hachikuji commented on code in PR #12862: URL: https://github.com/apache/kafka/pull/12862#discussion_r1035495650
########## clients/src/main/java/org/apache/kafka/clients/consumer/internals/NetworkClientDelegate.java: ########## @@ -0,0 +1,221 @@ +/* + * 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.clients.consumer.internals; + +import org.apache.kafka.clients.ClientRequest; +import org.apache.kafka.clients.ClientResponse; +import org.apache.kafka.clients.KafkaClient; +import org.apache.kafka.clients.RequestCompletionHandler; +import org.apache.kafka.common.Node; +import org.apache.kafka.common.errors.DisconnectException; +import org.apache.kafka.common.errors.TimeoutException; +import org.apache.kafka.common.errors.WakeupException; +import org.apache.kafka.common.requests.AbstractRequest; +import org.apache.kafka.common.utils.LogContext; +import org.apache.kafka.common.utils.Time; +import org.apache.kafka.common.utils.Timer; +import org.slf4j.Logger; + +import java.io.IOException; +import java.util.ArrayDeque; +import java.util.List; +import java.util.Objects; +import java.util.Optional; +import java.util.Queue; + +/** + * A wrapper around the {@link org.apache.kafka.clients.NetworkClient} to handle poll and send operations. + */ +public class NetworkClientDelegate implements AutoCloseable { + private final KafkaClient client; + private final Time time; + private final Logger log; + private boolean wakeup = false; + private final Queue<UnsentRequest> unsentRequests; + + public NetworkClientDelegate( + final Time time, + final LogContext logContext, + final KafkaClient client) { + this.time = time; + this.client = client; + this.log = logContext.logger(getClass()); + this.unsentRequests = new ArrayDeque<>(); + } + + public List<ClientResponse> poll(Timer timer, boolean disableWakeup) { + if (!disableWakeup) { + // trigger wakeups after checking for disconnects so that the callbacks will be ready + // to be fired on the next call to poll() + maybeTriggerWakeup(); + } + + trySend(); + return this.client.poll(timer.timeoutMs(), time.milliseconds()); + } + + private void trySend() { + while (unsentRequests.size() > 0) { + UnsentRequest unsent = unsentRequests.poll(); + if (unsent.timer.isExpired()) { + // TODO: expired request should be marked + unsent.callback.ifPresent(c -> c.onFailure(new TimeoutException( + "Failed to send request after " + unsent.timer.timeoutMs() + " " + "ms."))); + continue; + } + + doSend(unsent); + } + } + + static boolean isReady(KafkaClient client, Node node, long currentTime) { + client.poll(0, currentTime); + return client.isReady(node, currentTime); + } + + public void doSend(UnsentRequest r) { + long now = time.milliseconds(); + Node node = r.node.orElse(client.leastLoadedNode(now)); + ClientRequest request = makeClientRequest(r, node); + // TODO: Sounds like we need to check disconnections for each node and complete the request with + // authentication error + if (isReady(client, node, now)) { + client.send(request, now); + } + } + + private ClientRequest makeClientRequest(UnsentRequest unsent, Node node) { + return client.newClientRequest( + node.idString(), + unsent.abstractBuilder, + time.milliseconds(), + true, + (int) unsent.timer.remainingMs(), + unsent.callback.orElse(new RequestFutureCompletionHandlerBase())); + } + + public List<ClientResponse> poll() { + return this.poll(time.timer(0), false); + } + + public void maybeTriggerWakeup() { + if (this.wakeup) { + this.wakeup = false; + throw new WakeupException(); + } + } + + public void wakeup() { + this.wakeup = true; + this.client.wakeup(); + } + + public Node leastLoadedNode() { + return this.client.leastLoadedNode(time.milliseconds()); + } + + public void add(UnsentRequest r) { + unsentRequests.add(r); + } + + public void ready(Node node) { + client.ready(node, time.milliseconds()); + } + + /** + * Check if the code is disconnected and unavailable for immediate reconnection (i.e. if it is in + * reconnect backoff window following the disconnect). + */ + public boolean nodeUnavailable(Node node) { + return client.connectionFailed(node) && client.connectionDelay(node, time.milliseconds()) > 0; + } + + public void tryDisconnect(Optional<Node> coordinator) { + coordinator.ifPresent(node -> client.disconnect(node.idString())); + } + + public void close() throws IOException { + this.client.close(); + } + + public static class UnsentRequest { + private final Optional<RequestFutureCompletionHandlerBase> callback; + private final AbstractRequest.Builder abstractBuilder; + private final Optional<Node> node; // empty if random node can be choosen + private final Timer timer; + + public UnsentRequest(final Timer timer, + final AbstractRequest.Builder abstractBuilder, + final RequestFutureCompletionHandlerBase callback) { + this(timer, abstractBuilder, callback, null); + } + + public UnsentRequest(final Timer timer, + final AbstractRequest.Builder abstractBuilder, + final RequestFutureCompletionHandlerBase callback, + final Node node) { + Objects.requireNonNull(abstractBuilder); + this.abstractBuilder = abstractBuilder; + this.node = Optional.ofNullable(node); + this.callback = Optional.ofNullable(callback); + this.timer = timer; + } + } + + public static class RequestFutureCompletionHandlerBase implements RequestCompletionHandler { + private final RequestFuture<ClientResponse> future; + private ClientResponse response; + private RuntimeException e; + + RequestFutureCompletionHandlerBase() { + this.future = new RequestFuture<>(); + } + + public void fireCompletion() { + if (e != null) { + future.raise(e); + } else if (response.authenticationException() != null) { + future.raise(response.authenticationException()); + } else if (response.wasDisconnected()) { + //log.debug("Cancelled request with header {} due to node {} being disconnected", response + // .requestHeader(), response.destination()); + future.raise(DisconnectException.INSTANCE); + } else if (response.versionMismatch() != null) { + future.raise(response.versionMismatch()); + } else { + future.complete(response); + } + } + + public void onFailure(RuntimeException e) { + this.e = e; + fireCompletion(); + handleResponse(response, e); + } + + public void handleResponse(ClientResponse r, Throwable t) {} Review Comment: Why would we not need it for fetch requests? -- 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: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
