Callbacks

callbacks.js

// const myFetch = require('data-fetching');

function myFetch (url, callback) {
    const request = new XMLHttpRequest();
    request.onload = function(data) {
        callback(null, data);
    }
    request.onerror = function(error) {
        callback(error);
    }
    request.send();
}

function getProfile(userId) {
    myFetch(`${BACKEND_HOST}/api/user/${userId}`, (error, user) => {
        const {
            firstName,
            lastName,
            links
        } = user;

        // const firstName = user.firstName, but with ES2015
        // `${first}${last}` === String(first + '' + last)

        // links === [ { social_network: 'vk', id: '1' } ]

        // const result = {
        //     fullName: `${firstName} ${lastName}`,
        //     links: links.map(({ social_network, id }) =>
        //         getSocialNetworkUrl(social_network, id, url => {
        //             ...
        //         })
        // }
        document.write(user.firstName + ' ' + user.lastName);
    });
    // get data


    // transform data

    // show it
    
}