b02ee1106f
Motivation: Recently I'm going to build MQTT broker and client based on Netty. I had MQTT encoder and decoder founded, while no basic examples. So I'm going to share my simple heartBeat MQTT broker and client as an example. Modification: New MQTT heartBeat example under io.netty.example/mqtt/heartBeat/. Result: Client would send CONNECT and PINGREQ(heartBeat message). - CONNECT: once channel active - PINGREQ: once IdleStateEvent triggered, which is 20 seconds in this example Client would discard all messages it received. MQTT broker could handle CONNECT, PINGREQ and DISCONNECT messages. - CONNECT: send CONNACK back - PINGREQ: send PINGRESP back - DISCONNECT: close the channel Broker would close the channel if 2 heartBeat lost, which set to 45 seconds in this example.
65 lines
2.7 KiB
Java
65 lines
2.7 KiB
Java
/*
|
|
* Copyright 2019 The Netty Project
|
|
*
|
|
* The Netty Project 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 io.netty.example.mqtt.heartBeat;
|
|
|
|
import io.netty.bootstrap.Bootstrap;
|
|
import io.netty.channel.ChannelFuture;
|
|
import io.netty.channel.ChannelInitializer;
|
|
import io.netty.channel.EventLoopGroup;
|
|
import io.netty.channel.nio.NioEventLoopGroup;
|
|
import io.netty.channel.socket.SocketChannel;
|
|
import io.netty.channel.socket.nio.NioSocketChannel;
|
|
import io.netty.handler.codec.mqtt.MqttDecoder;
|
|
import io.netty.handler.codec.mqtt.MqttEncoder;
|
|
import io.netty.handler.timeout.IdleStateHandler;
|
|
|
|
import java.util.concurrent.TimeUnit;
|
|
|
|
public final class MqttHeartBeatClient {
|
|
private MqttHeartBeatClient() {
|
|
}
|
|
|
|
private static final String HOST = System.getProperty("host", "127.0.0.1");
|
|
private static final int PORT = Integer.parseInt(System.getProperty("port", "1883"));
|
|
private static final String CLIENT_ID = System.getProperty("clientId", "guestClient");
|
|
private static final String USER_NAME = System.getProperty("userName", "guest");
|
|
private static final String PASSWORD = System.getProperty("password", "guest");
|
|
|
|
public static void main(String[] args) throws Exception {
|
|
EventLoopGroup workerGroup = new NioEventLoopGroup();
|
|
|
|
try {
|
|
Bootstrap b = new Bootstrap();
|
|
b.group(workerGroup);
|
|
b.channel(NioSocketChannel.class);
|
|
b.handler(new ChannelInitializer<SocketChannel>() {
|
|
protected void initChannel(SocketChannel ch) throws Exception {
|
|
ch.pipeline().addLast("encoder", MqttEncoder.INSTANCE);
|
|
ch.pipeline().addLast("decoder", new MqttDecoder());
|
|
ch.pipeline().addLast("heartBeatHandler", new IdleStateHandler(0, 20, 0, TimeUnit.SECONDS));
|
|
ch.pipeline().addLast("handler", new MqttHeartBeatClientHandler(CLIENT_ID, USER_NAME, PASSWORD));
|
|
}
|
|
});
|
|
|
|
ChannelFuture f = b.connect(HOST, PORT).sync();
|
|
System.out.println("Client connected");
|
|
f.channel().closeFuture().sync();
|
|
} finally {
|
|
workerGroup.shutdownGracefully();
|
|
}
|
|
}
|
|
}
|