From 852b5e8f13dacb58c9ee4aadd30e27313be9a232 Mon Sep 17 00:00:00 2001
From: Tom Brien <TomBrien@users.noreply.github.com>
Date: Mon, 20 Apr 2020 03:49:43 +0100
Subject: [PATCH] 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  | 1 +
 packages/docusaurus/bin/docusaurus.js     | 7 ++++++-
 packages/docusaurus/src/commands/start.ts | 1 +
 website/docs/cli.md                       | 1 +
 4 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/packages/docusaurus-types/src/index.d.ts b/packages/docusaurus-types/src/index.d.ts
index 2dbdc89b1c..4c2c1cea0f 100644
--- a/packages/docusaurus-types/src/index.d.ts
+++ b/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 {
diff --git a/packages/docusaurus/bin/docusaurus.js b/packages/docusaurus/bin/docusaurus.js
index 6ccc8e20d7..22bac22067 100755
--- a/packages/docusaurus/bin/docusaurus.js
+++ b/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,
     });
   });
 
diff --git a/packages/docusaurus/src/commands/start.ts b/packages/docusaurus/src/commands/start.ts
index 25d5f89df2..04ee554fe1 100644
--- a/packages/docusaurus/src/commands/start.ts
+++ b/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}],
diff --git a/website/docs/cli.md b/website/docs/cli.md
index 36c8f9a283..0495a67f99 100644
--- a/website/docs/cli.md
+++ b/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