1const AWS = require('aws-sdk');
2AWS.config.update(
3  {
4    accessKeyId: "....",
5    secretAccessKey: "...",
6    region: 'ap-southeast-1'
7  }
8);
9const s3 = new AWS.S3();
10const options = {
11  Bucket    : '/bucket-url',
12  Key    : fileKey,
13};
14const fileStream = s3.getObject(options).createReadStream();
15fileStream.pipe(res);