Typekit font downloader

download.js

const https = require('https');
const fs = require('fs');

// https://github.com/majodev/google-webfonts-helper/blob/master/server/logic/conf.js
const FORMAT_USER_AGENTS = {
    // see http://www.dvdprojekt.de/category.php?name=Safari for a list of sample user handlers
    // test generation through running grunt mochaTest:src
    eot: 'Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0)',
    woff: 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:27.0) Gecko/20100101 Firefox/27.0',
    // must serve complete woff2 file for one variant (no unicode range support yet!)
    // see http://www.useragentstring.com/pages/Firefox/
    // see http://caniuse.com/#search=woff2
    // see http://caniuse.com/#feat=font-unicode-range
    // see https://developers.googleblog.com/2015/02/smaller-fonts-with-woff-20-and-unicode.html
    woff2: 'Mozilla/5.0 (Windows NT 6.3; rv:39.0) Gecko/20100101 Firefox/39.0',
    svg: 'Mozilla/4.0 (iPad; CPU OS 4_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/4.1 Mobile/9A405 Safari/7534.48.3',
    ttf: 'Mozilla/5.0 (Unknown; Linux x86_64) AppleWebKit/538.1 (KHTML, like Gecko) Safari/538.1 Daum/4.1'
};
const FORMAT_EXTENSIONS = {
    'truetype': 'ttf',
    'opentype': 'otf',
    'embedded-opentype': 'eot',
};

const STYLE_URL = 'https://use.typekit.net/uvx5cke.css';
const downloadedFonts = {};
process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0';

for (const format in FORMAT_USER_AGENTS) {
    const headers = {'User-Agent': FORMAT_USER_AGENTS[format]};
    https.get(STYLE_URL, {headers}, (response) => {
        if (response.statusCode !== 200) {
            throw new Error(`Request failed. Status Code: ${response.statusCode}.`);
        }

        let content = '';
        response.on('data', (chunk) => {
            content += chunk;
        });
        response.on('end', () => {
            for (const fontFaceRule of content.match(/@font-face {[^}]+}/g)) {
                const fontFamily = fontFaceRule.match(/font-family:\s*"([^"]+)"/)[1];
                const fontWeight = fontFaceRule.match(/font-weight:\s*([^;]+);/)[1];
                const fontStyle = fontFaceRule.match(/font-style:\s*([^;]+);/)[1];
                const fontUrlAndFormats = fontFaceRule.match(/url\("([^"]+)"\)\s+format\("([^"]+)"\)/g);

                for (const fontUrlAndFormat of fontUrlAndFormats) {
                    const fontUrl = fontUrlAndFormat.match(/url\("([^"]+)"\)/)[1];
                    const fontFormat = fontUrlAndFormat.match(/format\("([^"]+)"\)/)[1].toLowerCase();
                    const extension = FORMAT_EXTENSIONS[fontFormat] || fontFormat;
                    const filename = `${fontFamily}_${fontWeight}_${fontStyle}.${extension}`;

                    if (!downloadedFonts[filename]) {
                        https.get(fontUrl, (response) => {
                            console.log(`Downloaded "${fontFamily}" font family for "${fontFormat}" format in ${fontWeight} weight and ${fontStyle} style.`);
                            response.pipe(fs.createWriteStream(`downloads/${filename}`));
                        });
                    }
                }
            }
        });
    });
}

Works great, thanks!