GUI extension Yeoman generator

Change-Id: If6b3fae44e4ee8a7bde36600cdc71d54d49fbf6e
diff --git a/generator-xos-gui-extension/generators/templates/gulp_tasks/webpack.js b/generator-xos-gui-extension/generators/templates/gulp_tasks/webpack.js
new file mode 100755
index 0000000..ccb64c0
--- /dev/null
+++ b/generator-xos-gui-extension/generators/templates/gulp_tasks/webpack.js
@@ -0,0 +1,67 @@
+
+/*
+ * Copyright 2017-present Open Networking Foundation
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+
+ * http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+const gulp = require('gulp');
+const gutil = require('gulp-util');
+
+const webpack = require('webpack');
+const webpackConf = require('../conf/webpack.conf');
+const webpackDistConf = require('../conf/webpack-dist.conf');
+const gulpConf = require('../conf/gulp.conf');
+const browsersync = require('browser-sync');
+
+gulp.task('webpack:dev', done => {
+  webpackWrapper(false, webpackConf, done);
+});
+
+gulp.task('webpack:watch', done => {
+  webpackWrapper(true, webpackConf, done);
+});
+
+gulp.task('webpack:dist', done => {
+  process.env.NODE_ENV = 'production';
+  webpackWrapper(false, webpackDistConf, done);
+});
+
+function webpackWrapper(watch, conf, done) {
+  const webpackBundler = webpack(conf);
+
+  const webpackChangeHandler = (err, stats) => {
+    if (err) {
+      gulpConf.errorHandler('Webpack')(err);
+    }
+    gutil.log(stats.toString({
+      colors: true,
+      chunks: false,
+      hash: false,
+      version: false
+    }));
+    if (done) {
+      done();
+      done = null;
+    } else {
+      browsersync.reload();
+    }
+  };
+
+  if (watch) {
+    webpackBundler.watch(200, webpackChangeHandler);
+  } else {
+    webpackBundler.run(webpackChangeHandler);
+  }
+}