Allow setting some metadata when manually submitting a file

[kam193]

Is your feature request related to a problem? Please describe.
The API allows us to flexible set metadata of a submission, but it's not possible when manually submitting data. I usually fill them when automatically uploading files via API, but occasionally, I want to analyze files intentionally skipped by the automation. I miss then the ability to mark and correlate them.

In another context, if you have a separated ticketing system and manually upload related data, you would like to add a related ticket ID to easily connect them.

Describe the solution you'd like
I'd suggest letting administrators configure metadata fields that can be filled during the manual upload.

Describe alternatives you've considered

• Letting declare any metadata field, as in API - but this would quickly lead to a big mess.
• Marking some metadata as required - it could be interesting, a ticket ID is a great example here.
• More complex validation, e.g. declaring a field with a list of allowed values - interesting but in my opinion, too much work if not being explicitly requested

Additional context