openeuler/netty repository overview

⁠Quick reference

• The official Netty docker image.

• Maintained by: openEuler CloudNative SIG⁠.

• Where to get help: openEuler CloudNative SIG⁠, openEuler⁠.

⁠Netty | openEuler

Current Netty docker images are built on the openEuler⁠. This repository is free to use and exempted from per-user rate limits.

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients.

Learn more about Netty on Netty Website⁠⁠.

⁠Supported tags and respective Dockerfile links

The tag of each netty docker image is consist of the version of netty and the version of basic image. The details are as follows

⁠Usage

In this usage, users can select the corresponding {Tag} based on their requirements.

• Pull the openeuler/netty image from docker

  docker pull openeuler/netty:{Tag}
  

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• Add the Netty dependency:

  **Maven：

  <dependency>
    <groupId>io.netty</groupId>
    <artifactId>netty-all</artifactId>
    <version>${NETTY_VERSION}</version>
  </dependency>
  

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  Gradle:**

  implementation 'io.netty:netty-all:${NETTY_VERSION}'
  

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• Write a simple server

  EchoServer.java：

  public class EchoServer {
      private final int port;
    
      public EchoServer(int port) {
          this.port = port;
      }
    
      public void start() 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) {
                       ch.pipeline().addLast(new EchoServerHandler());
                   }
               });
    
              ChannelFuture f = b.bind(port).sync();
              f.channel().closeFuture().sync();
          } finally {
              bossGroup.shutdownGracefully();
              workerGroup.shutdownGracefully();
          }
      }
    
      public static void main(String[] args) throws Exception {
          new EchoServer(8080).start(); 
      }
  }
  

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  EchoServerHandler.java

  public class EchoServerHandler extends ChannelInboundHandlerAdapter {
      @Override
      public void channelRead(ChannelHandlerContext ctx, Object msg) {
          ctx.write(msg);
      }
    
      @Override
      public void channelReadComplete(ChannelHandlerContext ctx) {
          ctx.flush();
      }
    
      @Override
      public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
          cause.printStackTrace();
          ctx.close();
      }
  }
  

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• Run the server

  Directly run the main method in the EchoServer class. Test via command line:

  telnet localhost 8080
  

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  Any input will be echoed back by the server.

⁠Question and answering

If you have any questions or want to use some special features, please submit an issue or a pull request on openeuler-docker-images⁠.