3.js

var Main = React.createClass({
    getInitialState() {
        //already shown    
    },
    componentDidMount() {        
        var socket = io();
        
        var props = this.props;
        var users = this.state.users;
        var messages = this.state.messages;
        var self = this;
        
        var socketIdStream = Rx.Observable.create(observer => {
            socket.on('my socketId', data => { observer.onNext(data); });
        });  
        
        socketIdStream.subscribe(data => {            
            socket.emit('client connect', {
                nickname: props.nickname,
                socketId: data.socketId,
                connectTime: data.connectTime 
            });
        });
        
        var socketAllUsersStream = Rx.Observable.create(observer => {
            socket.on('all users', data => { observer.onNext(data); });            
        });

        socketAllUsersStream.subscribe(data => {
            self.setState({users: data});
        });
        
        var socketMessageStream = Rx.Observable.create(observer => {
            socket.on('message', data => { observer.onNext(data); });            
        });
        
        socketMessageStream.subscribe(data => {
            messages.push(data);
            self.setState(messages); //data is {'message': text, 'who': nickname, 'timestamp': Date.now}
        });                
    },
    render() {
        //already shown
    }
});