fix: handle revalidate on post delete (#94)

Co-authored-by: Cody Olsen <81981+stipsan@users.noreply.github.com>

pages/api/revalidate.ts

@@ -42,14 +42,13 @@ export default async function revalidate(
       return res.status(401).send(message)
     }
 
-    const { _id, _type } = body
-    if (typeof _id !== 'string' || !_id) {
+    if (typeof body._id !== 'string' || !body._id) {
       const invalidId = 'Invalid _id'
       console.error(invalidId, { body })
       return res.status(400).send(invalidId)
     }
 
-    const staleRoutes = await queryStaleRoutes({ _id, _type })
+    const staleRoutes = await queryStaleRoutes(body as any)
     await Promise.all(staleRoutes.map((route) => res.revalidate(route)))
 
     const updatedRoutes = `Updated routes: ${staleRoutes.join(', ')}`
@@ -64,10 +63,33 @@ export default async function revalidate(
 type StaleRoute = '/' | `/posts/${string}`
 
 async function queryStaleRoutes(
-  body: Pick<ParseBody['body'], '_type' | '_id'>
+  body: Pick<ParseBody['body'], '_type' | '_id' | 'date' | 'slug'>
 ): Promise<StaleRoute[]> {
   const client = createClient({ projectId, dataset, apiVersion, useCdn: false })
 
+  // Handle possible deletions
+  if (body._type === 'post') {
+    const exists = await client.fetch(groq`*[_id == $id][0]`, { id: body._id })
+    if (!exists) {
+      let staleRoutes: StaleRoute[] = ['/']
+      if ((body.slug as any)?.current) {
+        staleRoutes.push(`/posts/${(body.slug as any).current}`)
+      }
+      // Assume that the post document was deleted. Query the datetime used to sort "More stories" to determine if the post was in the list.
+      const moreStories = await client.fetch(
+        groq`count(
+          *[_type == "post"] | order(date desc, _updatedAt desc) [0...3] [dateTime(date) > dateTime($date)]
+        )`,
+        { date: body.date }
+      )
+      // If there's less than 3 posts with a newer date, we need to revalidate everything
+      if (moreStories < 3) {
+        return [...new Set([...(await queryAllRoutes(client)), ...staleRoutes])]
+      }
+      return staleRoutes
+    }
+  }
+
   switch (body._type) {
     case 'author':
       return await queryStaleAuthorRoutes(client, body._id)

schemas/author.ts

@@ -1,24 +1,24 @@
 import { UserIcon } from '@sanity/icons'
-import { defineType } from 'sanity'
+import { defineField, defineType } from 'sanity'
 
 export default defineType({
   name: 'author',
   title: 'Author',
   icon: UserIcon,
   type: 'document',
   fields: [
-    {
+    defineField({
       name: 'name',
       title: 'Name',
       type: 'string',
       validation: (Rule) => Rule.required(),
-    },
-    {
+    }),
+    defineField({
       name: 'picture',
       title: 'Picture',
       type: 'image',
       options: { hotspot: true },
       validation: (Rule) => Rule.required(),
-    },
+    }),
   ],
 })

schemas/post.ts

@@ -1,5 +1,6 @@
 import { BookIcon } from '@sanity/icons'
-import { defineType } from 'sanity'
+import { format, parseISO } from 'date-fns'
+import { defineField, defineType } from 'sanity'
 
 import authorType from './author'
 
@@ -21,62 +22,69 @@ export default defineType({
   icon: BookIcon,
   type: 'document',
   fields: [
-    {
+    defineField({
       name: 'title',
       title: 'Title',
       type: 'string',
       validation: (Rule) => Rule.required(),
-    },
-    {
+    }),
+    defineField({
       name: 'slug',
       title: 'Slug',
       type: 'slug',
       options: {
         source: 'title',
         maxLength: 96,
+        isUnique: (value, context) => context.defaultIsUnique(value, context),
       },
       validation: (Rule) => Rule.required(),
-    },
-    {
+    }),
+    defineField({
       name: 'content',
       title: 'Content',
       type: 'array',
       of: [{ type: 'block' }],
-    },
-    {
+    }),
+    defineField({
       name: 'excerpt',
       title: 'Excerpt',
       type: 'text',
-    },
-    {
+    }),
+    defineField({
       name: 'coverImage',
       title: 'Cover Image',
       type: 'image',
       options: {
         hotspot: true,
       },
-    },
-    {
+    }),
+    defineField({
       name: 'date',
       title: 'Date',
       type: 'datetime',
-    },
-    {
+      initialValue: () => new Date().toISOString(),
+    }),
+    defineField({
       name: 'author',
       title: 'Author',
       type: 'reference',
       to: [{ type: authorType.name }],
-    },
+    }),
   ],
   preview: {
     select: {
       title: 'title',
       author: 'author.name',
+      date: 'date',
       media: 'coverImage',
     },
-    prepare(selection) {
-      const { author } = selection
-      return { ...selection, subtitle: author && `by ${author}` }
+    prepare({ title, media, author, date }) {
+      const subtitles = [
+        author && `by ${author}`,
+        date && `on ${format(parseISO(date), 'LLL d, yyyy')}`,
+      ].filter(Boolean)
+
+      return { title, media, subtitle: subtitles.join(' ') }
     },
   },
 })

schemas/settings.ts

@@ -1,5 +1,5 @@
 import { CogIcon } from '@sanity/icons'
-import { defineType } from 'sanity'
+import { defineField, defineType } from 'sanity'
 
 export default defineType({
   name: 'settings',
@@ -9,13 +9,13 @@ export default defineType({
   // Uncomment below to have edits publish automatically as you type
   // liveEdit: true,
   fields: [
-    {
+    defineField({
       name: 'title',
       description: 'This field is the title of your blog.',
       title: 'Title',
       type: 'string',
       initialValue: 'Blog.',
       validation: (rule) => rule.required(),
-    },
+    }),
   ],
 })