Write script to fix old comments without IDs and user IDs (#680)

functions/src/scripts/backfill-comment-ids.ts

@@ -0,0 +1,55 @@
+// We have some old comments without IDs and user IDs. Let's fill them in.
+// Luckily, this was back when all comments had associated bets, so it's possible
+// to retrieve the user IDs through the bets.
+
+import * as admin from 'firebase-admin'
+import { QueryDocumentSnapshot } from 'firebase-admin/firestore'
+import { initAdmin } from './script-init'
+import { log, writeAsync } from '../utils'
+import { Bet } from '../../../common/bet'
+
+initAdmin()
+const firestore = admin.firestore()
+
+const getUserIdsByCommentId = async (comments: QueryDocumentSnapshot[]) => {
+  const bets = await firestore.collectionGroup('bets').get()
+  log(`Loaded ${bets.size} bets.`)
+  const betsById = Object.fromEntries(
+    bets.docs.map((b) => [b.id, b.data() as Bet])
+  )
+  return Object.fromEntries(
+    comments.map((c) => [c.id, betsById[c.data().betId].userId])
+  )
+}
+
+if (require.main === module) {
+  const commentsQuery = firestore.collectionGroup('comments')
+  commentsQuery.get().then(async (commentSnaps) => {
+    log(`Loaded ${commentSnaps.size} comments.`)
+    const needsFilling = commentSnaps.docs.filter((ct) => {
+      return !('id' in ct.data()) || !('userId' in ct.data())
+    })
+    log(`${needsFilling.length} comments need IDs.`)
+    const userIdNeedsFilling = needsFilling.filter((ct) => {
+      return !('userId' in ct.data())
+    })
+    log(`${userIdNeedsFilling.length} comments need user IDs.`)
+    const userIdsByCommentId =
+      userIdNeedsFilling.length > 0
+        ? await getUserIdsByCommentId(userIdNeedsFilling)
+        : {}
+    const updates = needsFilling.map((ct) => {
+      const fields: { [k: string]: unknown } = {}
+      if (!ct.data().id) {
+        fields.id = ct.id
+      }
+      if (!ct.data().userId && userIdsByCommentId[ct.id]) {
+        fields.userId = userIdsByCommentId[ct.id]
+      }
+      return { doc: ct.ref, fields }
+    })
+    log(`Updating ${updates.length} comments.`)
+    await writeAsync(firestore, updates)
+    log(`Updated all comments.`)
+  })
+}