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基于Netty构建HTTP访问分为两类,使用浏览器访问的和使用Netty客户端访问。在介绍之前,先简单说一下如何使用Netty实现Http服务的。
Netty的Http服务的流程是:
1、Client向Server发送http请求。
2、Server端对http请求进行解析。
3、Server端向client发送http响应。
4、Client对http响应进行解析。

下图是网上复制别人的

 

 

 

 

直接上代码:

TestHttpServerHandler
package com.atguigu.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

import java.net.URI;

/*
说明
1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter
2. HttpObject 客户端和服务器端相互通讯的数据被封装成 HttpObject
 */
public class TestHttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {


    //channelRead0 读取客户端数据
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {


        System.out.println("对应的channel=" + ctx.channel() + " pipeline=" + ctx
        .pipeline() + " 通过pipeline获取channel" + ctx.pipeline().channel());

        System.out.println("当前ctx的handler=" + ctx.handler());

        //判断 msg 是不是 httprequest请求
        if(msg instanceof HttpRequest) {

            System.out.println("ctx 类型="+ctx.getClass());

            System.out.println("pipeline hashcode" + ctx.pipeline().hashCode() + " TestHttpServerHandler hash=" + this.hashCode());

            System.out.println("msg 类型=" + msg.getClass());
            System.out.println("客户端地址" + ctx.channel().remoteAddress());

            //获取到
            HttpRequest httpRequest = (HttpRequest) msg;
            //获取uri, 过滤指定的资源
            URI uri = new URI(httpRequest.uri());
            if("/favicon.ico".equals(uri.getPath())) {
                System.out.println("请求了 favicon.ico, 不做响应");
                return;
            }
            //回复信息给浏览器 [http协议]

            ByteBuf content = Unpooled.copiedBuffer("hello, 我是服务器", CharsetUtil.UTF_8);

            //构造一个http的相应,即 httpresponse
            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);

            response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain;charset=UTF-8");
            response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());

            //将构建好 response返回
            ctx.writeAndFlush(response);

        }
    }



}

 

TestServerInitializer

TestServerInitializer
import io.netty.channel.ChannelInitializer;import io.netty.channel.ChannelPipeline;import io.netty.channel.socket.SocketChannel;import io.netty.handler.codec.http.HttpServerCodec;public class TestServerInitializer extends ChannelInitializer<SocketChannel> {    @Override    protected void initChannel(SocketChannel ch) throws Exception {        //向管道加入处理器        //得到管道        ChannelPipeline pipeline = ch.pipeline();        //加入一个netty 提供的httpServerCodec codec =>[coder - decoder]        //HttpServerCodec 说明        //1. HttpServerCodec 是netty 提供的处理http的 编-解码器        pipeline.addLast("MyHttpServerCodec",new HttpServerCodec());        //2. 增加一个自定义的handler        pipeline.addLast("MyTestHttpServerHandler", new TestHttpServerHandler());        System.out.println("ok~~~~");    }}

TestHttpServer

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;

public class TestServer {
    public static void main(String[] args) throws Exception {

        EventLoopGroup bossGroup = new NioEventLoopGroup(1);
        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try {
            ServerBootstrap serverBootstrap = new ServerBootstrap();

            serverBootstrap.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class).childHandler(new TestServerInitializer());

            ChannelFuture channelFuture = serverBootstrap.bind(6668).sync();
            
            channelFuture.channel().closeFuture().sync();

        }finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
}

 

 注意:

1.如果6668端口浏览器无法访问:参照 《window的对外开放端口》

2.浏览器乱码请设置浏览器的charset,消息头中

3.访问发现每次都有两次请求: 另外一个请求时浏览器的图标请求: 

/favicon.ico, 可以F12看,每次都会有
posted on 2020-06-06 10:45  楼子湾  阅读(79)  评论(0编辑  收藏