gulpfile.js

"use strict";

const gulp = require("gulp"),
    concat = require("gulp-concat"),
    uglify = require("gulp-uglify"),
    merge = require("merge-stream"),
    pipeline = require('readable-stream').pipeline,
    del = require("del"),
    bundleconfig = require("./distbundlesconfig.json");

function getBundles(regexPattern) {
    return bundleconfig.filter(function (bundle) {
        return regexPattern.test(bundle.outputFileName);
    });
}

function mintoDist() {
    var tasks = getBundles(/\.js$/).map(function (bundle) {
        return pipeline(
            gulp.src(bundle.inputFiles, { base: "." }),
            uglify({
                output: {
                    comments: "some"
                }
            }),
            concat(bundle.outputFileName),
            gulp.dest(".")
        );
    });
    return merge(tasks);
}

function cleanDist() {
    var files = bundleconfig.map(function (bundle) {
        return bundle.outputFileName;
    });

    return del(files, { force: true });
}

exports.buildDist = gulp.series(cleanDist, mintoDist);