Add ES module option.

README.md

@@ -54,6 +54,7 @@ This generator can also be further configured with the following command line fl
         --no-view        use static html instead of view engine
     -c, --css <engine>   add stylesheet <engine> support (less|stylus|compass|sass) (defaults to plain css)
         --git            add .gitignore
+        --es6            generate ES6 code and module-type project (requires Node 14.x or higher)
     -f, --force          force on non-empty directory
     -h, --help           output usage information
 

bin/express-cli.js

@@ -14,6 +14,7 @@ var MODE_0666 = parseInt('0666', 8)
 var MODE_0755 = parseInt('0755', 8)
 var TEMPLATE_DIR = path.join(__dirname, '..', 'templates')
 var VERSION = require('../package').version
+var MIN_ES6_VERSION = 14
 
 // parse args
 var unknown = []
@@ -26,7 +27,7 @@ var args = parseArgs(process.argv.slice(2), {
     H: 'hogan',
     v: 'view'
   },
-  boolean: ['ejs', 'force', 'git', 'hbs', 'help', 'hogan', 'pug', 'version'],
+  boolean: ['ejs', 'es6', 'force', 'git', 'hbs', 'help', 'hogan', 'pug', 'version'],
   default: { css: true, view: true },
   string: ['css', 'view'],
   unknown: function (s) {
@@ -95,17 +96,20 @@ function createApplication (name, dir, options, done) {
     version: '0.0.0',
     private: true,
     scripts: {
-      start: 'node ./bin/www'
+      start: options.es6 ? 'node ./bin/www.mjs' : 'node ./bin/www'
     },
     dependencies: {
       debug: '~2.6.9',
       express: '~4.17.1'
     }
   }
+  if (options.es6) {
+    pkg.type = 'module'
+  }
 
   // JavaScript
-  var app = loadTemplate('js/app.js')
-  var www = loadTemplate('js/www')
+  var app = loadTemplate(options.es6 ? 'mjs/app.js' : 'js/app.js')
+  var www = loadTemplate(options.es6 ? 'mjs/www' : 'js/www')
 
   // App name
   www.locals.name = name
@@ -160,7 +164,9 @@ function createApplication (name, dir, options, done) {
 
   // copy route templates
   mkdir(dir, 'routes')
-  copyTemplateMulti('js/routes', dir + '/routes', '*.js')
+  copyTemplateMulti(
+    options.es6 ? 'mjs/routes' : 'js/routes',
+    dir + '/routes', options.es6 ? '*.mjs' : '*.js')
 
   if (options.view) {
     // Copy view templates
@@ -283,10 +289,10 @@ function createApplication (name, dir, options, done) {
   pkg.dependencies = sortedObject(pkg.dependencies)
 
   // write files
-  write(path.join(dir, 'app.js'), app.render())
+  write(path.join(dir, options.es6 ? 'app.mjs' : 'app.js'), app.render())
   write(path.join(dir, 'package.json'), JSON.stringify(pkg, null, 2) + '\n')
   mkdir(dir, 'bin')
-  write(path.join(dir, 'bin/www'), www.render(), MODE_0755)
+  write(path.join(dir, options.es6 ? 'bin/www.mjs' : 'bin/www'), www.render(), MODE_0755)
 
   var prompt = launchedFromCmd() ? '>' : '$'
 
@@ -433,6 +439,10 @@ function main (options, done) {
     usage()
     error('option `-v, --view <engine>\' argument missing')
     done(1)
+  } else if (options.es6 && process.versions.node.split('.')[0] < MIN_ES6_VERSION) {
+    usage()
+    error('option `--es6\' requires Node version ' + MIN_ES6_VERSION + '.x or higher')
+    done(1)
   } else {
     // Path
     var destinationPath = options._[0] || '.'
@@ -521,6 +531,7 @@ function usage () {
   console.log('        --no-view        use static html instead of view engine')
   console.log('    -c, --css <engine>   add stylesheet <engine> support (less|stylus|compass|sass) (defaults to plain css)')
   console.log('        --git            add .gitignore')
+  console.log('        --es6            generate ES6 code and module-type project (requires Node 14.x or higher)')
   console.log('    -f, --force          force on non-empty directory')
   console.log('    --version            output the version number')
   console.log('    -h, --help           output usage information')

templates/mjs/app.js.ejs

@@ -0,0 +1,54 @@
+<% if (view) { -%>
+import createError from 'http-errors';
+<% } -%>
+import express from 'express';
+import path from 'path';
+import { fileURLToPath } from 'url';
+<% Object.keys(modules).sort().forEach(function (variable) { -%>
+import <%- variable %> from '<%- modules[variable] %>';
+<% }); -%>
+
+<% Object.keys(localModules).sort().forEach(function (variable) { -%>
+import <%- variable %> from '<%- localModules[variable] %>.mjs';
+<% }); -%>
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+const app = express();
+
+<% if (view) { -%>
+// view engine setup
+<% if (view.render) { -%>
+app.engine('<%- view.engine %>', <%- view.render %>);
+<% } -%>
+app.set('views', path.join(__dirname, 'views'));
+app.set('view engine', '<%- view.engine %>');
+
+<% } -%>
+<% uses.forEach(function (use) { -%>
+app.use(<%- use %>);
+<% }); -%>
+
+<% mounts.forEach(function (mount) { -%>
+app.use(<%= mount.path %>, <%- mount.code %>);
+<% }); -%>
+
+<% if (view) { -%>
+// catch 404 and forward to error handler
+app.use((req, res, next) => {
+  next(createError(404));
+});
+
+// error handler
+app.use((err, req, res, next) => {
+  // set locals, only providing error in development
+  res.locals.message = err.message;
+  res.locals.error = req.app.get('env') === 'development' ? err : {};
+
+  // render the error page
+  res.status(err.status || 500);
+  res.render('error');
+});
+
+<% } -%>
+export default app;

templates/mjs/routes/index.mjs

@@ -0,0 +1,9 @@
+import express from 'express';
+const router = express.Router();
+
+/* GET home page. */
+router.get('/', (req, res, next) => {
+  res.render('index', { title: 'Express' });
+});
+
+export default router;

templates/mjs/routes/users.mjs

@@ -0,0 +1,9 @@
+import express from 'express';
+const router = express.Router();
+
+/* GET users listing. */
+router.get('/', (req, res, next) => {
+  res.send('respond with a resource');
+});
+
+export default router;

templates/mjs/www.ejs

@@ -0,0 +1,91 @@
+#!/usr/bin/env node
+
+/**
+ * Module dependencies.
+ */
+
+import app from '../app.mjs';
+import http from 'http';
+import debugFunction from 'debug';
+const debug = debugFunction('<%- name %>:server');
+
+/**
+ * Get port from environment and store in Express.
+ */
+
+const port = normalizePort(process.env.PORT || '3000');
+app.set('port', port);
+
+/**
+ * Create HTTP server.
+ */
+
+const server = http.createServer(app);
+
+/**
+ * Listen on provided port, on all network interfaces.
+ */
+
+server.listen(port);
+server.on('error', onError);
+server.on('listening', onListening);
+
+/**
+ * Normalize a port into a number, string, or false.
+ */
+
+function normalizePort(val) {
+  const port = parseInt(val, 10);
+
+  if (isNaN(port)) {
+    // named pipe
+    return val;
+  }
+
+  if (port >= 0) {
+    // port number
+    return port;
+  }
+
+  return false;
+}
+
+/**
+ * Event listener for HTTP server "error" event.
+ */
+
+function onError(error) {
+  if (error.syscall !== 'listen') {
+    throw error;
+  }
+
+  const bind = typeof port === 'string'
+    ? 'Pipe ' + port
+    : 'Port ' + port;
+
+  // handle specific listen errors with friendly messages
+  switch (error.code) {
+    case 'EACCES':
+      console.error(bind + ' requires elevated privileges');
+      process.exit(1);
+      break;
+    case 'EADDRINUSE':
+      console.error(bind + ' is already in use');
+      process.exit(1);
+      break;
+    default:
+      throw error;
+  }
+}
+
+/**
+ * Event listener for HTTP server "listening" event.
+ */
+
+function onListening() {
+  const addr = server.address();
+  const bind = typeof addr === 'string'
+    ? 'pipe ' + addr
+    : 'port ' + addr.port;
+  debug('Listening on ' + bind);
+}