text: "use strict";
  
  let WebSocketServer = require('ws').Server;
  let port = 9000;
  let wsServer = new WebSocketServer({ port: port });
  console.log('websocket server start. port =' + port);
  
  
  wsServer.op('connection',function(ws){
      console.log('-- websocket connected --');
      ws.on('message', function(message){
          wsServer.clients.forEach(function each(client){
              if(isSame(ws,client)){
                  console.log('- skip sender -');
              }
              else{
                  client.send(message);
              }
          });
      });
  });
  
  function isSame(ws1,ws2){
      return (ws1 === ws2);
  }