnectionConfig(zkAddress), + new HelixZkClient.ZkClientConfig().setZkSerializer(new ZNRecordSerializer())); + + // Ensure that ROUTING_DATA_PATH exists in ZK. If not, create + // create() semantic will fail if it already exists + try { + _zkClient.createPersistent(MetadataStoreRoutingConstants.ROUTING_DATA_PATH); + } catch (ZkNodeExistsException e) { + // This is okay Review comment: MetadataStoreRoutingConstants.ROUTING_DATA_PATH is not a nested path and does not have a parent path. If ZkNodeExistsException occurs, that means the path exists already. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@helix.apache.org For additional commands, e-mail: reviews-h...@helix.apache.org
