when using Vue cli scaffold to create a project, after the cnpm create app command, after the project is successfully created, through the NPM run serve command, the console will report an error, sockjs.js?9be2:1606 GET http://192.168.16.105:8080/sockjs -node/info?t=1574662800493 net::ERR_ CONNECTION_ TIMED_ OUT

error analysis:
sockjs node is a JavaScript library, which provides cross browser JavaScript API and creates a low latency, full duplex communication channel between browser and web server. After the project runs, the network will always call this interface. If it is not used, this exception will be reported all the time

solution:
1) find /node_ Modules/sockjs client/dist/sockjs. JS
2) in line 1605, comment out self.xhr.send (payload) and then you can solve the

problem

try {
   // self.xhr.send(payload);
 } catch (e) { self.emit('finish', 0, ''); self._cleanup(false); } };