Merge pull request #15711 from overleaf/em-migrate-docops-versions

Migrate doc versions from docOps to docs

GitOrigin-RevId: f1d7f68e0e5e869c431c4479766b81c9df355be5

services/web/migrations/20231108221857_move_doc_versions_from_docops_to_docs.js

@@ -0,0 +1,33 @@
+const { ReadPreference } = require('mongodb')
+
+exports.tags = ['server-ce', 'server-pro', 'saas']
+
+exports.migrate = async ({ db }) => {
+  const records = db.docOps.find(
+    {},
+    { readPreference: ReadPreference.secondaryPreferred }
+  )
+
+  let docsProcessed = 0
+  for await (const record of records) {
+    const docId = record.doc_id
+    const version = record.version
+    await db.docs.updateOne(
+      {
+        _id: docId,
+        version: { $exists: false },
+      },
+      { $set: { version } }
+    )
+    docsProcessed += 1
+    if (docsProcessed % 100000 === 0) {
+      console.log(`${docsProcessed} docs processed`)
+    }
+  }
+}
+
+exports.rollback = async ({ db }) => {
+  // Nothing to do on rollback. We don't want to remove versions from the docs
+  // collection because they might be more current than the ones in the docOps
+  // collection.
+}