PhotoUpload.js

let s3Params = {
   Bucket: "your-temporary-bucket-name,
   Conditions : [
       ["content-length-range",1,31457280]
   ],
   Fields : {
       key: "path/to/your/object"
   },
   Expires: 300 //in seconds
};
const s3 = new S3({region : process.env.AWSREGION });
s3.createPresignedPost(s3Params)