feat: add preview update channel

1 files changed, 76 insertions, 4 deletions

diff --git a/website/scripts/prepare-docs.mjs b/website/scripts/prepare-docs.mjs
index c6fefaf7..19201a18 100644
--- a/website/scripts/prepare-docs.mjs
+++ b/website/scripts/prepare-docs.mjs
@@ -1,12 +1,23 @@
-import { cp, mkdir, rm } from 'node:fs/promises';
-import { dirname, resolve } from 'node:path';
+import { cp, mkdir, readdir, readFile, rm, writeFile } from 'node:fs/promises';
+import { dirname, join, relative, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
+import process from 'node:process';
 
 const websiteDir = dirname(fileURLToPath(import.meta.url));
 const repoRoot = resolve(websiteDir, '../..');
 const publicDir = resolve(repoRoot, 'website/public');
+const stableDocsDir = resolve(repoRoot, 'website/src/content/docs');
+const previewDocsSourceDir = resolve(repoRoot, 'docs/next/website/src/content/docs');
+const previewDocsDir = resolve(stableDocsDir, 'preview');
 
-await preparePublicAssets();
+if (process.argv[2] === '--rewrite-preview-doc-fixture') {
+  const chunks = [];
+  for await (const chunk of process.stdin) chunks.push(chunk);
+  process.stdout.write(rewritePreviewDocContent(Buffer.concat(chunks).toString('utf8')));
+} else {
+  await preparePublicAssets();
+  await preparePreviewDocs();
+}
 
 async function preparePublicAssets() {
   await rm(publicDir, { recursive: true, force: true });
@@ -15,11 +26,17 @@ async function preparePublicAssets() {
   for (const file of [
     'install.sh',
     'latest.json',
+    'preview.json',
     'robots.txt',
     '_headers',
     '_redirects',
   ]) {
-    await cp(resolve(repoRoot, 'website', file), resolve(publicDir, file));
+    const source = resolve(repoRoot, 'website', file);
+    try {
+      await cp(source, resolve(publicDir, file));
+    } catch (error) {
+      if (file !== 'preview.json' || error.code !== 'ENOENT') throw error;
+    }
   }
 
   for (const directory of ['assets', 'css']) {
@@ -28,3 +45,58 @@ async function preparePublicAssets() {
     });
   }
 }
+
+async function preparePreviewDocs() {
+  await rm(previewDocsDir, { recursive: true, force: true });
+  await copyPreviewDocs(previewDocsSourceDir, previewDocsDir);
+}
+
+async function copyPreviewDocs(sourceDir, destinationDir) {
+  await mkdir(destinationDir, { recursive: true });
+  for (const entry of await readdir(sourceDir, { withFileTypes: true })) {
+    const source = join(sourceDir, entry.name);
+    const destination = join(destinationDir, entry.name);
+    if (entry.isDirectory()) {
+      await copyPreviewDocs(source, destination);
+      continue;
+    }
+    if (!entry.isFile()) continue;
+
+    const content = await readFile(source, 'utf8');
+    const relativePath = relative(previewDocsSourceDir, source);
+    await writeFile(destination, rewritePreviewDocContent(content, relativePath), 'utf8');
+  }
+}
+
+export function rewritePreviewDocContent(content, relativePath = '') {
+  const rewritten = content
+    .replaceAll('/docs/', '/docs/preview/')
+    .replaceAll('../../../public/', '../../../../public/');
+  return insertPreviewNotice(rewritten, relativePath);
+}
+
+function insertPreviewNotice(content, relativePath) {
+  const notice = [
+    '> Preview docs describe unreleased preview builds. Stable docs remain at [/docs/](/docs/).',
+    '',
+    '',
+  ].join('\n');
+  const indexPrefix =
+    relativePath === 'index.mdx'
+      ? content.replace('title: Herdr documentation', 'title: Herdr preview documentation')
+      : content;
+  const frontmatter = indexPrefix.match(/^---\n[\s\S]*?\n---\n/);
+  if (!frontmatter) {
+    return insertNoticeAfterImports(indexPrefix, notice);
+  }
+  const body = indexPrefix.slice(frontmatter[0].length);
+  return `${frontmatter[0]}\n${insertNoticeAfterImports(body, notice)}`;
+}
+
+function insertNoticeAfterImports(content, notice) {
+  const imports = content.match(/^(\s*import .+?;\n)+\s*/);
+  if (!imports) {
+    return `${notice}${content}`;
+  }
+  return `${imports[0]}${notice}${content.slice(imports[0].length)}`;
+}