I need to know how to make this work with react.It's the official demo from redux-observable

src_actions_index.js

import * as ActionTypes from "../ActionTypes"


export const fetchUser = username => ({ type: ActionTypes.FETCH_USER, payload: username });
export const fetchUserFulfilled = payload => ({ type: ActionTypes.FETCH_USER_FULFILLED, payload });

src_ActionTypes.js

export const FETCH_USER = 'FETCH_USER';
export const FETCH_USER_FULFILLED = 'FETCH_USER_FULFILLED';

src_App.css

.App {
  text-align: center;
}

.App-logo {
  animation: App-logo-spin infinite 20s linear;
  height: 80px;
}

.App-header {
  background-color: #222;
  height: 150px;
  padding: 20px;
  color: white;
}

.App-intro {
  font-size: large;
}

@keyframes App-logo-spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

src_App.js

import React, { Component } from 'react';
import { combineReducers, createStore, applyMiddleware} from 'redux';
import { combineEpics, createEpicMiddleware } from "redux-observable"
import { fetchUser } from "./actions";
import { user } from './reducers/reducer_user';
import 'rxjs';
import logo from './logo.svg';
import './App.css';

class App extends Component {
    constructor(props) {
       super(props);
    }
    render() {
        const { user } = this.props;
    return (
      <div className="App">
          <div>
              <h1>Fetch User Demo</h1>
              <button onClick={fetchUser}>
                  Fetch User Info
              </button>
              <div>
              <textarea>{JSON.stringify(store.user, null, 2)}</textarea>
              </div>
          </div>
      </div>
    );
    }
}

export default App;

src_App.test.js

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';

it('renders without crashing', () => {
  const div = document.createElement('div');
  ReactDOM.render(<App />, div);
});

src_configureStore.js

import { createBrowserHistory } from 'history'
import { createStore, applyMiddleware, compose } from 'redux';
import { createEpicMiddleware } from 'redux-observable';
import { routerMiddleware } from 'react-router-redux';
import { rootReducer } from './reducers';
import { rootEpic } from './epics';
const history = createBrowserHistory();

const epicMiddleware = createEpicMiddleware(rootEpic);

export default function configureStore() {
    const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
    const store = createStore(
        rootReducer,
        composeEnhancers(
            applyMiddleware(
                epicMiddleware,
                routerMiddleware(history)
            )
        )
    );
    return store;
}

src_epics_epic_user_fetch.js

import * as ActionTypes from '../ActionTypes';
import {fetchUserFulfilled} from "../actions";
import 'rxjs';
import { ajax } from 'rxjs/observable/dom/ajax';
export default function fetchUserEpic(action$) {
    return action$.ofType(ActionTypes.FETCH_USER)
        .flatMap(action =>
            ajax.getJSON(`https://api.github.com/users/${action.payload}`)
                .map(response => fetchUserFulfilled(response))
        );
}

src_epics_index.js

import { combineEpics } from 'redux-observable';
import fetchUserEpic from './epic_user_fetch';


export const rootEpic = combineEpics(
    fetchUserEpic
);

src_index.js

import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import { createBrowserHistory } from 'history'
import './index.css';
import 'rxjs'
import App from './App';
import registerServiceWorker from './registerServiceWorker';
import configureStore from './configureStore';
const store = configureStore();
const history = createBrowserHistory();

ReactDOM.render(<Provider store={store}><App /></Provider>, document.getElementById('root'));
registerServiceWorker();

src_reducers_index.js

import { combineReducers } from 'redux';
import { routerReducer } from 'react-router-redux';
import users from './reducer_user';
export const rootReducer = combineReducers({
    users,
    routing: routerReducer
});

src_reducers_reducer_user.js

import * as ActionTypes from "../ActionTypes";

export default function users(state={}, action) {
    switch (action.type) {
        case ActionTypes.FETCH_USER_FULFILLED:
            return {
                ...state,
                // `login` is the username
                [action.payload.login]: action.payload
            };

        default:
            return state;
    }
};