feat(v2): add CLI option for polling (#2630)

* Add CLI option to polling

Some environments (specifically docker containers) can have issues with file watching for live reloads. [Webpack Dev Server provides a polling alternative](https://webpack.js.org/configuration/watch/#watchoptionspoll) option for this

* Update docusaurus.js

* Update cli.md

Co-authored-by: Yangshun Tay <tay.yang.shun@gmail.com>

packages/docusaurus-types/src/index.d.ts

@@ -60,6 +60,7 @@ export interface StartCLIOptions {
   host: string;
   hotOnly: boolean;
   open: boolean;
+  poll: boolean;
 }
 
 export interface BuildCLIOptions {

packages/docusaurus/bin/docusaurus.js

@@ -85,12 +85,17 @@ cli
     'Do not fallback to page refresh if hot reload fails (default: false)',
   )
   .option('--no-open', 'Do not open page in the browser (default: false)')
-  .action((siteDir = '.', {port, host, hotOnly, open}) => {
+  .option(
+    '--poll',
+    'Use polling rather than watching for reload (default: false)',
+  )
+  .action((siteDir = '.', {port, host, hotOnly, open, poll}) => {
     wrapCommand(start)(path.resolve(siteDir), {
       port,
       host,
       hotOnly,
       open,
+      poll,
     });
   });
 

packages/docusaurus/src/commands/start.ts

@@ -141,6 +141,7 @@ export async function start(
     publicPath: baseUrl,
     watchOptions: {
       ignored: /node_modules/,
+      poll: cliOptions.poll,
     },
     historyApiFallback: {
       rewrites: [{from: /\/*/, to: baseUrl}],

website/docs/cli.md

@@ -48,6 +48,7 @@ Builds and serves a preview of your site locally with [Webpack Dev Server](https
 | `--host` | `localhost` | Specify a host to use. E.g., if you want your server to be accessible externally, you can use `--host 0.0.0.0` |
 | `--hot-only` | `false` | Enables Hot Module Replacement without page refresh as fallback in case of build failures. More information [here](https://webpack.js.org/configuration/dev-server/#devserverhotonly). |
 | `--no-open` | `false` | Do not open automatically the page in the browser. |
+| `--poll` | `false` | Use polling of files rather than watching for live reload as a fallback in environments where watching doesn't work. More information [here](https://webpack.js.org/configuration/watch/#watchoptionspoll). |
 
 :::important