socket.io-client keeping on connecting when using

Question

I want to use the websocket in my RN project. And I did it using the ws at server side and the RN built-in websocket implementation. But it seems not so convinient since I use socket.io before. So I tried to use socket.io: In RN:

import './userAgent'
import io from "socket.io-client/socket.io"

In component:

    componentDidMount() {
     this.socket = io('https://localhost:4080',{jsonp: false});
     this.socket.on('hello', (msg) =>{
       this.setState({response:msg})

     });
    }

In the server:

  io.on('connection', function(socket){
   socket.emit('hello','hello world')
   console.log('a user connected');
   socket.on('disconnect',function(){
     console.log('user disconnected')
   })
  })

And in userAgent.js

window.navigator.userAgent = 'react-native';

That is just the result I googled and they said it will work. But for me, the chrome debugger stopped at:

function load() {
 var r;
 try {
  r = exports.storage.debug;
 } catch(e) {}
 return r;
}

And it says the storage is not defined. Then I looked into the socket.io.js and find that the exports.storage is window.localStorage. So I disabled the remote js debug, and the code began running.

But the server continues to log : a user connected . as if my RN app is keeping on connecting to the server. And it seems the socket.on() did not work at client side.

react-native version:0.27.2

socket.io-client version:1.4.8

Anyone knows where is going wrong?

Answer 1

Well,finally I found the solution after looking through the socket.io source. It seems that the socket.io does not use 'websocket' as transport defaultly. It will use the 'polling' in my case, so just explicityly set it :

 componentDidMount() {
    var socket = io('http://localhost:4080', { jsonp: false, transports: ['websocket'] })
    socket.on('hello', (msg) => {
       //do something
    });
}

Now it works. But what still confuses me is that in brower client I do not set the transports and it just work well but in react-native it doesn't. Not figured out why.