mimaison commented on code in PR #21336: URL: https://github.com/apache/kafka/pull/21336#discussion_r2731223887
########## server/src/main/java/org/apache/kafka/server/BrokerLifecycleManager.java: ########## @@ -0,0 +1,725 @@ +/* + * 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.kafka.server; + +import org.apache.kafka.clients.ClientResponse; +import org.apache.kafka.common.Uuid; +import org.apache.kafka.common.message.BrokerHeartbeatRequestData; +import org.apache.kafka.common.message.BrokerHeartbeatResponseData; +import org.apache.kafka.common.message.BrokerRegistrationRequestData; +import org.apache.kafka.common.message.BrokerRegistrationRequestData.ListenerCollection; +import org.apache.kafka.common.protocol.Errors; +import org.apache.kafka.common.requests.BrokerHeartbeatRequest; +import org.apache.kafka.common.requests.BrokerHeartbeatResponse; +import org.apache.kafka.common.requests.BrokerRegistrationRequest; +import org.apache.kafka.common.requests.BrokerRegistrationResponse; +import org.apache.kafka.common.utils.LogContext; +import org.apache.kafka.common.utils.Time; +import org.apache.kafka.metadata.BrokerState; +import org.apache.kafka.metadata.VersionRange; +import org.apache.kafka.queue.EventQueue; +import org.apache.kafka.queue.KafkaEventQueue; +import org.apache.kafka.server.common.ControllerRequestCompletionHandler; +import org.apache.kafka.server.common.NodeToControllerChannelManager; +import org.apache.kafka.server.config.AbstractKafkaConfig; + +import org.slf4j.Logger; + +import java.util.ArrayList; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Optional; +import java.util.OptionalLong; +import java.util.Set; +import java.util.concurrent.CompletableFuture; +import java.util.function.Supplier; + +import static java.util.concurrent.TimeUnit.MILLISECONDS; +import static java.util.concurrent.TimeUnit.NANOSECONDS; + +/** + * The broker lifecycle manager owns the broker state. + * + * Its inputs are messages passed in from other parts of the broker and from the + * controller: requests to start up, or shut down, for example. Its output are the broker + * state and various futures that can be used to wait for broker state transitions to + * occur. + * + * The lifecycle manager handles registering the broker with the controller, as described + * in KIP-631. After registration is complete, it handles sending periodic broker + * heartbeats and processing the responses. + * + * This code uses an event queue paradigm. Modifications get translated into events, which + * are placed on the queue to be processed sequentially. As described in the JavaDoc for + * each variable, most mutable state can be accessed only from that event queue thread. + * In some cases we expose a volatile variable which can be read from any thread, but only + * written from the event queue thread. + */ +public class BrokerLifecycleManager { + + private final Logger logger; + private final KafkaEventQueue eventQueue; + private final AbstractKafkaConfig config; + private final Time time; + private final Set<Uuid> logDirs; + private final Runnable shutdownHook; + + /** + * The broker id. + */ + private final int nodeId; + + /** + * The broker rack, or null if there is no configured rack. + */ + private final Optional<String> rack; + + /** + * How long to wait for registration to succeed before failing the startup process. + */ + private final long initialTimeoutNs; + + /** + * The broker incarnation ID. This ID uniquely identifies each time we start the broker + */ + private final Uuid incarnationId = Uuid.randomUuid(); + + /** + * A future which is completed just as soon as the broker has caught up with the latest + * metadata offset for the first time. + */ + private final CompletableFuture<Void> initialCatchUpFuture = new CompletableFuture<>(); + + /** + * A future which is completed when the broker is unfenced for the first time. + */ + private final CompletableFuture<Void> initialUnfenceFuture = new CompletableFuture<>(); + + /** + * A future which is completed when controlled shutdown is done. + */ + private final CompletableFuture<Void> controlledShutdownFuture = new CompletableFuture<>(); + + /** + * The broker epoch, or -1 if the broker has not yet registered. This variable can only + * be written from the event queue thread. + */ + private volatile long brokerEpoch = -1L; + + /** + * The current broker state. This variable can only be written from the event queue + * thread. + */ + private volatile BrokerState state = BrokerState.NOT_RUNNING; + + /** + * A thread-safe callback function which gives this manager the current highest metadata + * offset. This variable can only be read or written from the event queue thread. + */ + private Supplier<Long> highestMetadataOffsetProvider; + + /** + * True only if we are ready to unfence the broker. This variable can only be read or + * written from the event queue thread. + */ + private boolean readyToUnfence = false; + + /** + * Map of accumulated offline directories. The value is true if the directory couldn't be communicated Review Comment: Fixed -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
