gulpfile.js

"use strict";

var gulp = require("gulp"),
	fs = require("fs"),
	watch = require("gulp-watch"),
	plugins = require("gulp-load-plugins")(),
	babelify = require("babelify"),
	browserify = require("browserify"),
	watchify = require("watchify"),
	source = require("vinyl-source-stream"),
	buffer = require("vinyl-buffer");

gulp.task("watchjs", () => {
	watchReadDirectory();

	watch(["./*.js"], {events: ['add', 'unlink']}, (e, done) => {
		var file = getFileName(e.path);
		if (e.event == "add") {
			plugins.util.log(` added ${file}`);
			startWatchify(file);
		} else if (e.event == "unlink") {
			plugins.util.log(` removed ${file}`);
			var outpath = "../../../public/js/" + file;
			fs.unlink(outpath, (err) => {
				if (err != null) {
					plugins.util.log(err);
				}
			});
		}
	});
});

var getFileName = (path) => {
	var s = path.split("/");
	return s[s.length -1];
};

var watchReadDirectory = () => {
	fs.readdir(".", (err, files) => {
		files.filter((file) => {
			return fs.statSync(file).isFile() && /.*\.js$/.test(file) && !/^gulpfile\.js$/.test(file)
		}).forEach((file) => {
			startWatchify(file);
		});
	});
};

var startWatchify = (file) => {
	const srcDir = ".";
	const outDir = "../../../public/js";
	if (file == "gulpfile.js") {
		return;
	}

	let browserifyOp = {
		entries: [srcDir + "/" + file],
		transform: babelify.configure({presets: ["react"]}),
		debug: true,
		cache: {},
		packageCache: {},
	};

	let watchifyStream = watchify(browserify(browserifyOp));
	let execBundle = () => {
		plugins.util.log(` building ${file}...`);
		return watchifyStream
		.bundle()
		.on("error", plugins.util.log.bind(plugins.util, "Browserify Error"))
		.pipe(source(file))
		.pipe(buffer())
		.pipe(gulp.dest(outDir));
	};

	watchifyStream.on("update", execBundle);
	watchifyStream.on("log", plugins.util.log);
	return execBundle();
};

gulp.task("default", ["watchjs"]);