MinIO

Engine: S3-compatible (AWS SigV4) · Preset: MinIO / self-hosted S3

This page is also the answer for any S3-compatible server you run yourself — Garage, SeaweedFS, Ceph RGW, Zenko, Backblaze B2's S3 endpoint, Wasabi, DigitalOcean Spaces. The fields are the same; only the endpoint changes.

Configuration#

Settings → Hosts → + → MinIO / self-hosted S3.

Include the port if the server does not run on 443 or 80. Dropline signs the host with its port, so https://s3.example.com:9000 and https://s3.example.com are different hosts as far as the signature is concerned — use whichever you actually reach the server on.

Dropline always uses path-style addressing (endpoint/bucket/key), which is MinIO's native mode. There is nothing to configure for it, and you do not need wildcard DNS or virtual-host style.

Other providers' endpoints, for reference:

Create a scoped access key#

In the MinIO console, Access Keys → Create access key, and attach a policy so a leaked key cannot do more than upload:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": ["s3:PutObject"],
      "Resource": ["arn:aws:s3:::assets/images/*"]
    }
  ]
}

Do not hand Dropline the root credentials from MINIO_ROOT_USER.

Make objects readable#

Anonymous download on one prefix, with the mc client:

mc alias set local http://127.0.0.1:9000 ACCESSKEY SECRETKEY
mc anonymous set download local/assets/images

Or in the console: bucket → Anonymous → add a rule with readonly access on the prefix.

Serving the links#

If MinIO is reachable at a public hostname, leave Public base URL empty and Dropline returns:

https://s3.example.com/assets/images/2026/08/19/a1f3….png

If a reverse proxy or CDN serves the bucket at a cleaner path, set the base URL to it. A typical nginx front-end that strips the bucket:

Public base URL   https://cdn.example.com

pairs with a proxy that maps / to /assets/ upstream.

Localhost caveat#

http://127.0.0.1:9000 is perfect for testing — Test Upload will pass — but the returned link only works on your own machine. Anything you share from a localhost profile is a dead link for everyone else.

Common problems#