feature: preview links in CMS

.env.example

@@ -1,3 +1,4 @@
 DATOCMS_READONLY_API_TOKEN="<Read-only API token>"
 DATOCMS_API_TOKEN="<Full-access API token>"
+DATOCMS_PREVIEW_API_TOKEN="<Custom API token for preview>"
 HEAD_START_PREVIEW_SECRET=""

config/datocms/migrations/1734806654_previewLinks.ts

@@ -0,0 +1,64 @@
+import { Client } from '@datocms/cli/lib/cma-client-node';
+
+export default async function (client: Client) {
+  console.log('Manage upload filters');
+
+  console.log('Install plugin "Model Deployment Links"');
+  await client.plugins.create({
+    id: 'MKba9NT5QBKZaeI4HcERwA',
+    package_name: 'datocms-plugin-model-deployment-links',
+  });
+  await client.plugins.update('MKba9NT5QBKZaeI4HcERwA', {
+    parameters: { datoApiToken: process.env.DATOCMS_PREVIEW_API_TOKEN },
+  });
+
+  console.log('Creating new fields/fieldsets');
+
+  console.log(
+    'Create JSON field "Preview" (`preview`) in model "\uD83D\uDCD1 Page" (`page`)'
+  );
+  await client.fields.create('LjXdkuCdQxCFT4hv8_ayew', {
+    id: 'XF2LuFVWSrmu7Lle8xlhTg',
+    label: 'Preview',
+    field_type: 'json',
+    api_key: 'preview',
+    localized: true,
+    appearance: {
+      addons: [],
+      editor: 'MKba9NT5QBKZaeI4HcERwA',
+      parameters: { urlPattern: '/{ locale }/{ slug }/' },
+    },
+  });
+
+  console.log(
+    'Create JSON field "Preview" (`preview`) in model "\uD83C\uDFE0 Home" (`home_page`)'
+  );
+  await client.fields.create('X_tZn3TxQY28ltSyjZUGHQ', {
+    id: 'YPXZOMoWRdKTHLUkN9ytfw',
+    label: 'Preview',
+    field_type: 'json',
+    api_key: 'preview',
+    localized: true,
+    appearance: {
+      addons: [],
+      editor: 'MKba9NT5QBKZaeI4HcERwA',
+      parameters: { urlPattern: '/{ locale }/' },
+    },
+  });
+
+  console.log(
+    'Create JSON field "Preview" (`preview`) in model "\uD83E\uDD37 Not found" (`not_found_page`)'
+  );
+  await client.fields.create('d_AvMVoMSqmNbMqx-NdqIw', {
+    id: 'O_DCfpaDSzq1MX4DaRlMpQ',
+    label: 'Preview',
+    field_type: 'json',
+    api_key: 'preview',
+    localized: true,
+    appearance: {
+      addons: [],
+      editor: 'MKba9NT5QBKZaeI4HcERwA',
+      parameters: { urlPattern: '/{ locale }/404' },
+    },
+  });
+}

datocms-environment.ts

@@ -3,5 +3,5 @@
  * @see docs/getting-started.md on how to use this file
  * @see docs/decision-log/2023-10-24-datocms-env-file.md on why file is preferred over env vars
  */
-export const datocmsEnvironment = 'action-block';
+export const datocmsEnvironment = 'preview-links';
 export const datocmsBuildTriggerId = '30535';

src/pages/404.astro

@@ -1,9 +1,6 @@
 ---
 import type { SiteLocale } from '@lib/i18n/types';
-import type {
-  NotFoundPageQuery,
-  NotFoundPageRecord,
-} from '@lib/datocms/types';
+import type { NotFoundPageQuery, NotFoundPageRecord } from '@lib/datocms/types';
 import { datocmsRequest } from '@lib/datocms';
 import { noIndexTag, titleTag } from '@lib/seo';
 import Layout from '@layouts/Default.astro';
@@ -15,14 +12,16 @@ export const prerender = false;
 
 Astro.response.status = 404;
 
-const { locale } = Astro.params as { locale: SiteLocale };
+const localeFromPath = Astro.params.locale as SiteLocale;
+const localeFromQuery = Astro.url.searchParams.get('locale') as SiteLocale;
+const locale = localeFromQuery || localeFromPath;
 const { page } = (await datocmsRequest<NotFoundPageQuery>({
   query,
   variables: { locale },
 })) as { page: NotFoundPageRecord };
 ---
 
 <Layout pageUrls={[]} seoMetaTags={[noIndexTag, titleTag(page.title)]}>
-  <h1>{page.title} {Astro.params.locale}</h1>
+  <h1>{page.title}</h1>
   <Blocks blocks={page.bodyBlocks as AnyBlock[]} />
 </Layout>

src/pages/[locale]/[...path]/index.astro

@@ -53,19 +53,30 @@ type Params = {
 
 const { locale, path } = Astro.params as Params;
 const variables = { locale, slug: getPageSlugFromPath(path) };
-const { page } = (await datocmsRequest<PageQuery>({ query, variables })) as {
-  page: NonNullable<PageQuery['page']>; // Only NonNullable when statically generated. Handle as a 404 when this is a server route!
-};
-const breadcrumbs = [...getParentPages(page), page].map((page) =>
+const { page } = await datocmsRequest<PageQuery>({ query, variables });
+
+if (!page) {
+  return Astro.rewrite(`/404/?locale=${locale}`);
+}
+
+const canonicalUrl = getPageHref({ locale, record: page });
+if (Astro.url.pathname !== canonicalUrl) {
+  return Astro.redirect(canonicalUrl);
+}
+
+const breadcrumbs = [...getParentPages(page), page].map((record) =>
   formatBreadcrumb({
-    text: page.title,
-    href: getPageHref({ locale, record: page }),
+    text: record.title,
+    href: getPageHref({ locale, record }),
   })
 );
-const pageUrls = (page._allSlugLocales || []).map(({ locale }) => ({
-  locale: locale as SiteLocale,
-  pathname: getPageHref({ locale: locale as SiteLocale, record: page }),
-})) as PageUrl[];
+
+const pageLocales = (page._allSlugLocales?.map(({ locale }) => locale) ??
+  []) as SiteLocale[];
+const pageUrls = pageLocales.map((locale) => ({
+  locale,
+  pathname: getPageHref({ locale, record: page }),
+})) satisfies PageUrl[];
 ---
 
 <Layout

src/pages/api/reroute/_page.query.graphql

@@ -0,0 +1,7 @@
+#import '@lib/routing/PageRoute.fragment.graphql'
+
+query ReroutePage($locale: SiteLocale!, $slug: String!) {
+  page(locale: $locale, filter: { slug: { eq: $slug } }) {
+    ...PageRoute
+  }
+}

src/pages/api/reroute/page.ts

@@ -0,0 +1,38 @@
+import type { APIRoute } from 'astro';
+import { datocmsRequest } from '@lib/datocms';
+import type { ReroutePageQuery, SiteLocale } from '@lib/datocms/types';
+import { getPageHref } from '@lib/routing';
+import query from './_page.query.graphql';
+
+export const prerender = false;
+
+const jsonResponse = (data: object, status: number = 200) => {
+  return new Response(JSON.stringify(data), {
+    status,
+    headers: {
+      'Content-Type': 'application/json',
+    },
+  });
+};
+
+export const GET: APIRoute = async ({ request }) => {
+  const locale = new URL(request.url).searchParams.get('locale') as SiteLocale;
+  if (!locale) {
+    return jsonResponse({ error: 'Missing \'locale\' parameter' }, 400);
+  }
+
+  const slug = new URL(request.url).searchParams.get('slug');
+  if (!slug) {
+    return jsonResponse({ error: 'Missing \'slug\' parameter' }, 400);
+  }
+
+  const { page } = (await datocmsRequest<ReroutePageQuery>({ query, variables: { slug, locale } }));
+  if (!page) {
+    return jsonResponse({ error: 'Page not found' }, 404);
+  }
+
+  return new Response('',{
+    status: 307,
+    headers: { 'Location': getPageHref({ locale, record: page }) },
+  });
+};