Add 'gzip' plugin

CHANGELOG.md

@@ -10,6 +10,7 @@ Go to the `v1` branch to see the changelog of Lume 1.
 - New plugin: `check_urls` to detect broken links [#675].
 - New plugin: `icons` to load automatically icons from popular icon catalogs.
 - New plugin: `google_fonts` to download and self-host automatically fonts from Google Fonts.
+- New plugin: `gzip` to compress files. [#680]
 
 ### Fixed
 - Nav plugin: Breadcrumb with urls with CJK characters.
@@ -564,6 +565,7 @@ Go to the `v1` branch to see the changelog of Lume 1.
 [#677]: https://github.com/lumeland/lume/issues/677
 [#678]: https://github.com/lumeland/lume/issues/678
 [#679]: https://github.com/lumeland/lume/issues/679
+[#680]: https://github.com/lumeland/lume/issues/680
 
 [Unreleased]: https://github.com/lumeland/lume/compare/v2.3.3...HEAD
 [2.3.3]: https://github.com/lumeland/lume/compare/v2.3.2...v2.3.3

core/utils/lume_config.ts

@@ -13,6 +13,7 @@ export const pluginNames = [
   "fff",
   "filter_pages",
   "google_fonts",
+  "gzip",
   "inline",
   "jsx",
   "jsx_preact",

deps/streams.ts

@@ -0,0 +1 @@
+export * from "jsr:@std/[email protected]";

plugins/gzip.ts

@@ -0,0 +1,53 @@
+import { merge } from "../core/utils/object.ts";
+import { concurrent } from "../core/utils/concurrent.ts";
+import { Page } from "../core/file.ts";
+import { toArrayBuffer } from "../deps/streams.ts";
+
+import type { Extensions } from "../core/utils/path.ts";
+import type Site from "../core/site.ts";
+
+export interface Options {
+  /** The list of extensions this plugin applies to */
+  extensions?: Extensions;
+}
+
+// Default options
+export const defaults: Options = {
+  extensions: [".html", ".css", ".js", ".mjs", ".svg", ".json", ".xml", ".txt"],
+};
+
+/**
+ * A plugin to compress files with gzip
+ */
+export function gzip(userOptions?: Options) {
+  const options = merge(defaults, userOptions);
+
+  return (site: Site) => {
+    const textEncoder = new TextEncoder();
+
+    site.process(
+      options.extensions,
+      (pages, allPages) =>
+        concurrent(pages, async (page: Page) => {
+          const content = page.content!;
+          const contentStream = ReadableStream.from([
+            typeof content === "string" ? textEncoder.encode(content) : content,
+          ]);
+
+          const compressedStream = contentStream.pipeThrough(
+            new CompressionStream("gzip"),
+          );
+          const compressedArrayBuffer = await toArrayBuffer(compressedStream);
+          const compressedContent = new Uint8Array(compressedArrayBuffer);
+
+          const compressedPage = Page.create({
+            url: page.outputPath + ".gz",
+            content: compressedContent,
+          });
+          allPages.push(compressedPage);
+        }),
+    );
+  };
+}
+
+export default gzip;