grunt-contrib-kraken/tasks/kraken.js

Grunt plugin to optimize all your images with the powerful Kraken.io API

var fs = require('fs'),
    os = require('os'),
    isGIF = require('is-gif'),
    isPNG = require('is-png'),
    isJPG = require('is-jpg'),
    async = require('async'),
    chalk = require('chalk'),
    pretty = require('pretty-bytes'),
    Kraken = require('kraken'),
    request = require('request');

module.exports = function (grunt) {
    grunt.registerMultiTask('kraken', 'Grunt plugin to optimize all your images with the powerful Kraken.io API', function () {
        var done = this.async(),
            files = this.files,
            options = this.options({
                lossy: false
            });

        var total = {
            bytes: 0,
            kraked: 0,
            files: 0
        };

        async.forEachLimit(files, os.cpus().length, function (file, next) {
            var isSupported = !isGIF(file.src[0]) || !isPNG(file.src[0]) || !isJPG(file.src[0]);

            if (!isSupported) {
                grunt.warn('Skipping unsupported image ' + file.src[0]);
                return next();
            }

            var kraken = new Kraken({
                api_key: options.key,
                api_secret: options.secret
            });

            var opts = {
                file: file.src[0],
                lossy: options.lossy || false,
                wait: true
            };

            kraken.upload(opts, function (data) {
                if (!data.success) {
                    grunt.warn('Error in file ' + file.src[0] + ': ' + data.message || data.error);
                    return next();
                }

                var originalSize = data.original_size,
                    krakedSize = data.kraked_size,
                    savings = data.saved_bytes;

                var percent = (((savings) * 100) / originalSize).toFixed(2),
                    savedMsg = 'saved ' + pretty(savings) + ' - ' + percent + '%',
                    msg = savings > 0 ? savedMsg : 'already optimized';

                total.bytes += originalSize;
                total.kraked += krakedSize;
                total.files++;

                request(data.kraked_url, function (err) {
                    if (err) {
                        grunt.warn(err + ' in file ' + file.src[0]);
                        return next();
                    }

                    grunt.log.writeln(chalk.green('✔ ') + file.src[0] + chalk.gray(' (' + msg + ')'));
                    process.nextTick(next);
                }).pipe(fs.createWriteStream(file.dest));
            });
        }, function (err) {
            if (err) {
                grunt.warn(err);
            }

            var percent = (((total.bytes - total.kraked) * 100) / total.bytes).toFixed(2);
                savings = total.bytes - total.kraked;
                msg = 'All done. Kraked ' + total.files + ' image';

            msg += total.files === 1 ? '' : 's';
            msg += chalk.gray(' (saved ' + pretty(savings) + ' - ' + percent + '%)');

            grunt.log.writeln(msg);
            done();
        });
    });
};