fix(backfill): fix async handling in firestore to typesense backfill

- Modify `typesenseDocumentFromSnapshot` calls to use `Promise.all`,
ensuring proper handling of asynchronous operations during the
backfill process from Firestore to Typesense.

Author: tharropoulos

functions/src/backfill.js

@@ -36,20 +36,19 @@ module.exports = functions.firestore.document(config.typesenseBackfillTriggerDoc
       `into Typesense Collection ${config.typesenseCollectionName} ` +
       `on ${config.typesenseHosts.join(",")}`);
 
-    if (!validateBackfillRun(snapshot)) {
-      return false;
-    }
+      if (!validateBackfillRun(snapshot)) {
+        return false;
+      }
 
       const typesense = createTypesenseClient();
 
-      const querySnapshot =
-      await admin.firestore().collection(config.firestoreCollectionPath);
-  
+      const querySnapshot = admin.firestore().collection(config.firestoreCollectionPath);
+
       let lastDoc = null;
 
       do {
-        const queryFotThisBatch = lastDoc ? querySnapshot.startAfter(lastDoc) : querySnapshot;
-        const thisBatch = await queryFotThisBatch.limit(config.typesenseBackfillBatchSize).get();
+        const queryForThisBatch = lastDoc ? querySnapshot.startAfter(lastDoc) : querySnapshot;
+        const thisBatch = await queryForThisBatch.limit(config.typesenseBackfillBatchSize).get();
         if (thisBatch.empty) {
           break;
         }
@@ -65,13 +64,9 @@ module.exports = functions.firestore.document(config.typesenseBackfillTriggerDoc
               .import(currentDocumentsBatch);
           functions.logger.info(`Imported ${currentDocumentsBatch.length} documents into Typesense`);
         } catch (error) {
-          if (error.importResults) {
-            const failedItems = error.importResults.filter(
-                (r) => r.success === false,
-            );
-            functions.logger.error("Import failed with document errors", failedItems);
-          } else {
-            functions.logger.error("Import error", error);
+          functions.logger.error(`Import error in a batch of documents from ${currentDocumentsBatch[0].id} to ${lastDoc.id}`, error);
+          if ("importResults" in error) {
+            logImportErrors(error.importResults);
           }
         }
 
@@ -83,16 +78,8 @@ module.exports = functions.firestore.document(config.typesenseBackfillTriggerDoc
         await new Promise((resolve) => process.nextTick(resolve));
       } while (lastDoc);
 
-      if (currentDocumentsBatch.length < config.typesenseBackfillBatchSize) {
-        break;
-      }
-      // Recurse on the next process tick, to avoid
-      // issues with the event loop on firebase functions related to resource release
-      await new Promise((resolve) => process.nextTick(resolve));
-    }
-
-    functions.logger.info("Done backfilling to Typesense from Firestore");
-  });
+      functions.logger.info("Done backfilling to Typesense from Firestore");
+    });
 
 function logImportErrors(importResults) {
   importResults.forEach((result) => {

functions/src/backfillToTypesenseFromFirestore.js

@@ -50,7 +50,9 @@ module.exports = functions.handler.firestore.document
         if (thisBatch.empty) {
           break;
         }
-        const currentDocumentsBatch = thisBatch.docs.map((doc) => utils.typesenseDocumentFromSnapshot(doc));
+        const currentDocumentsBatch = await Promise.all(thisBatch.docs.map(async (doc) => {
+          return await utils.typesenseDocumentFromSnapshot(doc);
+        }));
 
         lastDoc = thisBatch.docs.at(-1) ?? null;
         try {