Adaptando un callback a una promesa

adapt_promise.js

const request = require('request');

function leer(url) {
    return new Promise((resolve, reject) => {
        request(url, function (err, response) {
            if (err) {
                reject(err)
            } else {
                resolve(response);
            }
        })
    });
}

leer('https://google.com')
    .then(response => console.log(response))
    .catch(err => console.log(err));