index.js

const fs = require('fs');
const path = require('path');
const crypto = require('crypto');
const tinify = require('tinify');

const __home = process.env.HOME || process.env.HOMEPATH || process.env.USERPROFILE;
const apikeypath = path.join(__home, '.tinypng');
const NAME = 'Tinify Loader';

module.exports = function(content, map, meta) {
    const done = this.async();
    const options = this.getOptions() || {};

    options.cache = path.resolve(options.cache || '.cache/tinify');

    const checksum = crypto.createHash('sha1').update(content.toString('utf8')).digest('hex');
    const checksumfile = path.join(options.cache, checksum);

    if (fs.existsSync(checksumfile)) {
        fs.readFile(checksumfile, (error, body) => {
            return done(null, body);
        });
    } else {
        if (!options.apikey) {
            if (process.env.TINYPNG_KEY) {
                options.apikey = process.env.TINYPNG_KEY;
            } else if (fs.existsSync(apikeypath)) {
                options.apikey = fs.readFileSync(apikeypath, 'utf8').trim();
            }

            if (!options.apikey) {
                this.emitWarning(new Error(`${NAME}: No API key provided for TinyPNG/TinyJPG. **Images not optimized**\nYou can find instructions on getting your API key at https://www.npmjs.com/package/tinify-loader`));

                return done(null, content);
            }
        }

        if (!fs.existsSync(options.cache)) {
            options.cache.split(path.sep).reduce((current, next) => {
                const full = path.resolve(current, next);

                try {
                    if (full !== '/') {
                        fs.mkdirSync(full);
                    }
                } catch (error) {
                    if (error.code !== 'EEXIST') {
                        return done(new Error(`${NAME}: ${error.message}`));
                    }
                }

                return full;
            }, '/');
        }

        tinify.key = options.apikey;
        tinify.fromBuffer(content).toBuffer((error, body) => {
            if (error) {
                return done(new Error(`${NAME}: ${error.message}`));
            }

            fs.writeFile(checksumfile, body, err => err && console.log(err));

            return done(null, body);
        });
    }
};

module.exports.raw = true;