SpringCloudGateway+Nacos注册与转发Netty+WebSocket

背景

项目中有个拍卖服务是长连接的，需要加入到注册中心中方便统一的管理，并且方便动态扩容。

问题

Nacos没有对长连接的服务注册的支持，需要手动实现把服务注册上线下线，感知服务状态。并需要支持域名转发WebSocket的请求。

实现

自动注册，下线服务

@Async
public void start() {
log.info("=================Netty服务开启==================");
try {
//ServerBootstrap 是一个启动类
ServerBootstrap serverBootstrap = new ServerBootstrap();
// 设置主从线程组
// ... 业务
// 注册到nacos
nettyNacosService.registerNamingService();

复制代码

          bindFuture = serverBootstrap.bind(nettyNacosService.getNettPort()).sync();
          log.info("netty监听端口:{},后台服务器启动.....", nettyNacosService.getNettPort());
      } catch (Exception e) {
          log.error("netty服务器启动异常:{}", e.getMessage());
      }
  }



  public void destroy() {
      //  将NacosNetty注销服务
      nettyNacosService.deregisterInstance();

      log.info("=================Netty服务关闭==================");
      if (bindFuture != null) {
          bindFuture.channel().closeFuture();
      }
      bossGroup.shutdownGracefully();
      workerGroup.shutdownGracefully();
  }

// 注册伪代码：
/**
* 将Netty服务注册进Nacos
*/
public void registerNamingService() {
try {
Properties properties = getNacosProperties();
NamingService namingService = NamingFactory.createNamingService(properties);

复制代码

          Instance nettyInstance = getNettyInstance();
          namingService.registerInstance(nettyInstance.getServiceName(),getGroup(),nettyInstance);
      } catch (Exception e) {
          throw new RuntimeException(e);
      }
  }

  private Properties getNacosProperties() {
      Properties properties = new Properties();
      properties.setProperty(PropertyKeyConst.SERVER_ADDR, nacosDiscoveryProperties.getServerAddr());
      properties.setProperty(PropertyKeyConst.NAMESPACE, nacosDiscoveryProperties.getNamespace());
      properties.setProperty(PropertyKeyConst.USERNAME, nacosDiscoveryProperties.getUsername());
      properties.setProperty(PropertyKeyConst.PASSWORD, nacosDiscoveryProperties.getPassword());
      return properties;
  }

  /**
   * 将NacosNetty注销服务
   */
  public void deregisterInstance() {
      try {
          Properties properties = getNacosProperties();
          NamingService namingService = NamingFactory.createNamingService(properties);

          Instance nettyInstance = getNettyInstance();
          namingService.deregisterInstance(nettyInstance.getServiceName(),getGroup(),nettyInstance);
      } catch (Exception e) {
          throw new RuntimeException(e);
      }
  }

gateway增加路由

{
"id": "web-socket",
"order": 3,
"predicates": [{
"args": {
"pattern": "/ws/**"
},
"name": "Path"
}],
"filters":[{"name":"StripPrefix","args":{"parts":"1"}}],
"uri": "lb:ws://web-socket"
}
nginx配置
这里支持长连接的配置跟http稍微有点不同。
主要看这个配置：$http_upgrade

map $http_upgrade$ connection_upgrade {
default upgrade;
'' close;
}

location /ws {
proxy_pass https://abc.com/web-socket # 这里改为对应的域名
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade; proxy_set_header Connection$ connection_upgrade;
}