webpack dev-server代理websocket问题

proxyTable: {
      //多后端配置
      '/a': {
        //target: http://xxxxx/xxxxxx
        target: config.a_target,//如上一行写成地址即可
        //changeOrigin: true,
        pathRewrite: {
          '^/a':'/'
        }
      },
      '/b':{
        target:config.b_target,
        pathRewrite: {
          '^/b':'/'
        }
      },
      '/c':{
        target: config.c_target,
        ws:true,//支持websokcet
        changeOrigin: true,
        pathRewrite: {
          '^/c':'/'
        }
      },
      '/':{
        target: config.real_target, 
        //ws: true,//支持websocket
        changeOrigin: true,
        pathRewrite: {
        }
      },

//根据http协议判断是否为ws或wss
let proto = document.location.protocol == 'http:'? 'ws:': 'wss:';
//取地址+端口，配置80端口时port是空的，所以判断一下
let address = document.location.port? 
document.location.hostname + ':' + document.location.port:  document.location.hostname ;
//拼接请求地址
const wsuri = proto + "//" + address + "/c/"+this.robotId;
console.log(wsuri);
this.websock = new WebSocket(wsuri);

'/':{
        target: config.real_target, 
        //ws: true,//注释掉，不启用即可
        changeOrigin: true,
        pathRewrite: {
        }
      },