Scheduled firestore backup

backup.js

const functions = require('firebase-functions');
const firestore = require('@google-cloud/firestore');
const { storageBucket, projectId } = require('...');

const client = new firestore.v1.FirestoreAdminClient();

const firestoreBackup = functions
  .runWith({ memory: '512MB', timeoutSeconds: 540 })
  .pubsub
  .schedule('every 24 hours')
  .onRun(() => { // param context is available
    const databaseName = client.databasePath(projectId, '(default)');
    const time = new Date().getTime();

    return client.exportDocuments({
      name: databaseName,
      outputUriPrefix: `${storageBucket}/backup/firestore/${time}`,
      // Leave collectionIds empty to export all collections
      // or set to a list of collection IDs to export,
      // collectionIds: ['users', 'posts']
      collectionIds: [],
    }).then((responses) => {
      const response = responses[0];
      return console.log(`Operation Name: ${response.name}`);
    }).catch((err) => {
      console.error(err);
      throw new Error('Export operation failed');
    });
  });

module.exports = { firestoreBackup };