abbccdda commented on a change in pull request #9012: URL: https://github.com/apache/kafka/pull/9012#discussion_r457010788
########## File path: core/src/main/scala/kafka/server/BrokerToControllerChannelManager.scala ########## @@ -0,0 +1,211 @@ +/* + * 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 kafka.server + +import java.util.concurrent.{BlockingQueue, LinkedBlockingQueue, TimeUnit} + +import kafka.common.{InterBrokerSendThread, RequestAndCompletionHandler} +import kafka.network.RequestChannel +import kafka.utils.Logging +import org.apache.kafka.clients._ +import org.apache.kafka.common.requests.AbstractRequest +import org.apache.kafka.common.utils.{LogContext, Time} +import org.apache.kafka.common.Node +import org.apache.kafka.common.metrics.Metrics +import org.apache.kafka.common.network._ +import org.apache.kafka.common.protocol.Errors +import org.apache.kafka.common.requests.AbstractRequest.NoOpRequestBuilder +import org.apache.kafka.common.security.JaasContext + +import scala.collection.mutable +import scala.jdk.CollectionConverters._ + +/** + * This class manages the connection between a broker and the controller. It runs a single + * {@link BrokerToControllerRequestThread} which uses the broker's metadata cache as its own metadata to find + * and connect to the controller. The channel is async and runs the network connection in the background. + * The maximum number of in-flight requests are set to one to ensure orderly response from the controller, therefore + * care must be taken to not block on outstanding requests for too long. + */ +class BrokerToControllerChannelManager(metadataCache: kafka.server.MetadataCache, + time: Time, + metrics: Metrics, + config: KafkaConfig, + threadNamePrefix: Option[String] = None) extends Logging { + private val requestQueue = new LinkedBlockingQueue[BrokerToControllerQueueItem] + private val logContext = new LogContext(s"[broker-${config.brokerId}-to-controller] ") + private val manualMetadataUpdater = new ManualMetadataUpdater() + private val requestThread = newRequestThread + + def start(): Unit = { + requestThread.start() + } + + def shutdown(): Unit = { + requestThread.shutdown() + requestThread.awaitShutdown() + } + + private[server] def newRequestThread = { + val brokerToControllerListenerName = config.controlPlaneListenerName.getOrElse(config.interBrokerListenerName) + val brokerToControllerSecurityProtocol = config.controlPlaneSecurityProtocol.getOrElse(config.interBrokerSecurityProtocol) + + val networkClient = { + val channelBuilder = ChannelBuilders.clientChannelBuilder( + brokerToControllerSecurityProtocol, + JaasContext.Type.SERVER, + config, + brokerToControllerListenerName, + config.saslMechanismInterBrokerProtocol, + time, + config.saslInterBrokerHandshakeRequestEnable, + logContext + ) + val selector = new Selector( + NetworkReceive.UNLIMITED, + Selector.NO_IDLE_TIMEOUT_MS, + metrics, + time, + "BrokerToControllerChannel", + Map("BrokerId" -> config.brokerId.toString).asJava, + false, + channelBuilder, + logContext + ) + new NetworkClient( + selector, + manualMetadataUpdater, + config.brokerId.toString, + 1, + 0, + 0, + Selectable.USE_DEFAULT_BUFFER_SIZE, + Selectable.USE_DEFAULT_BUFFER_SIZE, + config.requestTimeoutMs, + config.connectionSetupTimeoutMs, + config.connectionSetupTimeoutMaxMs, + ClientDnsLookup.DEFAULT, + time, + false, + new ApiVersions, + logContext + ) + } + val threadName = threadNamePrefix match { + case None => s"broker-${config.brokerId}-to-controller-send-thread" + case Some(name) => s"$name:broker-${config.brokerId}-to-controller-send-thread" + } + + new BrokerToControllerRequestThread(networkClient, manualMetadataUpdater, requestQueue, metadataCache, config, + brokerToControllerListenerName, time, threadName) + } + + private[server] def sendRequest(request: RequestChannel.Request, + callback: RequestCompletionHandler): Unit = { + val requestBuilder = new NoOpRequestBuilder(request.context.header.apiKey, request.body[AbstractRequest]) + requestQueue.put(BrokerToControllerQueueItem(requestBuilder, callback, "")) + } + + private[server] def forwardRequest(originalRequest: RequestChannel.Request, + callback: RequestCompletionHandler): Unit = { + val requestBuilder = new NoOpRequestBuilder(originalRequest.context.header.apiKey, originalRequest.body[AbstractRequest]) + requestQueue.put(BrokerToControllerQueueItem(requestBuilder, callback, originalRequest.context.principal.getName)) + } +} + +case class BrokerToControllerQueueItem(request: AbstractRequest.Builder[_ <: AbstractRequest], + callback: RequestCompletionHandler, + initialPrincipalName: String) + +class BrokerToControllerRequestThread(networkClient: KafkaClient, + metadataUpdater: ManualMetadataUpdater, + requestQueue: BlockingQueue[BrokerToControllerQueueItem], + metadataCache: kafka.server.MetadataCache, + config: KafkaConfig, + listenerName: ListenerName, + time: Time, + threadName: String) + extends InterBrokerSendThread(threadName, networkClient, time, isInterruptible = false) { + + private var activeController: Option[Node] = None + + override def requestTimeoutMs: Int = config.controllerSocketTimeoutMs + + override def generateRequests(): Iterable[RequestAndCompletionHandler] = { + val requestsToSend = new mutable.Queue[RequestAndCompletionHandler] + if (requestQueue.peek() != null) { + val topRequest = requestQueue.take() + + val request = RequestAndCompletionHandler( + activeController.get, + topRequest.request, + handleResponse(topRequest), + topRequest.initialPrincipalName) + requestsToSend.enqueue(request) + } + requestsToSend + } + + private[server] def handleResponse(request: BrokerToControllerQueueItem)(response: ClientResponse): Unit = { + if (response.wasDisconnected()) { + activeController = None + requestQueue.put(request) + } else if (response.responseBody().errorCounts().containsKey(Errors.NOT_CONTROLLER)) { + // just close the controller connection and wait for metadata cache update in doWork + networkClient.close(activeController.get.idString) + activeController = None + requestQueue.put(request) + } else { + request.callback.onComplete(response) + } + } + + private[server] def backoff(): Unit = pause(100, TimeUnit.MILLISECONDS) Review comment: Will consider adding it after https://github.com/apache/kafka/pull/8421 lands ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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