Limit number of downloads #10
Description
It might be useful to have an optional feature to limit the amount of downloads.
Potential benefits include
- Limiting the blast radius of denial of wallet attacks
- Enabling "self-destructing" download links that are valid for one download only, e.g. for sending sensitive information
Thoughts on how to implement that
- Use DynamoDB table item attributes to track current and max downloads counters
- Alternative: Store current and max downloads counters as object metadata on each uploaded file. Would alleviate need for separate database but would add more latency since S3 would effectively act as a database. The biggest downside I see for that option: in order to change object metadata you need to create a copy of that object.