LambdaからS3にあるjsonファイルを取得 node.js編

var aws = require('aws-sdk');
aws.config.region = 'ap-northeast-1';
var bucket = 'bucketName';
var s3 = new aws.S3();

exports.handler = function(event, context) {
   
    var params = {
        Bucket: bucket,
        Key: 'sample.json'
    };
    s3.getObject(params, function(err, data) {
        if (err) {
            console.log(err, err.stack);
        } else {
            var object = JSON.parse(data.Body.toString());
            console.log(object);
        }
    });
}