net.anyflow.lannister.packetreceiver.PublishReceiver.java Source code

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Here is the source code for net.anyflow.lannister.packetreceiver.PublishReceiver.java

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/*
 * Copyright 2016 The Lannister Project
 * 
 * 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 net.anyflow.lannister.packetreceiver;

import java.util.Date;

import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.mqtt.MqttPublishMessage;
import net.anyflow.lannister.AbnormalDisconnectEventArgs;
import net.anyflow.lannister.Statistics;
import net.anyflow.lannister.message.InboundMessageStatus;
import net.anyflow.lannister.message.Message;
import net.anyflow.lannister.message.MessageFactory;
import net.anyflow.lannister.plugin.DisconnectEventListener;
import net.anyflow.lannister.plugin.IMessage;
import net.anyflow.lannister.plugin.Plugins;
import net.anyflow.lannister.plugin.PublishEventArgs;
import net.anyflow.lannister.plugin.PublishEventListener;
import net.anyflow.lannister.session.Session;
import net.anyflow.lannister.topic.Topic;
import net.anyflow.lannister.topic.TopicMatcher;

public class PublishReceiver extends SimpleChannelInboundHandler<MqttPublishMessage> {

    private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(PublishReceiver.class);

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, MqttPublishMessage msg) throws Exception {
        logger.debug("packet incoming [message={}]", msg.toString());
        Statistics.SELF.add(Statistics.Criterion.MESSAGES_PUBLISH_RECEIVED, 1);

        Session session = Session.NEXUS.get(ctx.channel().id());
        if (session == null) {
            logger.error("None exist session message [message={}]", msg.toString());

            ctx.channel().disconnect().addListener(ChannelFutureListener.CLOSE).addListener(fs -> // [MQTT-4.8.0-1]
            Plugins.SELF.get(DisconnectEventListener.class).disconnected(new AbnormalDisconnectEventArgs()));
            return;
        }

        session.setLastIncomingTime(new Date());

        if (!TopicMatcher.isValid(msg.variableHeader().topicName(), false)) {
            session.dispose(true);
            return;
        }

        Message message = Message.newMessage(session.clientId(), msg);

        if (!Plugins.SELF.get(PublishEventListener.class).allowPublish(new PublishEventArgs() {
            @Override
            public IMessage message() {
                return message;
            }
        })) {
            session.dispose(true);
            return;
        }

        // TODO What to do when sender re-publish message corrensponds to
        // unacked status?

        // TODO Until it has received the corresponding PUBREL packet, the
        // Receiver MUST acknowledge any subsequent PUBLISH packet with the same
        // Packet Identifier by sending a PUBREC. It MUST NOT cause duplicate
        // messages to be delivered to any onward recipients in this
        // case.[MQTT-4.3.3-2].

        final Topic topic = Topic.NEXUS.publish(message);

        switch (msg.fixedHeader().qosLevel()) {
        case AT_MOST_ONCE:
            return; // QoS 0 do not send any acknowledge packet [MQTT-3.3.4-1]

        case AT_LEAST_ONCE:
            session.send(MessageFactory.puback(msg.variableHeader().messageId())).addListener(
                    f -> topic.removeInboundMessageStatus(session.clientId(), msg.variableHeader().messageId())); // [MQTT-3.3.4-1],[MQTT-2.3.1-6]
            logger.debug("Inbound message status REMOVED [clientId={}, messageId={}]", session.clientId(),
                    msg.variableHeader().messageId());
            return;

        case EXACTLY_ONCE:
            session.send(MessageFactory.pubrec(msg.variableHeader().messageId()))
                    .addListener(f -> topic.setInboundMessageStatus(session.clientId(),
                            msg.variableHeader().messageId(), InboundMessageStatus.Status.PUBRECED)); // [MQTT-3.3.4-1],[MQTT-2.3.1-6]
            return;

        default:
            session.dispose(true); // [MQTT-3.3.1-4]
            return;
        }
    }
}