graphRestoration.js

Math.getRandomInt = (min, max) => {
    /* getRandomInt(11, 17) => output includes 11 and 17 */
    return Math.floor(Math.random() * (max - min + 1)) + min;
};

//  Vue.js   Nurislam   Node.js  Artur          Islam      React_Na Artur
//  books[0].authors[0].books[1].authors[1] === persons[2].books[0].authors[1];

function fetchBooks() {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            resolve([{
                uid: `a`,
                title: `Vue.js`,
                authors: [0]
            }, {
                uid: `b`,
                title: `React Native`,
                authors: [1, 2]
            }, {
                uid: `c`,
                title: `Node.js`,
                authors: [0, 1]
            }, {
                uid: `d`,
                title: `PHP 7.1`,
                authors: [1, 2]
            }]);
        }, Math.getRandomInt(300, 500));
    });
}
function fetchPersons() {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            resolve([{
                uid: `a`,
                name: `Nurislam`,
                books: [0, 2]
            }, {
                uid: `b`,
                name: `Artur`,
                books: [1, 2, 3]
            }, {
                uid: `c`,
                name: `Islam`,
                books: [1, 3]
            }]);
        }, Math.getRandomInt(200, 400));
    });
}


// ur code here
async function _books() {
    const books = await fetchBooks();
    // or/and here
}
async function _persons() {
    const persons = await fetchPersons();
    // or/and here
}

async function main() {
    setTimeout(_books, Math.getRandomInt(100, 200));
    setTimeout(_persons, Math.getRandomInt(100, 200));
}