netty 网关 http请求 请求转发

https://netty.io/4.1/xref/io/netty/example/proxy/package-summary.html

https://netty.io/4.1/xref/io/netty/example/proxy/HexDumpProxy.html

package com.test;

import io.netty.channel.ChannelInitializer;
import io.netty.channel.socket.SocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;

public class HexDumpProxyInitializer extends ChannelInitializer<SocketChannel> {
    private final String remoteHost;
    private final int remotePort;

    public HexDumpProxyInitializer(String remoteHost, int remotePort) {
        this.remoteHost = remoteHost;
        this.remotePort = remotePort;
    }

    @Override
    public void initChannel(SocketChannel ch) {
        // 获取当前类名；
        System.out.println(this.getClass());
        ch.pipeline().addLast(
                new LoggingHandler(LogLevel.INFO),
                new HexDumpProxyInitializer(remoteHost, remotePort)
        );
    }
}

package com.test;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;

public class HexDumpProxy {
    static final int LOCAL_PORT = Integer.parseInt(System.getProperty("localPort", "8443"));
    static final String REMOTE_HOST = System.getProperty("remoteHost", "11.21.1.2");
    static final int REMOTE_PORT = Integer.parseInt(System.getProperty("remotePort", "50000"));

    public static void main(String[] args) throws Exception {
        System.err.println("Proxying *:" + LOCAL_PORT + " to " + REMOTE_HOST + ":" + REMOTE_PORT + "...");
        // Configure the bootstrap
        EventLoopGroup bossGroup = new NioEventLoopGroup(1);
        EventLoopGroup workerGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class)
                    .handler(new LoggingHandler(LogLevel.INFO))
                    .childHandler(new HexDumpProxyInitializer(REMOTE_HOST, REMOTE_PORT))
                    .childOption(ChannelOption.AUTO_READ, false)
                    .bind(LOCAL_PORT).sync().channel().closeFuture().sync();
        } finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
}