| /* |
| * 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.druid.indexing.overlord.supervisor; |
| |
| import com.google.common.collect.ImmutableMap; |
| import org.apache.druid.indexing.overlord.DataSourceMetadata; |
| import org.apache.druid.indexing.overlord.supervisor.autoscaler.LagStats; |
| |
| import javax.annotation.Nullable; |
| import java.util.Map; |
| |
| public interface Supervisor |
| { |
| void start(); |
| |
| /** |
| * @param stopGracefully If true, supervisor will cleanly shutdown managed tasks if possible (for example signalling |
| * them to publish their segments and exit). The implementation may block until the tasks have |
| * either acknowledged or completed. If false, supervisor will stop immediately and leave any |
| * running tasks as they are. |
| */ |
| void stop(boolean stopGracefully); |
| |
| SupervisorReport getStatus(); |
| |
| SupervisorStateManager.State getState(); |
| |
| default Map<String, Map<String, Object>> getStats() |
| { |
| return ImmutableMap.of(); |
| } |
| |
| @Nullable |
| default Boolean isHealthy() |
| { |
| return null; // default implementation for interface compatability; returning null since true or false is misleading |
| } |
| |
| void reset(DataSourceMetadata dataSourceMetadata); |
| |
| /** |
| * The definition of checkpoint is not very strict as currently it does not affect data or control path. |
| * On this call Supervisor can potentially checkpoint data processed so far to some durable storage |
| * for example - Kafka/Kinesis Supervisor uses this to merge and handoff segments containing at least the data |
| * represented by {@param currentCheckpoint} DataSourceMetadata |
| * |
| * @param taskGroupId unique Identifier to figure out for which sequence to do checkpointing |
| * @param checkpointMetadata metadata for the sequence to currently checkpoint |
| */ |
| void checkpoint(int taskGroupId, DataSourceMetadata checkpointMetadata); |
| |
| /** |
| * Computes maxLag, totalLag and avgLag |
| */ |
| LagStats computeLagStats(); |
| |
| int getActiveTaskGroupsCount(); |
| } |