Node DynamoDB Get all records

index.js

const json2xls = require('json2xls');
const {
    convertArrayToCSV
} = require('convert-array-to-csv');
var fs = require('fs');
var AWS = require('aws-sdk');
AWS.config.update({
    region: "us-east-1",
});
var events = new AWS.DynamoDB.DocumentClient();

var params = {
    TableName: 'ses-event'
};

events.scan(params, onScan);
// var count = 1;

var logger = fs.createWriteStream(Date.now() + '.log', {
    flags: 'a' // 'a' means appending (old data will be preserved)
})

var arr = [];
function onScan(err, data) {
    if (err) {
        console.error("Unable to scan the table. Error JSON:", JSON.stringify(err, null, 2));
    } else {
        console.log("Scan succeeded.");
        //esto es para generar un archivo plano
        // console.log(data)
        // data.Items.forEach(function (item) {
        //     // logger.write(count++ + '-' + JSON.stringify(itemdata) + '\r\n');
        //     let from = item.from;
        //     let subject = item.subject;
        //     if (from.includes('[email protected]')) {
        //         // console.log(string);
        //         let obj = {
        //             "from": JSON.parse(item.from),
        //             "to": JSON.parse(item.to),
        //             "subject": item.subject,
        //             "timestamp": item.timestamp
        //         }
        //         console.log(obj);
                
        //         arr.push(obj);
        //     }
        //     // logger.write(JSON.stringify(itemdata));
        // });

        arr.push.apply(arr, data.Items);

        // continue scanning if we have more items
        if (typeof data.LastEvaluatedKey != "undefined") {
            console.log("Scanning for more...");
            params.ExclusiveStartKey = data.LastEvaluatedKey;
            events.scan(params, onScan);
        } else {
            // console.log('last');
            // logger.end();
            //ESTO ES PARA OBTENER UN SOLO ARCHIVO
            var xls = json2xls(arr);
            var path = './' + Date.now() + '.xlsx';
            fs.writeFile(path, xls, 'binary', function (err, data) {
                console.log('create file')
                if (err) {
                    console.log('error')
                    throw err;
                } else {
                    console.log('file Created');
                }
            });
        }
    }
}