[windows] Support rollup in vanilla template

v2/cmd/wails/internal/commands/initialise/templates/templates/vanilla/frontend/package.tmpl.json

@@ -0,0 +1,27 @@
+{
+  "name": "vanilla",
+  "version": "1.0.0",
+  "description": "Vanilla Wails v2 template",
+  "main": "src/main.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "build": "rollup -c",
+    "dev": "rollup -c -w",
+    "start": "sirv dist"
+  },
+  "author": "{{.AuthorName}}",
+  "license": "ISC",
+  "dependencies": {
+    "@rollup/plugin-commonjs": "^19.0.0",
+    "@rollup/plugin-image": "^2.0.6",
+    "@rollup/plugin-node-resolve": "^13.0.0",
+    "@rollup/plugin-url": "^6.0.0",
+    "@wails/runtime": "^1.3.14",
+    "rollup": "^2.50.4",
+    "rollup-plugin-copy": "^3.4.0",
+    "rollup-plugin-livereload": "^2.0.0",
+    "rollup-plugin-postcss": "^4.0.0",
+    "rollup-plugin-terser": "^7.0.2",
+    "sirv-cli": "^1.0.12"
+  }
+}

v2/cmd/wails/internal/commands/initialise/templates/templates/vanilla/frontend/rollup.config.js

@@ -0,0 +1,103 @@
+import resolve from '@rollup/plugin-node-resolve';
+import commonjs from '@rollup/plugin-commonjs';
+import livereload from 'rollup-plugin-livereload';
+import { terser } from 'rollup-plugin-terser';
+import postcss from 'rollup-plugin-postcss';
+import image from '@rollup/plugin-image';
+import url from '@rollup/plugin-url';
+import copy from 'rollup-plugin-copy';
+
+const production = !process.env.ROLLUP_WATCH;
+
+export default {
+    input: 'src/main.js',
+    output: {
+        sourcemap: true,
+        format: 'iife',
+        name: 'app',
+        file: 'dist/main.js'
+    },
+    onwarn: handleRollupWarning,
+    plugins: [
+
+        image(),
+
+        copy({
+            targets: [
+                { src: 'src/index.html', dest: 'dist' },
+                { src: 'src/main.css', dest: 'dist' },
+            ]
+        }),
+
+        // Embed binary files
+        url({
+            include: ['**/*.woff', '**/*.woff2'],
+            limit: Infinity,
+        }),
+
+        // If you have external dependencies installed from
+        // npm, you'll most likely need these plugins. In
+        // some cases you'll need additional configuration -
+        // consult the documentation for details:
+        // https://github.com/rollup/plugins/tree/master/packages/commonjs
+        resolve({
+            browser: true,
+        }),
+        commonjs(),
+
+        // PostCSS preprocessing
+        postcss({
+            extensions: ['.css', '.scss'],
+            extract: true,
+            minimize: false,
+            use: [
+                ['sass', {
+                    includePaths: [
+                        './src',
+                        './node_modules'
+                    ]
+                }]
+            ],
+        }),
+
+        // In dev mode, call `npm run start` once
+        // the bundle has been generated
+        !production && serve(),
+
+        // Watch the `public` directory and refresh the
+        // browser on changes when not in production
+        !production && livereload('dist'),
+
+        // If we're building for production (npm run build
+        // instead of npm run dev), minify
+        production && terser()
+    ],
+    watch: {
+        clearScreen: false
+    }
+};
+
+function handleRollupWarning(warning) {
+    console.error('ERROR: ' + warning.toString());
+}
+
+function serve() {
+    let server;
+
+    function toExit() {
+        if (server) server.kill(0);
+    }
+
+    return {
+        writeBundle() {
+            if (server) return;
+            server = require('child_process').spawn('npm', ['run', 'start', '--', '--dev'], {
+                stdio: ['ignore', 'inherit', 'inherit'],
+                shell: true
+            });
+
+            process.on('SIGTERM', toExit);
+            process.on('exit', toExit);
+        }
+    };
+}

v2/cmd/wails/internal/commands/initialise/templates/templates/vanilla/frontend/src/main.js

@@ -1,16 +1,21 @@
-// Get input + focus
-let nameElement = document.getElementById("name");
-nameElement.focus();
 
-// Setup the greet function
-window.greet = function () {
+import {ready} from '@wails/runtime';
 
-  // Get name
-  let name = nameElement.value;
+ready( () => {
+  // Get input + focus
+  let nameElement = document.getElementById("name");
+  nameElement.focus();
 
-  // Call Basic.Greet(name)
-  window.backend.main.Basic.Greet(name).then((result) => {
-    // Update result with data back from Basic.Greet()
-    document.getElementById("result").innerText = result;
-  });
-}
+  // Setup the greet function
+  window.greet = function () {
+
+    // Get name
+    let name = nameElement.value;
+
+    // Call Basic.Greet(name)
+    window.backend.main.Basic.Greet(name).then((result) => {
+      // Update result with data back from Basic.Greet()
+      document.getElementById("result").innerText = result;
+    });
+  };
+});

v2/cmd/wails/internal/commands/initialise/templates/templates/vanilla/wails.tmpl.json

@@ -1,7 +1,9 @@
 {
     "name": "{{.ProjectName}}",
     "outputfilename": "{{.BinaryName}}",
-    "html": "frontend/src/index.html",
+    "html": "frontend/dist/index.html",
+    "frontend:build": "npm run build",
+    "frontend:install": "npm ci",
     "author": {
         "name": "{{.AuthorName}}",
         "email": "{{.AuthorEmail}}"