feat: validate equal page names for posts and data

Author: ChristianBeilschmidt

astro.config.mjs

@@ -3,6 +3,7 @@ import tailwindcss from '@tailwindcss/vite';
 import pagefind from 'astro-pagefind';
 import icon from 'astro-icon';
 import cookieconsent from '@jop-software/astro-cookieconsent';
+import equalPageNameValidator from './src/integrations/equal-page-name-validator';
 
 // https://astro.build/config
 export default defineConfig({
@@ -14,6 +15,8 @@ export default defineConfig({
     },
 
     integrations: [
+        equalPageNameValidator('posts/', 'en/posts/'),
+        equalPageNameValidator('data/', 'en/data/'),
         icon({
             iconDir: './src/images/icons',
         }),

src/i18n/utils.ts

@@ -1,6 +1,5 @@
 import {getRelativeLocaleUrl} from 'astro:i18n';
 import {translations, defaultLang, pages} from './translations';
-import {redirectSearchParam} from '../pages/404.astro';
 
 // export function getLangFromUrl(url: URL) {
 //     const [, lang] = url.pathname.split('/');
@@ -61,7 +60,7 @@ export function pageInOtherLocale(lang: LocaleString, currentPath: string) {
     if (path.startsWith('/en/')) {
         path = path.substring(4); // remove /en/
     }
-    return getRelativeLocaleUrl(lang, path) + '?' + redirectSearchParam;
+    return getRelativeLocaleUrl(lang, path);
 }
 
 function localePagePrefix(lang: LocaleString): string {

src/integrations/equal-page-name-validator.ts

@@ -0,0 +1,64 @@
+import type {AstroIntegration} from 'astro';
+
+/**
+ * Validates that for every page under pathA there is a corresponding page under pathB and vice versa.
+ */
+export default function equalPageNameValidator(pathA: string, pathB: string): AstroIntegration {
+    if (!pathA || !pathB) {
+        throw new Error('Both paths must be provided');
+    }
+    if (pathA === pathB) {
+        throw new Error('The two paths must be different');
+    }
+
+    // Canonicalize paths to always end with a slash
+    if (!pathA.endsWith('/')) {
+        pathA += '/';
+    }
+    if (!pathB.endsWith('/')) {
+        pathB += '/';
+    }
+
+    return {
+        name: 'equal-page-name-validator',
+        hooks: {
+            'astro:build:done': ({logger, dir, pages}) => {
+                logger.info(`Validating equal page names between ${pathA} and ${pathB}…`);
+
+                const aPages = new Set<string>();
+                const bPages = new Set<string>();
+
+                for (const page of pages) {
+                    if (page.pathname.startsWith(pathA)) {
+                        aPages.add(page.pathname.substring(pathA.length));
+                    } else if (page.pathname.startsWith(pathB)) {
+                        bPages.add(page.pathname.substring(pathB.length));
+                    }
+                }
+
+                if (aPages.size === 0) {
+                    logger.warn(`No pages found for path A: ${pathA}`);
+                }
+                if (bPages.size === 0) {
+                    logger.warn(`No pages found for path B: ${pathB}`);
+                }
+
+                const difference = aPages.difference(bPages);
+                const reverseDifference = bPages.difference(aPages);
+                const totalDifferences = difference.size + reverseDifference.size;
+                if (totalDifferences > 0) {
+                    logger.error(`Found ${totalDifferences} page(s) that do not have a counterpart:`);
+                    for (const page of difference) {
+                        logger.error(` - ${pathA}${page}`);
+                    }
+                    for (const page of reverseDifference) {
+                        logger.error(` - ${pathB}${page}`);
+                    }
+                    throw new Error(`Validation failed: ${totalDifferences} page(s) do not have a counterpart.`);
+                }
+
+                logger.info(`All ${aPages.size} page(s) in ${pathA} have a counterpart in ${pathB} and vice versa.`);
+            },
+        },
+    };
+}

src/pages/404.astro

@@ -8,8 +8,6 @@ import {Icon} from 'astro-icon/components';
 const currentLang = currentLanguage(Astro.currentLocale);
 const t = useTranslations(currentLang);
 const homeLink = getRelativeLocaleUrl(currentLang, '/');
-
-export const redirectSearchParam = 'redirect-if-not-found';
 ---
 
 <Layout title={t('404.title')} description={t('404.description')}>
@@ -19,21 +17,3 @@ export const redirectSearchParam = 'redirect-if-not-found';
         <Icon name="404" class="text-main-lightgreen m-auto text-[25vw]" />
     </Section>
 </Layout>
-
-<redirect-optionally data-home-link={homeLink} data-search-param={redirectSearchParam}></redirect-optionally>
-
-<script>
-    class Redirector extends HTMLElement {
-        connectedCallback() {
-            const searchParams = new URLSearchParams(window.location.search);
-            const homeLink = this.dataset.homeLink;
-            const redirectSearchParam = this.dataset.searchParam ?? '';
-
-            if (homeLink && searchParams.has(redirectSearchParam)) {
-                window.location.href = homeLink;
-            }
-        }
-    }
-
-    customElements.define('redirect-optionally', Redirector);
-</script>