基於Netty4的HttpServer和HttpClient的簡單實現
阿新 • • 發佈：2019-01-27
使用的Netty的版本：netty-4.0.23.Final.tar.bz2 ‐ 15-Aug-2014 (Stable, Recommended)
Http 訊息格式：
Http request:
Method path-to-resource HTTPVersion-number Header-name-1: value1 Header-name-2: value2 Optional request body
Http response:
HTTP/Version-number response-code response-phrase Header-name-1: value1 Header-name-2: value2 Optional response body
實現一個簡單的Http請求及響應過程：
1、Client向Server傳送http請求。
2、Server端對http請求進行解析。
3、Server端向client傳送http響應。
4、Client對http響應進行解析。
Netty中Http request訊息格式：
Netty中Http response訊息格式：
程式碼例項：
Http Server：
package com.netty.test; import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory; import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.EventLoopGroup; import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioServerSocketChannel; import io.netty.handler.codec.http.HttpRequestDecoder; import io.netty.handler.codec.http.HttpResponseEncoder; public class HttpServer { private static Log log = LogFactory.getLog(HttpServer.class); public void start(int port) throws Exception { EventLoopGroup bossGroup = new NioEventLoopGroup(); EventLoopGroup workerGroup = new NioEventLoopGroup(); try { ServerBootstrap b = new ServerBootstrap(); b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class) .childHandler(new ChannelInitializer<SocketChannel>() { @Override public void initChannel(SocketChannel ch) throws Exception { // server端傳送的是httpResponse，所以要使用HttpResponseEncoder進行編碼 ch.pipeline().addLast(new HttpResponseEncoder()); // server端接收到的是httpRequest，所以要使用HttpRequestDecoder進行解碼 ch.pipeline().addLast(new HttpRequestDecoder()); ch.pipeline().addLast(new HttpServerInboundHandler()); } }).option(ChannelOption.SO_BACKLOG, 128) .childOption(ChannelOption.SO_KEEPALIVE, true); ChannelFuture f = b.bind(port).sync(); f.channel().closeFuture().sync(); } finally { workerGroup.shutdownGracefully(); bossGroup.shutdownGracefully(); } } public static void main(String[] args) throws Exception { HttpServer server = new HttpServer(); log.info("Http Server listening on 8844 ..."); server.start(8844); } }
響應請求的HttpServerInboundHandler：
package com.netty.test; import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION; import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_LENGTH; import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE; import static io.netty.handler.codec.http.HttpResponseStatus.OK; import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.handler.codec.http.DefaultFullHttpResponse; import io.netty.handler.codec.http.FullHttpResponse; import io.netty.handler.codec.http.HttpContent; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpHeaders.Values; import io.netty.handler.codec.http.HttpRequest; public class HttpServerInboundHandler extends ChannelInboundHandlerAdapter { private static Log log = LogFactory.getLog(HttpServerInboundHandler.class); private HttpRequest request; @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { if (msg instanceof HttpRequest) { request = (HttpRequest) msg; String uri = request.getUri(); System.out.println("Uri:" + uri); } if (msg instanceof HttpContent) { HttpContent content = (HttpContent) msg; ByteBuf buf = content.content(); System.out.println(buf.toString(io.netty.util.CharsetUtil.UTF_8)); buf.release();
String res = "I am OK"; FullHttpResponse response = new DefaultFullHttpResponse(HTTP_1_1, OK, Unpooled.wrappedBuffer(res.getBytes("UTF-8"))); response.headers().set(CONTENT_TYPE, "text/plain"); response.headers().set(CONTENT_LENGTH, response.content().readableBytes()); if (HttpHeaders.isKeepAlive(request)) { response.headers().set(CONNECTION, Values.KEEP_ALIVE); } ctx.write(response); ctx.flush(); } } @Override public void channelReadComplete(ChannelHandlerContext ctx) throws Exception { ctx.flush(); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { log.error(cause.getMessage()); ctx.close(); } }
Http Client：
package com.netty.test; import io.netty.bootstrap.Bootstrap; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; 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.http.DefaultFullHttpRequest; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpMethod; import io.netty.handler.codec.http.HttpRequestEncoder; import io.netty.handler.codec.http.HttpResponseDecoder; import io.netty.handler.codec.http.HttpVersion; import java.net.URI; public class HttpClient { public void connect(String host, int port) throws Exception { EventLoopGroup workerGroup = new NioEventLoopGroup(); try { Bootstrap b = new Bootstrap(); b.group(workerGroup); b.channel(NioSocketChannel.class); b.option(ChannelOption.SO_KEEPALIVE, true); b.handler(new ChannelInitializer<SocketChannel>() { @Override public void initChannel(SocketChannel ch) throws Exception { // 客戶端接收到的是httpResponse響應，所以要使用HttpResponseDecoder進行解碼 ch.pipeline().addLast(new HttpResponseDecoder()); // 客戶端傳送的是httprequest，所以要使用HttpRequestEncoder進行編碼 ch.pipeline().addLast(new HttpRequestEncoder()); ch.pipeline().addLast(new HttpClientInboundHandler()); } }); // Start the client. ChannelFuture f = b.connect(host, port).sync(); URI uri = new URI("http://127.0.0.1:8844"); String msg = "Are you ok?"; DefaultFullHttpRequest request = new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, uri.toASCIIString(), Unpooled.wrappedBuffer(msg.getBytes("UTF-8"))); // 構建http請求 request.headers().set(HttpHeaders.Names.HOST, host); request.headers().set(HttpHeaders.Names.CONNECTION, HttpHeaders.Values.KEEP_ALIVE); request.headers().set(HttpHeaders.Names.CONTENT_LENGTH, request.content().readableBytes()); // 傳送http請求 f.channel().write(request); f.channel().flush(); f.channel().closeFuture().sync(); } finally { workerGroup.shutdownGracefully(); } } public static void main(String[] args) throws Exception { HttpClient client = new HttpClient(); client.connect("127.0.0.1", 8844); } }
處理Server響應的HttpClientInboundHandler：
package com.netty.test; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.handler.codec.http.HttpContent; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpResponse; public class HttpClientInboundHandler extends ChannelInboundHandlerAdapter { @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { if (msg instanceof HttpResponse) { HttpResponse response = (HttpResponse) msg; System.out.println("CONTENT_TYPE:" + response.headers().get(HttpHeaders.Names.CONTENT_TYPE)); } if(msg instanceof HttpContent) { HttpContent content = (HttpContent)msg; ByteBuf buf = content.content(); System.out.println(buf.toString(io.netty.util.CharsetUtil.UTF_8)); buf.release(); } } }
log4j的配置：
# Root logger option
log4j.rootLogger=INFO, stdout, file
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
log4j.appender.file = org.apache.log4j.DailyRollingFileAppender
log4j.appender.file.File = logs/log.log
log4j.appender.file.Append = true
log4j.appender.file.Threshold = INFO
log4j.appender.file.layout = org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} %5p %c{1}:%L - %m%n
來源：http://www.cnblogs.com/luxiaoxun/p/3959450.html