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HiveMQ MQTT Client is an MQTT 5.0 and MQTT 3.1.1 compatible and feature-rich high-performance Java client library with different API flavours and backpressure support
/*
* Copyright 2018-present HiveMQ and the HiveMQ Community
*
* Licensed 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 com.hivemq.client.internal.mqtt.handler.publish.outgoing;
import com.hivemq.client.internal.annotations.CallByThread;
import com.hivemq.client.internal.logging.InternalLogger;
import com.hivemq.client.internal.logging.InternalLoggerFactory;
import com.hivemq.client.internal.mqtt.MqttClientConfig;
import com.hivemq.client.internal.mqtt.MqttClientConnectionConfig;
import com.hivemq.client.internal.mqtt.advanced.interceptor.MqttClientInterceptors;
import com.hivemq.client.internal.mqtt.exceptions.MqttClientStateExceptions;
import com.hivemq.client.internal.mqtt.handler.MqttSessionAwareHandler;
import com.hivemq.client.internal.mqtt.handler.disconnect.MqttDisconnectUtil;
import com.hivemq.client.internal.mqtt.handler.publish.outgoing.MqttPubRelWithFlow.MqttQos2CompleteWithFlow;
import com.hivemq.client.internal.mqtt.handler.publish.outgoing.MqttPubRelWithFlow.MqttQos2IntermediateWithFlow;
import com.hivemq.client.internal.mqtt.handler.subscribe.MqttSubscriptionHandler;
import com.hivemq.client.internal.mqtt.ioc.ClientScope;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublish;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublishResult;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublishResult.MqttQos1Result;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublishResult.MqttQos2CompleteResult;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublishResult.MqttQos2IntermediateResult;
import com.hivemq.client.internal.mqtt.message.publish.MqttPublishResult.MqttQos2Result;
import com.hivemq.client.internal.mqtt.message.publish.MqttStatefulPublish;
import com.hivemq.client.internal.mqtt.message.publish.puback.MqttPubAck;
import com.hivemq.client.internal.mqtt.message.publish.pubcomp.MqttPubComp;
import com.hivemq.client.internal.mqtt.message.publish.pubrec.MqttPubRec;
import com.hivemq.client.internal.mqtt.message.publish.pubrel.MqttPubRel;
import com.hivemq.client.internal.mqtt.message.publish.pubrel.MqttPubRelBuilder;
import com.hivemq.client.internal.netty.ContextFuture;
import com.hivemq.client.internal.netty.DefaultContextPromise;
import com.hivemq.client.internal.util.Ranges;
import com.hivemq.client.internal.util.UnsignedDataTypes;
import com.hivemq.client.internal.util.collections.IntIndex;
import com.hivemq.client.internal.util.collections.NodeList;
import com.hivemq.client.mqtt.MqttClientState;
import com.hivemq.client.mqtt.datatypes.MqttQos;
import com.hivemq.client.mqtt.exceptions.ConnectionClosedException;
import com.hivemq.client.mqtt.mqtt5.advanced.interceptor.qos1.Mqtt5OutgoingQos1Interceptor;
import com.hivemq.client.mqtt.mqtt5.advanced.interceptor.qos2.Mqtt5OutgoingQos2Interceptor;
import com.hivemq.client.mqtt.mqtt5.exceptions.Mqtt5PubAckException;
import com.hivemq.client.mqtt.mqtt5.exceptions.Mqtt5PubRecException;
import com.hivemq.client.mqtt.mqtt5.message.disconnect.Mqtt5DisconnectReasonCode;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.EventLoop;
import io.reactivex.Flowable;
import io.reactivex.FlowableSubscriber;
import org.jctools.queues.SpscUnboundedArrayQueue;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.reactivestreams.Subscription;
import javax.inject.Inject;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicInteger;
import static com.hivemq.client.internal.mqtt.message.publish.MqttStatefulPublish.NO_PACKET_IDENTIFIER_QOS_0;
/**
* @author Silvio Giebl
*/
@ClientScope
public class MqttOutgoingQosHandler extends MqttSessionAwareHandler
implements FlowableSubscriber, Runnable, ContextFuture.Listener {
public static final @NotNull String NAME = "qos.outgoing";
private static final @NotNull InternalLogger LOGGER = InternalLoggerFactory.getLogger(MqttOutgoingQosHandler.class);
private static final IntIndex.@NotNull Spec INDEX_SPEC =
new IntIndex.Spec<>(x -> x.packetIdentifier);
private static final int MAX_CONCURRENT_PUBLISH_FLOWABLES = 64; // TODO configurable
private static final boolean QOS_2_COMPLETE_RESULT = false; // TODO configurable
private final @NotNull MqttClientConfig clientConfig;
private final @NotNull MqttPublishFlowables publishFlowables;
// valid for session
private final @NotNull SpscUnboundedArrayQueue queue = new SpscUnboundedArrayQueue<>(32);
private final @NotNull AtomicInteger queuedCounter = new AtomicInteger();
private final @NotNull NodeList pending = new NodeList<>();
private final @NotNull Ranges packetIdentifiers = new Ranges(1, 0);
// valid for connection
private final @NotNull IntIndex pendingIndex = new IntIndex<>(INDEX_SPEC);
private @Nullable MqttPubOrRelWithFlow resendPending;
private @Nullable MqttPublishWithFlow currentPending;
private int sendMaximum;
private @Nullable MqttTopicAliasMapping topicAliasMapping;
private @Nullable Subscription subscription;
private int shrinkRequests;
@Inject
MqttOutgoingQosHandler(final @NotNull MqttClientConfig clientConfig) {
this.clientConfig = clientConfig;
publishFlowables = new MqttPublishFlowables();
}
@Override
public void onSessionStartOrResume(
final @NotNull MqttClientConnectionConfig connectionConfig, final @NotNull EventLoop eventLoop) {
final int oldSendMaximum = sendMaximum;
final int newSendMaximum = Math.min(connectionConfig.getSendMaximum(),
UnsignedDataTypes.UNSIGNED_SHORT_MAX_VALUE - MqttSubscriptionHandler.MAX_SUB_PENDING);
sendMaximum = newSendMaximum;
packetIdentifiers.resize(newSendMaximum);
if (oldSendMaximum == 0) {
publishFlowables.flatMap(
f -> f, true, MAX_CONCURRENT_PUBLISH_FLOWABLES, Math.min(newSendMaximum, Flowable.bufferSize()))
.subscribe(this);
assert subscription != null;
subscription.request(newSendMaximum);
} else {
assert subscription != null;
final int newRequests = newSendMaximum - oldSendMaximum - shrinkRequests;
if (newRequests > 0) {
shrinkRequests = 0;
subscription.request(newRequests);
} else {
shrinkRequests = -newRequests;
}
}
topicAliasMapping = connectionConfig.getSendTopicAliasMapping();
pendingIndex.clear();
resendPending = pending.getFirst();
if ((resendPending != null) || (queuedCounter.get() > 0)) {
eventLoop.execute(this);
}
super.onSessionStartOrResume(connectionConfig, eventLoop);
}
@Override
public void onSubscribe(final @NotNull Subscription subscription) {
this.subscription = subscription;
}
@Override
public void onNext(final @NotNull MqttPublishWithFlow publishWithFlow) {
queue.offer(publishWithFlow);
if (queuedCounter.getAndIncrement() == 0) {
publishWithFlow.getAckFlow().getEventLoop().execute(this);
}
}
@Override
public void onComplete() {
LOGGER.error("MqttPublishFlowables is global and must never complete. This must not happen and is a bug.");
}
@Override
public void onError(final @NotNull Throwable t) {
LOGGER.error("MqttPublishFlowables is global and must never error. This must not happen and is a bug.", t);
}
@CallByThread("Netty EventLoop")
void request(final long n) {
assert subscription != null;
final int shrinkRequests = this.shrinkRequests;
if (shrinkRequests == 0) {
subscription.request(n);
} else if (n > shrinkRequests) {
this.shrinkRequests = 0;
subscription.request(n - shrinkRequests);
} else {
this.shrinkRequests -= n;
}
}
@CallByThread("Netty EventLoop")
@Override
public void run() {
if (!hasSession) {
if (!isRepublishIfSessionExpired()) {
clearQueued(MqttClientStateExceptions.notConnected());
}
return;
}
final ChannelHandlerContext ctx = this.ctx;
if (ctx == null) {
return;
}
final Channel channel = ctx.channel();
final int maxWrites = sendMaximum - pendingIndex.size();
int written = 0;
for (MqttPubOrRelWithFlow pubOrRelWithFlow = resendPending;
(pubOrRelWithFlow != null) && (written < maxWrites) && channel.isWritable();
resendPending = pubOrRelWithFlow = pubOrRelWithFlow.getNext()) {
resend(ctx, pubOrRelWithFlow);
written++;
}
int dequeued = 0;
while ((written < maxWrites) && channel.isWritable()) {
final MqttPublishWithFlow publishWithFlow = queue.poll();
if (publishWithFlow == null) {
break;
}
writePublish(ctx, publishWithFlow);
written++;
dequeued++;
}
if (written > 0) {
final boolean wasWritable = channel.isWritable();
ctx.flush();
if ((dequeued > 0) && (queuedCounter.addAndGet(-dequeued) > 0) && wasWritable) {
channel.eventLoop().execute(this);
}
}
}
@Override
public void channelWritabilityChanged(final @NotNull ChannelHandlerContext ctx) {
final Channel channel = ctx.channel();
if (channel.isWritable()) {
channel.eventLoop().execute(this);
}
ctx.fireChannelWritabilityChanged();
}
private void resend(
final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubOrRelWithFlow pubOrRelWithFlow) {
pendingIndex.put(pubOrRelWithFlow);
if (pubOrRelWithFlow instanceof MqttPublishWithFlow) {
final MqttPublishWithFlow publishWithFlow = (MqttPublishWithFlow) pubOrRelWithFlow;
final MqttStatefulPublish publish = publishWithFlow.getPublish()
.createStateful(publishWithFlow.packetIdentifier, true, topicAliasMapping);
writeQos1Or2Publish(ctx, publish, publishWithFlow);
} else {
final MqttPubRelWithFlow pubRelWithFlow = (MqttPubRelWithFlow) pubOrRelWithFlow;
writePubRel(ctx, pubRelWithFlow.getPubRel());
}
}
private void writePublish(
final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPublishWithFlow publishWithFlow) {
if (publishWithFlow.getPublish().getQos() == MqttQos.AT_MOST_ONCE) {
writeQos0Publish(ctx, publishWithFlow);
} else {
writeQos1Or2Publish(ctx, publishWithFlow);
}
}
private void writeQos0Publish(
final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPublishWithFlow publishWithFlow) {
ctx.write(publishWithFlow.getPublish().createStateful(NO_PACKET_IDENTIFIER_QOS_0, false, topicAliasMapping),
new DefaultContextPromise<>(ctx.channel(), publishWithFlow)).addListener(this);
}
@Override
public void operationComplete(final @NotNull ContextFuture future) {
final MqttPublishWithFlow publishWithFlow = future.getContext();
final MqttPublish publish = publishWithFlow.getPublish();
final MqttAckFlow ackFlow = publishWithFlow.getAckFlow();
final Throwable cause = future.cause();
if (!(cause instanceof IOException)) {
ackFlow.onNext(new MqttPublishResult(publish, cause));
} else {
ackFlow.onNext(new MqttPublishResult(publish, new ConnectionClosedException(cause)));
future.channel().pipeline().fireExceptionCaught(cause);
}
}
private void writeQos1Or2Publish(
final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPublishWithFlow publishWithFlow) {
final int packetIdentifier = packetIdentifiers.getId();
if (packetIdentifier < 0) {
LOGGER.error("No Packet Identifier available for QoS 1 or 2 PUBLISH. This must not happen and is a bug.");
return;
}
publishWithFlow.packetIdentifier = packetIdentifier;
pendingIndex.put(publishWithFlow);
pending.add(publishWithFlow);
writeQos1Or2Publish(ctx,
publishWithFlow.getPublish().createStateful(packetIdentifier, false, topicAliasMapping),
publishWithFlow);
}
private void writeQos1Or2Publish(
final @NotNull ChannelHandlerContext ctx,
final @NotNull MqttStatefulPublish publish,
final @NotNull MqttPublishWithFlow publishWithFlow) {
currentPending = publishWithFlow;
ctx.write(publish, ctx.voidPromise());
currentPending = null;
}
@Override
public void channelRead(final @NotNull ChannelHandlerContext ctx, final @NotNull Object msg) {
if (msg instanceof MqttPubAck) {
readPubAck(ctx, (MqttPubAck) msg);
} else if (msg instanceof MqttPubRec) {
readPubRec(ctx, (MqttPubRec) msg);
} else if (msg instanceof MqttPubComp) {
readPubComp(ctx, (MqttPubComp) msg);
} else {
ctx.fireChannelRead(msg);
}
}
private void readPubAck(final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubAck pubAck) {
final int packetIdentifier = pubAck.getPacketIdentifier();
final MqttPubOrRelWithFlow removed = pendingIndex.remove(packetIdentifier);
if (removed == null) {
error(ctx, "PUBACK contained unknown packet identifier");
return;
}
if (!(removed instanceof MqttPublishWithFlow)) { // MqttPubRelWithFlow
pendingIndex.put(removed); // revert
error(ctx, "PUBACK must not be received for a PUBREL");
return;
}
final MqttPublishWithFlow publishWithFlow = (MqttPublishWithFlow) removed;
final MqttPublish publish = publishWithFlow.getPublish();
if (publish.getQos() != MqttQos.AT_LEAST_ONCE) { // EXACTLY_ONCE
pendingIndex.put(removed); // revert
error(ctx, "PUBACK must not be received for a QoS 2 PUBLISH");
return;
}
completePending(ctx, publishWithFlow);
onPubAck(publish, pubAck);
final Throwable t = (pubAck.getReasonCode().isError()) ?
new Mqtt5PubAckException(pubAck, "PUBACK contained an Error Code") : null;
publishWithFlow.getAckFlow().onNext(new MqttQos1Result(publish, t, pubAck));
}
private void readPubRec(final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubRec pubRec) {
final int packetIdentifier = pubRec.getPacketIdentifier();
final MqttPubOrRelWithFlow got = pendingIndex.get(packetIdentifier);
if (got == null) {
error(ctx, "PUBREC contained unknown packet identifier");
return;
}
if (!(got instanceof MqttPublishWithFlow)) { // MqttPubRelWithFlow
error(ctx, "PUBREC must not be received when the PUBREL has already been sent");
return;
}
final MqttPublishWithFlow publishWithFlow = (MqttPublishWithFlow) got;
final MqttPublish publish = publishWithFlow.getPublish();
if (publish.getQos() != MqttQos.EXACTLY_ONCE) { // AT_LEAST_ONCE
error(ctx, "PUBREC must not be received for a QoS 1 PUBLISH");
return;
}
final MqttAckFlow ackFlow = publishWithFlow.getAckFlow();
if (pubRec.getReasonCode().isError()) {
pendingIndex.remove(packetIdentifier);
completePending(ctx, publishWithFlow);
onPubRecError(publish, pubRec);
final Throwable t = new Mqtt5PubRecException(pubRec, "PUBREC contained an Error Code");
ackFlow.onNext(new MqttQos2Result(publish, t, pubRec));
} else {
final MqttPubRel pubRel = buildPubRel(publish, pubRec);
if (QOS_2_COMPLETE_RESULT) {
replacePending(publishWithFlow, new MqttQos2CompleteWithFlow(publish, pubRec, pubRel, ackFlow));
} else {
final MqttQos2IntermediateWithFlow pubRelWithFlow = new MqttQos2IntermediateWithFlow(pubRel, ackFlow);
replacePending(publishWithFlow, pubRelWithFlow);
ackFlow.onNext(new MqttQos2IntermediateResult(publish, pubRec, pubRelWithFlow));
}
writePubRel(ctx, pubRel);
ctx.flush();
}
}
private void writePubRel(final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubRel pubRel) {
ctx.write(pubRel, ctx.voidPromise());
}
private void replacePending(
final @NotNull MqttPublishWithFlow publishWithFlow, final @NotNull MqttPubRelWithFlow pubRelWithFlow) {
pubRelWithFlow.packetIdentifier = publishWithFlow.packetIdentifier;
pendingIndex.put(pubRelWithFlow);
pending.replace(publishWithFlow, pubRelWithFlow);
}
private void readPubComp(final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubComp pubComp) {
final int packetIdentifier = pubComp.getPacketIdentifier();
final MqttPubOrRelWithFlow removed = pendingIndex.remove(packetIdentifier);
if (removed == null) {
error(ctx, "PUBCOMP contained unknown packet identifier");
return;
}
if (!(removed instanceof MqttPubRelWithFlow)) { // MqttPublishWithFlow
pendingIndex.put(removed); // revert
final MqttPublishWithFlow publishWithFlow = (MqttPublishWithFlow) removed;
if (publishWithFlow.getPublish().getQos() == MqttQos.AT_LEAST_ONCE) {
error(ctx, "PUBCOMP must not be received for a QoS 1 PUBLISH");
} else { // EXACTLY_ONCE
error(ctx, "PUBCOMP must not be received when the PUBREL has not been sent yet");
}
return;
}
final MqttPubRelWithFlow pubRelWithFlow = (MqttPubRelWithFlow) removed;
final MqttPubRel pubRel = pubRelWithFlow.getPubRel();
final MqttAckFlow ackFlow = pubRelWithFlow.getAckFlow();
completePending(ctx, pubRelWithFlow);
onPubComp(pubRel, pubComp);
if (QOS_2_COMPLETE_RESULT) {
final MqttQos2CompleteWithFlow complete = (MqttQos2CompleteWithFlow) pubRelWithFlow;
ackFlow.onNext(new MqttQos2CompleteResult(complete.getPublish(), complete.getPubRec(), pubRel, pubComp));
} else {
final MqttQos2IntermediateWithFlow intermediate = (MqttQos2IntermediateWithFlow) pubRelWithFlow;
if (intermediate.getAsBoolean()) {
ackFlow.acknowledged(1);
}
}
}
private void completePending(
final @NotNull ChannelHandlerContext ctx, final @NotNull MqttPubOrRelWithFlow oldPending) {
pending.remove(oldPending);
final int packetIdentifier = oldPending.packetIdentifier;
packetIdentifiers.returnId(packetIdentifier);
if (packetIdentifier > sendMaximum) {
packetIdentifiers.resize(sendMaximum);
}
if (resendPending != null) {
ctx.channel().eventLoop().execute(this);
}
}
@Override
public void exceptionCaught(final @NotNull ChannelHandlerContext ctx, final @NotNull Throwable cause) {
if (!(cause instanceof IOException) && (currentPending != null)) {
pendingIndex.remove(currentPending.packetIdentifier);
currentPending.getAckFlow().onNext(new MqttPublishResult(currentPending.getPublish(), cause));
completePending(ctx, currentPending);
currentPending = null;
} else {
ctx.fireExceptionCaught(cause);
}
}
@Override
public void onSessionEnd(final @NotNull Throwable cause) {
super.onSessionEnd(cause);
pendingIndex.clear();
resendPending = null;
if (isRepublishIfSessionExpired()) {
return;
}
for (MqttPubOrRelWithFlow current = pending.getFirst(); current != null; current = current.getNext()) {
packetIdentifiers.returnId(current.packetIdentifier);
if (current instanceof MqttPublishWithFlow) {
final MqttPublishWithFlow publishWithFlow = (MqttPublishWithFlow) current;
current.getAckFlow().onNext(new MqttPublishResult(publishWithFlow.getPublish(), cause));
} else if (QOS_2_COMPLETE_RESULT) {
final MqttQos2CompleteWithFlow complete = (MqttQos2CompleteWithFlow) current;
current.getAckFlow().onNext(new MqttQos2Result(complete.getPublish(), cause, complete.getPubRec()));
// TODO actually not an error, default PubComp?
} else {
final MqttQos2IntermediateWithFlow intermediate = (MqttQos2IntermediateWithFlow) current;
if (intermediate.getAsBoolean()) {
intermediate.getAckFlow().acknowledged(1);
}
}
}
pending.clear();
clearQueued(cause);
}
private boolean isRepublishIfSessionExpired() {
return clientConfig.isRepublishIfSessionExpired() && (clientConfig.getState() != MqttClientState.DISCONNECTED);
}
private void clearQueued(final @NotNull Throwable cause) {
int polled = 0;
while (true) {
final MqttPublishWithFlow publishWithFlow = queue.poll();
if (publishWithFlow == null) {
if (queuedCounter.addAndGet(-polled) == 0) {
break;
} else {
polled = 0;
continue;
}
}
publishWithFlow.getAckFlow().onNext(new MqttPublishResult(publishWithFlow.getPublish(), cause));
polled++;
}
}
private static void error(final @NotNull ChannelHandlerContext ctx, final @NotNull String reasonString) {
MqttDisconnectUtil.disconnect(ctx.channel(), Mqtt5DisconnectReasonCode.PROTOCOL_ERROR, reasonString);
}
private void onPubAck(final @NotNull MqttPublish publish, final @NotNull MqttPubAck pubAck) {
final MqttClientInterceptors interceptors = clientConfig.getAdvancedConfig().getInterceptors();
if (interceptors != null) {
final Mqtt5OutgoingQos1Interceptor interceptor = interceptors.getOutgoingQos1Interceptor();
if (interceptor != null) {
interceptor.onPubAck(clientConfig, publish, pubAck);
}
}
}
private void onPubRecError(final @NotNull MqttPublish publish, final @NotNull MqttPubRec pubRec) {
final MqttClientInterceptors interceptors = clientConfig.getAdvancedConfig().getInterceptors();
if (interceptors != null) {
final Mqtt5OutgoingQos2Interceptor interceptor = interceptors.getOutgoingQos2Interceptor();
if (interceptor != null) {
interceptor.onPubRecError(clientConfig, publish, pubRec);
}
}
}
private @NotNull MqttPubRel buildPubRel(final @NotNull MqttPublish publish, final @NotNull MqttPubRec pubRec) {
final MqttPubRelBuilder pubRelBuilder = new MqttPubRelBuilder(pubRec);
final MqttClientInterceptors interceptors = clientConfig.getAdvancedConfig().getInterceptors();
if (interceptors != null) {
final Mqtt5OutgoingQos2Interceptor interceptor = interceptors.getOutgoingQos2Interceptor();
if (interceptor != null) {
interceptor.onPubRec(clientConfig, publish, pubRec, pubRelBuilder);
}
}
return pubRelBuilder.build();
}
private void onPubComp(final @NotNull MqttPubRel pubRel, final @NotNull MqttPubComp pubComp) {
final MqttClientInterceptors interceptors = clientConfig.getAdvancedConfig().getInterceptors();
if (interceptors != null) {
final Mqtt5OutgoingQos2Interceptor interceptor = interceptors.getOutgoingQos2Interceptor();
if (interceptor != null) {
interceptor.onPubComp(clientConfig, pubRel, pubComp);
}
}
}
@NotNull MqttPublishFlowables getPublishFlowables() {
return publishFlowables;
}
}