mcvsubbu commented on a change in pull request #4323: [Controller Separation] Add logic for lead controller resource URL: https://github.com/apache/incubator-pinot/pull/4323#discussion_r304153103
########## File path: pinot-controller/src/main/java/org/apache/pinot/controller/LeadControllerManager.java ########## @@ -0,0 +1,157 @@ +/** + * 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. + */ +package org.apache.pinot.controller; + +import java.util.Set; +import org.apache.helix.model.ExternalView; +import org.apache.pinot.common.config.TableNameBuilder; +import org.apache.pinot.common.utils.helix.HelixHelper; +import org.apache.pinot.controller.helix.core.PinotHelixResourceManager; +import org.apache.pinot.controller.helix.core.statemodel.LeadControllerChecker; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import static org.apache.pinot.common.utils.CommonConstants.Helix.LEAD_CONTROLLER_RESOURCE_NAME; +import static org.apache.pinot.common.utils.CommonConstants.Helix.NUMBER_OF_PARTITIONS_IN_LEAD_CONTROLLER_RESOURCE; + + +public class LeadControllerManager { + private static final Logger LOGGER = LoggerFactory.getLogger(LeadControllerManager.class); + + private final LeadControllerChecker _leadControllerChecker; + private PinotHelixResourceManager _pinotHelixResourceManager; + private boolean _amIHelixLeader = false; + + public LeadControllerManager() { + _leadControllerChecker = new LeadControllerChecker(); + } + + public void registerResourceManager(PinotHelixResourceManager pinotHelixResourceManager) { + _pinotHelixResourceManager = pinotHelixResourceManager; + } + + /** + * Check whether the current controller is the leader for the given table. Return true if current controller is the leader for this table. + * Otherwise check whether the current controller is helix leader. + * @param tableName table name with/without table type. + */ + public boolean isLeaderForTable(String tableName) { + String rawTableName = TableNameBuilder.extractRawTableName(tableName); + int partitionIndex = + HelixHelper.getPartitionIdForTable(rawTableName, NUMBER_OF_PARTITIONS_IN_LEAD_CONTROLLER_RESOURCE); + if (_leadControllerChecker.isPartitionLeader(partitionIndex)) { + return true; + } else { + return isHelixLeader(); + } + } + + /** + * Get lead controller id and partition index for given table. Returns -1 as partition index and null as lead controller id if not found. + * @param tableName table name with/without table type. + * @return lead controller id and partition index + */ + public LeadControllerResponse getLeadControllerAndPartitionIdForTable(String tableName) { + String rawTableName = TableNameBuilder.extractRawTableName(tableName); + ExternalView leadControllerResourceExternalView = _pinotHelixResourceManager.getHelixAdmin() + .getResourceExternalView(_pinotHelixResourceManager.getHelixClusterName(), LEAD_CONTROLLER_RESOURCE_NAME); + if (leadControllerResourceExternalView == null) { + return new LeadControllerResponse(); + } + Set<String> partitionSet = leadControllerResourceExternalView.getPartitionSet(); + if (partitionSet == null || partitionSet.isEmpty()) { + return new LeadControllerResponse(); + } + + int numPartitions = partitionSet.size(); + int partitionIndex = HelixHelper.getPartitionIdForTable(rawTableName, numPartitions); + String leadControllerId = HelixHelper.getLeadControllerForTable(leadControllerResourceExternalView, rawTableName); + return new LeadControllerResponse(partitionIndex, leadControllerId); + } + + public synchronized void addPartitionLeader(String partitionName) { + _leadControllerChecker.addPartitionLeader(partitionName); + } + + public synchronized void removePartitionLeader(String partitionName) { + _leadControllerChecker.removePartitionLeader(partitionName); + } + + /** + * Checks if the current controller host is Helix leader. + */ + private boolean isHelixLeader() { + return _amIHelixLeader; + } + + /** + * Response class to return lead controller id and partition index. + */ + public class LeadControllerResponse { + private int _partitionIndex; + private String _leadControllerId; + + public LeadControllerResponse(int partitionIndex, String leadControllerId) { + _partitionIndex = partitionIndex; + _leadControllerId = leadControllerId; + } + + public LeadControllerResponse() { + _partitionIndex = -1; + _leadControllerId = null; + } + + public int getPartitionIndex() { + return _partitionIndex; + } + + public String getLeadControllerId() { + return _leadControllerId; + } + + @Override + public String toString() { + return "Partition index: " + getPartitionIndex() + ", lead controller id: " + getLeadControllerId(); + } + } + + /** + * Callback on changes in the controller. Should be registered to the controller callback. Review comment: can you elaborate this comment? This callback will only be triggered if the controller is in dual mode, right? It won't be triggered in any other mode. ---------------------------------------------------------------- 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: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
