2.（选做）使用 netty 实现后端 http 访问（代替上一步骤）

bl03615 · bl03615 · commit 1b359bab10d0 · 2021-08-22T15:25:35.000+08:00
diff --git a/02nio/nio02/src/main/java/io/github/kimmking/gateway/client/HttpClientHandler.java b/02nio/nio02/src/main/java/io/github/kimmking/gateway/client/HttpClientHandler.java
@@ -0,0 +1,34 @@
+package io.github.kimmking.gateway.client;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.handler.codec.http.*;
+import io.netty.util.CharsetUtil;
+
+import java.net.URI;
+
+public class HttpClientHandler extends ChannelInboundHandlerAdapter {
+
+    @Override
+    public void channelActive(ChannelHandlerContext ctx) throws Exception {
+        URI uri = new URI("/user/get");
+        FullHttpRequest request = new DefaultFullHttpRequest(HttpVersion.HTTP_1_0, HttpMethod.GET, uri.toASCIIString());
+        request.headers().add(HttpHeaderNames.CONNECTION,HttpHeaderValues.KEEP_ALIVE);
+        request.headers().add(HttpHeaderNames.CONTENT_LENGTH,request.content().readableBytes());
+        ctx.writeAndFlush(request);
+    }
+
+    @Override
+    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+        System.out.println("msg ->" + msg);
+
+        if (msg instanceof FullHttpRequest) {
+            FullHttpResponse response = (FullHttpResponse) msg;
+            ByteBuf buf = response.content();
+            String result = buf.toString(CharsetUtil.UTF_8);
+            System.out.println("response -> " + result);
+
+        }
+    }
+}
diff --git a/02nio/nio02/src/main/java/io/github/kimmking/gateway/client/NettyClientTest.java b/02nio/nio02/src/main/java/io/github/kimmking/gateway/client/NettyClientTest.java
@@ -0,0 +1,48 @@
+package io.github.kimmking.gateway.client;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.*;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.socket.nio.NioSocketChannel;
+import io.netty.handler.codec.http.HttpClientCodec;
+import io.netty.handler.codec.http.HttpContentDecompressor;
+import io.netty.handler.codec.http.HttpObjectAggregator;
+
+public class NettyClientTest {
+
+    public static void start(String host,int port){
+
+        EventLoopGroup group = new NioEventLoopGroup();
+
+        try {
+            Bootstrap b = new Bootstrap();
+            b.group(group)
+                    .channel(NioSocketChannel.class)
+                    .option(ChannelOption.SO_KEEPALIVE,true)
+                    .handler(new ChannelInitializer<Channel>() {
+                @Override
+                protected void initChannel(Channel ch) throws Exception {
+                    ch.pipeline().addLast(new HttpClientCodec());
+                    ch.pipeline().addLast(new HttpObjectAggregator(65536));
+                    ch.pipeline().addLast(new HttpContentDecompressor());
+                    ch.pipeline().addLast(new HttpClientHandler());
+                }
+            });
+
+            ChannelFuture future = b.connect(host, port).sync();
+            ChannelFuture channelFuture = future.channel().closeFuture().sync();
+
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        } finally {
+            System.out.println("关闭线程组");
+            group.shutdownGracefully();
+        }
+
+    }
+
+    public static void main(String[] args) {
+        start("localhost",8888);
+    }
+
+}
diff --git a/02nio/nio02/src/main/java/io/github/kimmking/gateway/outbound/httpclient4/HttpOutboundHandler.java b/02nio/nio02/src/main/java/io/github/kimmking/gateway/outbound/httpclient4/HttpOutboundHandler.java
@@ -79,9 +79,11 @@ public void handle(final FullHttpRequest fullRequest, final ChannelHandlerContex
 
         String backendUrl = router.route(this.backendUrls,weights);
         final String url = backendUrl + fullRequest.uri();
+
+        System.out.println("被访问的url:"+url);
+
         filter.filter(fullRequest, ctx);
 
-        //TODO ExcutorService now,use netty instead
         proxyService.submit(()->fetchGet(fullRequest, ctx, url));
     }
     
