🏗️ Repopulate featured collection records

refs https://github.com/TryGhost/Arch/issues/95
refs 00e5f84d88

- Maintaining "latest" collection's static content is causing performance issues we are not able to overcome in a short period of time. Instead we leave it as a "dynamic" collection, which equals the contents of the Posts API. The "featured" collection will be saved in a "static" form as previously.
- This is roughly the same migration as in 5.64 version (see refed commit). It wipes out all of the stored collections data and only populates the featured collection.

ghost/core/core/server/data/migrations/versions/5.65/2023-09-22-06-42-15-truncate-stale-built-in-collections-posts.js

@@ -0,0 +1,12 @@
+const logging = require('@tryghost/logging');
+const {createNonTransactionalMigration} = require('../../utils');
+
+module.exports = createNonTransactionalMigration(
+    async function up(knex) {
+        logging.info('Clearing collections_posts table');
+        await knex('collections_posts').truncate();
+    },
+    async function down() {
+        logging.info('Not doing anything - collections_posts table has been truncated');
+    }
+);

ghost/core/core/server/data/migrations/versions/5.65/2023-09-22-06-42-55-repopulate-built-in-featured-collection-posts.js

@@ -0,0 +1,49 @@
+const logging = require('@tryghost/logging');
+const {default: ObjectID} = require('bson-objectid');
+const {createTransactionalMigration} = require('../../utils');
+
+const insertPostCollections = async (knex, collectionId, postIds) => {
+    logging.warn(`Batch inserting ${postIds.length} collection posts for collection ${collectionId}`);
+
+    const collectionPosts = postIds.map((postId) => {
+        return {
+            id: (new ObjectID()).toHexString(),
+            collection_id: collectionId,
+            post_id: postId,
+            sort_order: 0
+        };
+    });
+
+    await knex.batchInsert('collections_posts', collectionPosts, 1000);
+};
+
+module.exports = createTransactionalMigration(
+    async function up(knex) {
+        logging.info('Populating built-in featured collection');
+
+        const existingFeaturedCollection = await knex('collections')
+            .where({
+                slug: 'featured'
+            })
+            .first();
+
+        if (!existingFeaturedCollection) {
+            logging.warn('Featured collection does not exist, skipping');
+        } else {
+            const featuredPostsRows = await knex('posts')
+                .select('id')
+                .where({
+                    featured: true,
+                    type: 'post'
+                });
+
+            const featuredPostsIds = featuredPostsRows.map(row => row.id);
+
+            await insertPostCollections(knex, existingFeaturedCollection.id, featuredPostsIds);
+        }
+    },
+    async function down(knex) {
+        logging.info('Clearing collections_posts table');
+        await knex('collections_posts').truncate();
+    }
+);