Question

我能够通过与服务器的连接编写我的http请求，但是我无法从服务器读取响应（不确定是否有任何响应）..如何检查然后读取它？我的服务器正在回复json。

客户代码：

public class NettyClient {



      public static void main(String[] args) throws Exception {
           URI uri = new URI("http://myurl.com/v1/v2?param1=value1");          
           String scheme = uri.getScheme() == null? "http" : uri.getScheme();
           String host = uri.getHost();
            int port = 443;

            boolean ssl = "https".equalsIgnoreCase(scheme);

         // Configure the client.
            EventLoopGroup group = new NioEventLoopGroup();
            try {
                Bootstrap b = new Bootstrap();
                b.group(group)
                 .channel(NioSocketChannel.class)
                 .handler(new NettyClientInitializer(false));
                // Make the connection attempt.
                Channel ch = b.connect(host, port).sync().channel();
                // Prepare the HTTP request.
                HttpRequest request = new DefaultHttpRequest(
                        HttpVersion.HTTP_1_1, HttpMethod.GET, "http://myurl.com/v1/v2?param1=value1");
                request.headers().set(HttpHeaders.Names.HOST, host);
                request.headers().set(HttpHeaders.Names.CONNECTION, HttpHeaders.Values.KEEP_ALIVE);            
                //request.headers().set(HttpHeaders.Names.ACCEPT_ENCODING, HttpHeaders.Values.GZIP);

                // Send the HTTP request.
                ch.writeAndFlush(request);

                // Wait for the server to close the connection.
                ch.closeFuture().sync();
            } finally {
                // Shut down executor threads to exit.
                group.shutdownGracefully();
            }
      }
}

初始化代码：

public class NettyClientInitializer extends ChannelInitializer<SocketChannel> {

    private final boolean ssl;

    public NettyClientInitializer(boolean ssl) {
        this.ssl = ssl;
    }

    @Override
    public void initChannel(SocketChannel ch) throws Exception {
        // Create a default pipeline implementation.
        ChannelPipeline p = ch.pipeline();

        p.addLast("log", new LoggingHandler(LogLevel.INFO));
        // Enable HTTPS if necessary.
        /*
        if (ssl) {
            SSLEngine engine =
                SecureChatSslContextFactory.getClientContext().createSSLEngine();
            engine.setUseClientMode(true);

            p.addLast("ssl", new SslHandler(engine));
        }
*/
        p.addLast("codec", new HttpClientCodec());

        // Remove the following line if you don't want automatic content decompression.
       // p.addLast("inflater", new HttpContentDecompressor());

        // Uncomment the following line if you don't want to handle HttpChunks.
        //p.addLast("aggregator", new HttpObjectAggregator(1048576));
        p.addLast("handler", new NettyClientHandler());
    }
}

处理程序代码：

public class NettyClientHandler extends SimpleChannelInboundHandler<HttpObject> {

    @Override
    public void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
        if (msg instanceof HttpResponse) {
            HttpResponse response = (HttpResponse) msg;

            System.out.println("STATUS: " + response.getStatus());
            System.out.println("VERSION: " + response.getProtocolVersion());
            System.out.println();

            if (!response.headers().isEmpty()) {
                for (String name: response.headers().names()) {
                    for (String value: response.headers().getAll(name)) {
                        System.out.println("HEADER: " + name + " = " + value);
                    }
                }
                System.out.println();
            }

            if (HttpHeaders.isTransferEncodingChunked(response)) {
                System.out.println("CHUNKED CONTENT {");
            } else {
                System.out.println("CONTENT {");
            }
        }
        if (msg instanceof HttpContent) {
            HttpContent content = (HttpContent) msg;

            System.out.print(content.content().toString(CharsetUtil.UTF_8));
            System.out.flush();

            if (content instanceof LastHttpContent) {
                System.out.println("} END OF CONTENT");
            }
        }
    }

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


}

在控制台中，我可以看到正在写入的请求，但在此之后刷新了请求，然后通道处于非活动状态，然后取消注册。

原因可能是我的查询参数没有被发送或json问题，或者我在代码中遗漏了什么？

Answer 1

问题可能在于您在端口443上连接到服务器

int port = 443;
...
Channel ch = b.connect(host, port).sync().channel();

但是你的NettyClientInitializer不支持SSL（它已经在管道中注释掉）并且你构建它就像没有使用SSL一样

new NettyClientInitializer(false)

如果将端口更改为80，则代码可以正常工作。

无法使用netty在http客户端中读取响应

1 个答案: