spring boot整合netty

spring boot整合netty

之前花了几天去研究怎么使用netty做一个网关服务器，虽然最后还是没能用上我做的网关，但是呢netty是会用了，总结一下netty和spring boot整合。感觉不用spring boot都不会写代码了。哈哈哈

1. 在pom文件中添加相关的依赖，这里主要的就是netty的依赖，spring boot的相关依赖本文不提

        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
            <version>4.1.19.Final</version>
        </dependency>
        
         <dependency>
            <groupId>SpringBoot-Netty</groupId>
            <artifactId>SpringBoot-Netty</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

2. 在application.yml文件中配置

#不能用localhost,否则启动报异常:Unresolved address
#tcp监听的端口
tcp:
  port: 8090
# bossGroup的线程数
boss:
  thread:
    count: 2
# worker的线程数
worker:
  thread:
    count: 2
#是否使用长连接
so:
  keepalive:  true
  backlog: 100

3.编写NettyConfig netty的配置。

package com.advsun.netty.config;

import com.advsun.netty.handlers.StringProtocolInitalizer;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelOption;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;

import java.net.InetSocketAddress;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * @author 杨红星
 * @version 1.0.0
 */
@Configuration
public class NettyConfig {
    
    //读取yml中配置 
    @Value("${boss.thread.count}")
    private int bossCount;

    @Value("${worker.thread.count}")
    private int workerCount;

    @Value("${tcp.port}")
    private int tcpPort;

    @Value("${so.keepalive}")
    private boolean keepAlive;

    @Value("${so.backlog}")
    private int backlog;

    @Autowired
    @Qualifier("springProtocolInitializer")
    private StringProtocolInitalizer protocolInitalizer;
//bootstrap配置
    @SuppressWarnings("unchecked")
    @Bean(name = "serverBootstrap")
    public ServerBootstrap bootstrap() {
        ServerBootstrap b = new ServerBootstrap();
        b.group(bossGroup(), workerGroup())
                .channel(NioServerSocketChannel.class)
                .childHandler(protocolInitalizer);
        Map<ChannelOption<?>, Object> tcpChannelOptions = tcpChannelOptions();
        Set<ChannelOption<?>> keySet = tcpChannelOptions.keySet();
        for (@SuppressWarnings("rawtypes")
                ChannelOption option : keySet) {
            b.option(option, tcpChannelOptions.get(option));
        }
        return b;
    }

    @Bean(name = "bossGroup", destroyMethod = "shutdownGracefully")
    public NioEventLoopGroup bossGroup() {
        return new NioEventLoopGroup(bossCount);
    }

    @Bean(name = "workerGroup", destroyMethod = "shutdownGracefully")
    public NioEventLoopGroup workerGroup() {
        return new NioEventLoopGroup(workerCount);
    }

    @Bean(name = "tcpSocketAddress")
    public InetSocketAddress tcpPort() {
        return new InetSocketAddress(tcpPort);
    }

    @Bean(name = "tcpChannelOptions")
    public Map<ChannelOption<?>, Object> tcpChannelOptions() {
        Map<ChannelOption<?>, Object> options = new HashMap<ChannelOption<?>, Object>();
        options.put(ChannelOption.SO_KEEPALIVE, keepAlive);
        options.put(ChannelOption.SO_BACKLOG, backlog);
        return options;
    }

    @Bean(name = "stringEncoder")
    public StringEncoder stringEncoder() {
        return new StringEncoder();
    }

    @Bean(name = "stringDecoder")
    public StringDecoder stringDecoder() {
        return new StringDecoder();
    }

    /**
     * Necessary to make the Value annotations work.
     *
     * @return
     */
    @Bean
    public static PropertySourcesPlaceholderConfigurer propertyPlaceholderConfigurer() {
        return new PropertySourcesPlaceholderConfigurer();
    }
}

4.初始化的相关配置

package com.advsun.netty.handlers;

import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Component;

/**
 * @author 杨红星
 * @version 1.0.0
 */
@Component
@Qualifier("springProtocolInitializer")
public class StringProtocolInitalizer extends ChannelInitializer<SocketChannel> {

    @Autowired
    StringDecoder stringDecoder;

    @Autowired
    StringEncoder stringEncoder;

    @Autowired
    ServerHandler serverHandler;

    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        ChannelPipeline pipeline = ch.pipeline();
        pipeline.addLast("decoder", stringDecoder);
        pipeline.addLast("handler", serverHandler);
        pipeline.addLast("encoder", stringEncoder);
    }

    public StringDecoder getStringDecoder() {
        return stringDecoder;
    }

    public void setStringDecoder(StringDecoder stringDecoder) {
        this.stringDecoder = stringDecoder;
    }

    public StringEncoder getStringEncoder() {
        return stringEncoder;
    }

    public void setStringEncoder(StringEncoder stringEncoder) {
        this.stringEncoder = stringEncoder;
    }

    public ServerHandler getServerHandler() {
        return serverHandler;
    }

    public void setServerHandler(ServerHandler serverHandler) {
        this.serverHandler = serverHandler;
    }

}

5.tcp服务的配置

package com.advsun.netty.config;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Component;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import java.net.InetSocketAddress;

/**
 * @author 杨红星
 * @version 1.0.0
 */
@Component
public class TCPServer {
    @Autowired
    @Qualifier("serverBootstrap")
    private ServerBootstrap b;

    @Autowired
    @Qualifier("tcpSocketAddress")
    private InetSocketAddress tcpPort;

    private ChannelFuture serverChannelFuture;

    @PostConstruct
    public void start() throws Exception {
        System.out.println("Starting server at " + tcpPort);
        serverChannelFuture = b.bind(tcpPort).sync();
    }

    @PreDestroy
    public void stop() throws Exception {
        serverChannelFuture.channel().closeFuture().sync();
    }

    public ServerBootstrap getB() {
        return b;
    }

    public void setB(ServerBootstrap b) {
        this.b = b;
    }

    public InetSocketAddress getTcpPort() {
        return tcpPort;
    }

    public void setTcpPort(InetSocketAddress tcpPort) {
        this.tcpPort = tcpPort;
    }
}

6.serverHandler配置这里是实现业务逻辑的地方

package com.advsun.netty.handlers;

import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Component;

import java.net.InetAddress;

/**
 * @author 杨红星
 * @version 1.0.0
 */
@Component
@Qualifier("serverHandler")
@ChannelHandler.Sharable
public class ServerHandler extends SimpleChannelInboundHandler<String> {
    private static final Logger log = LoggerFactory.getLogger(ServerHandler.class);

    @Override
    public void channelRead0(ChannelHandlerContext ctx, String msg)
            throws Exception {
        log.info("client msg:"+msg);
        String clientIdToLong= ctx.channel().id().asLongText();
        log.info("client long id:"+clientIdToLong);
        String clientIdToShort= ctx.channel().id().asShortText();
        log.info("client short id:"+clientIdToShort);
        if(msg.indexOf("bye")!=-1){
            //close
            ctx.channel().close();
        }else{
            //send to client
            ctx.channel().writeAndFlush("Yoru msg is:"+msg);

        }

    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {

        log.info("RamoteAddress : " + ctx.channel().remoteAddress() + " active !");

        ctx.channel().writeAndFlush( "Welcome to " + InetAddress.getLocalHost().getHostName() + " service!\n");

        super.channelActive(ctx);
    }


    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        log.info("\nChannel is disconnected");
        super.channelInactive(ctx);
    }




}

这里的 channelRead0(ChannelHandlerContext ctx, String msg)当客户机有消息发送过来时会调用这个方法，这个方法的名字叫的是真的差，所以netty5.0之后取消了这个名字， 5.0之后叫messageReceived。官方都说这名字叫的傻逼

channelRead0() → messageReceived()
I know. It was a silly mistake. If you are using SimpleChannelInboundHandler, you have to rename channelRead0() to messageReceived().

最后在贴一张自己在看netty实战时候画的思维导图

netty实战.png

图片还会更新，这个思维导图还没画完