react-native: import syntax throws when importing socket.io if debugger is not attached

@Mokto Try this:

const io = socket(SOCKET_IP,{
  jsonp: false,
  transports: ['websocket']
})

@tarkanlar

//you miss this part, define the environment socket.io works
//if not work, try put the following line into another file and import it
window.navigator.userAgent = "react-native";

const io = socket(SOCKET_IP,{
  jsonp: false,
  transports: ['websocket']
})

The code that works:

import React from 'react-native';
import './UserAgent';

import io from 'socket.io-client/socket.io';

exports.createConnection = function(host, port, options) {
    var stream = io('ws://'+host+':'+port, {
        jsonp: false,
        reconnection: true,
        reconnectionAttempts: 32,
        reconnectionDelay: 50,
        reconnectionDelayMax: 30000,
        timeout: 2000,
        transports: ['websocket']
    });
    return stream;
}

you have to write “ws://” instead of “http://”. And add “transports: [‘websocket’]”. It should works.

@chezhe thanks so much, it works like a charm ! I’ve been looking for solution and no hope until i saw this xD

@adamterlson I can confirm that i’ve used socket.io with react native and had no issues.

The only caveat that I ran into earlier was that userAgent was undefined. I managed a temporary work around by adding window.navigator.userAgent = "react-native";

Here is an article by @browniefed that might help. http://browniefed.com/blog/2015/05/16/react-native-and-socket-dot-io/

In the past i’ve worked with https://www.npmjs.com/package/react-native-swift-socketio and it worked fine as well.

Hope this helps!

@adamterlson As far as I understand, all imports are hoisted to the top, while requires are not. Hence, the reason it’s not working with import syntax is, socket.io is being required and executed even before window.navigator.userAgent = "react-native" is called, and throws error.

I guess it only happens in debugger because there might be a delay somewhere while communicating via the bridge, and there is not enough delay when running on phone to cause this. I might be wrong though.

Feel free to close the issue if this answers your question.

@christopherdo Well Socket IO works fine, but that’s not really the issue. The question is why there’s inconsistent behavior from RN depending on import vs require usage and whether a debugger is attached. Does that not seem strange?

Thanks for the help!