Implement file attachments frontend

Signed-off-by: Julius Härtl <jus@bitgrid.net>

js/filters/bytesFilter.js

@@ -0,0 +1,37 @@
+/*
+ * @copyright Copyright (c) 2018 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+import app from '../app/App.js';
+
+app.filter('bytes', function () {
+	return function (bytes, precision) {
+		if (isNaN(parseFloat(bytes, 10)) || !isFinite(bytes)) {
+			return '-';
+		}
+		if (precision === undefined) {
+			precision = 2;
+		}
+		var units = ['bytes', 'KB', 'MB', 'GB', 'TB', 'PB'],
+			number = Math.floor(Math.log(bytes) / Math.log(1024));
+		return (bytes / Math.pow(1024, Math.floor(number))).toFixed(precision) +  ' ' + units[number];
+	};
+});