Minify modules in a batch

src/meta/js.js

@@ -88,44 +88,56 @@ module.exports = function (Meta) {
 		},
 	};
 
+	function copyFile(source, target, cb) {
+		var called = false;
+
+		var rd = fs.createReadStream(source);
+		rd.on('error', done);
+
+		var wr = fs.createWriteStream(target);
+		wr.on('error', done);
+		wr.on('close', function () {
+			done();
+		});
+		rd.pipe(wr);
+
+		function done(err) {
+			if (!called) {
+				cb(err);
+				called = true;
+			}
+		}
+	}
+
 	function minifyModules(modules, fork, callback) {
-		// for it to never fork
-		// otherwise it spawns way too many processes
-		// maybe eventually we can pool modules
-		// and pass the pools to the minifer
-		// to reduce the total number of threads
-		fork = false;
+		async.eachLimit(modules, 1000, function (mod, next) {
+			mkdirp(path.dirname(mod.destPath), next);
+		}, function (err) {
+			if (err) {
+				return callback(err);
+			}
 
-		async.eachLimit(modules, 500, function (mod, next) {
-			var srcPath = mod.srcPath;
-			var destPath = mod.destPath;
-
-			async.parallel({
-				dirped: function (cb) {
-					mkdirp(path.dirname(destPath), cb);
-				},
-				minified: function (cb) {
-					fs.readFile(srcPath, function (err, buffer) {
-						if (err) {
-							return cb(err);
-						}
-
-						if (srcPath.endsWith('.min.js') || path.dirname(srcPath).endsWith('min')) {
-							return cb(null, { code: buffer.toString() });
-						}
-
-						minifier.js.minify(buffer.toString(), fork, cb);
-					});
-				},
-			}, function (err, results) {
-				if (err) {
-					return next(err);
+			var filtered = modules.reduce(function (prev, mod) {
+				if (mod.srcPath.endsWith('.min.js') || path.dirname(mod.srcPath).endsWith('min')) {
+					prev.skip.push(mod);
+				} else {
+					prev.minify.push(mod);
 				}
 
-				var minified = results.minified;
-				fs.writeFile(destPath, minified.code, next);
-			});
-		}, callback);
+				return prev;
+			}, { minify: [], skip: [] });
+
+			async.parallel([
+				function (cb) {
+					minifier.js.minifyBatch(filtered.minify, fork, cb);
+				},
+				function (cb) {
+					async.eachLimit(filtered.skip, 500, function (mod, next) {
+						copyFile(mod.srcPath, mod.destPath, next);
+					}, cb);
+				},
+			], callback);
+		});
 	}
 
 	function linkModules(callback) {