Create a presigned URL to upload objects to an Amazon S3 bucket that does not expire

Presigned URLs with very long expiration were possible with Sigv2 signing but not anymore. From a blog article about Sigv2 deprecation: "While using long-lived pre-signed URLs was easy and convenient for developers, using SigV4 with URLs that have a finite expiration is a much better security practice."

So now the longest you can go is 7 days. Note that a presigned URL will expire when the creating IAM principal's credentials expire, so the only way to get expiry over 12 hours is to create it with IAM User credentials.

Why not recreate the functionality in a bucket policy:

{
  "Id": "Policy1677592146473",
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "Stmt1677592144861",
      "Action": [
        "s3:PutObject"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:s3:::mybucket/publicput.doc",
      "Principal": "*"
    }
  ]
}