Importing Large Data from BigQuery to Firestore using CloudFunctions

fetch_data

const {BigQuery} = require("@google-cloud/bigquery");
const firebaseConfig =  require('firebase-admin');

firebaseConfig.initializeApp();

const firestoreDb = firebaseConfig.firestore();

var batchCommits = [];

var batch = firestoreDb.batch();

var counter = 0;

 exports.fetchAdminTwo = (req,res) =>{
     var bigQuery = new BigQuery({ projectId: 'fao-empres-re' });

     var sqlStatement = 'SELECT id, id_admin1, description_en, description_fr, description_es, latitude, longitude FROM `fao-empres-re.empres_data.admin2`;';

     console.log('Triggering bigquery to execute sql statement');

     return bigQuery.query({query:sqlStatement}).then(results =>{
         var adminList = results[0];
         console.log('Query results:',adminList);

         res.send(adminList);

         adminList.forEach((admin,i) =>{
             var collectionRef = firestoreDb.collection('ref-admins-two').doc();
             batch.set(collectionRef,admin);
             console.log('Doc ID:',collectionRef.id,'Count:',counter++);
             if ((i + 1) % 500 === 0) {
                 console.log(`Batch count: ${i + 1}`);
                 batchCommits.push(batch.commit());
                 batch = firestoreDb.batch();
                 }
         });
         batchCommits.push(batch.commit());
         return Promise.all(batchCommits);

    }).catch(error =>{
        console.log("Query error:",error);
        });
 }