index.js

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './Components/App';
import * as serviceWorker from './serviceWorker';
import {createStore, applyMiddleware} from 'redux';
import logger from 'redux-logger';
import thunk from 'redux-thunk';
import axios from 'axios';
import reduxPromiseMiddleware from 'redux-promise-middleware';

const initialState = {
    fetching: false,
    fetched: false,
    users: [],
    error: null
};

const reducer = (state = initialState, action) => 
{
    switch(action.type)
    {
        case "FETCH_USERS_PENDING":
            return {
                ...state,
                fetching: true
            }
        case "FETCH_USERS_REJECTED":
            return {
                ...state,
                fetching: false,
                error: action.payload
            };
        case "FETCH_USERS_FULFILLED":
            return {
                ...state,
                fetching: false,
                fetched: true,
                users: action.payload
            };
        default:
            return state;
    }
}

const middleware = applyMiddleware(reduxPromiseMiddleware(), thunk, logger);
const store = createStore(reducer, middleware);

store.dispatch({
    type: "FETCH_USERS",
    payload: axios.get('https://jsonplaceholder.typicode.com/users/').then(res => res.data)
});

/*store.dispatch(dispatch => {
	dispatch({
		type: 'FETCH_USERS_START'
    });

    axios.get('https://jsonplaceholder.typicode.com/users/')
        .then(response => response.data)
        .then(response => dispatch({
            type: "RECEIVE_USERS",
            payload: response
        }))
        .catch(error => dispatch({
            type: "FETCH_USERS_ERROR",
            payload: error
        }))
});*/

ReactDOM.render(<App />, document.getElementById('root'));

// If you want your app to work offline and load faster, you can change
// unregister() to register() below. Note this comes with some pitfalls.
// Learn more about service workers: http://bit.ly/CRA-PWA
serviceWorker.unregister();