From 7efa67af84b60b14724517e634673460bfcef8a1 Mon Sep 17 00:00:00 2001
From: Kristóf Marussy <kristof@marussy.com>
Date: Thu, 21 Mar 2024 12:35:52 +0100
Subject: Also compress Docusaurus-generated files

Run the compression manually for files that are not generated by Webpack.

We must take over the @docusaurus/plugin-sitemap plugin to make sure we run
after it has generated sitemap.xml. Docusaurus runs all plugin post-build
actions in parallel with Promise.all, so the only way to do this is to invoke
the post-build action in our own one.
---
 src/plugins/compressionPlugin.ts | 53 +++++++++++++++++++++++++++++++---------
 1 file changed, 41 insertions(+), 12 deletions(-)

(limited to 'src')

diff --git a/src/plugins/compressionPlugin.ts b/src/plugins/compressionPlugin.ts
index b1cff6a..8b347cf 100644
--- a/src/plugins/compressionPlugin.ts
+++ b/src/plugins/compressionPlugin.ts
@@ -4,14 +4,35 @@
  * SPDX-License-Identifier: MIT
  */
 
-import zlib, { type BrotliOptions } from 'node:zlib';
+import { readFile, writeFile } from 'node:fs/promises';
+import path from 'node:path';
+import { promisify } from 'node:util';
+import zlib, { type BrotliOptions, type ZlibOptions } from 'node:zlib';
 
-import type { Plugin } from '@docusaurus/types';
+import pluginSitemap, { type PluginOptions } from '@docusaurus/plugin-sitemap';
+import type { LoadContext, Plugin } from '@docusaurus/types';
+import { Globby } from '@docusaurus/utils';
 import CompressionPlugin from 'compression-webpack-plugin';
 
-const test = /\.(js|css|html|svg|txt)$/;
+const gzipOptions = {
+  level: 9,
+} satisfies ZlibOptions;
+const brotliOptions = {
+  params: {
+    [zlib.constants.BROTLI_PARAM_QUALITY]: 11,
+  },
+};
+const test = /\.(js|css|svg|txt)$/;
+const paths = ['**/*.html', 'robots.txt', 'sitemap.xml'];
 
-export default function compressionPlugin(): Plugin {
+const gzip = promisify(zlib.gzip);
+const brotliCompress = promisify(zlib.brotliCompress);
+
+export default function compressionPlugin(
+  context: LoadContext,
+  options: PluginOptions,
+): Plugin<void> {
+  const sitemap = pluginSitemap(context, options);
   return {
     name: 'marussy-compression-plugin',
     configureWebpack: (_config, isServer) =>
@@ -22,21 +43,29 @@ export default function compressionPlugin(): Plugin {
               new CompressionPlugin({
                 test,
                 filename: '[path][base].gz',
-                compressionOptions: {
-                  level: 9,
-                },
+                compressionOptions: gzipOptions,
               }),
               new CompressionPlugin<BrotliOptions>({
                 test,
                 filename: '[path][base].br',
                 algorithm: 'brotliCompress',
-                compressionOptions: {
-                  params: {
-                    [zlib.constants.BROTLI_PARAM_QUALITY]: 11,
-                  },
-                },
+                compressionOptions: brotliOptions,
               }),
             ],
           },
+    async postBuild(props) {
+      await sitemap?.postBuild(props);
+      const files = await Globby(paths.map((s) => path.join(props.outDir, s)));
+      for (const file of files) {
+        console.log(file);
+        const contents = await readFile(file);
+        const gzipContents = await gzip(contents, gzipOptions);
+        await writeFile(`${file}.gz`, gzipContents);
+        const brotliContents = await brotliCompress(contents, brotliOptions);
+        await writeFile(`${file}.br`, brotliContents);
+      }
+    },
   };
 }
+
+export { validateOptions } from '@docusaurus/plugin-sitemap';
-- 
cgit v1.2.3-70-g09d2