Possible race condition with hashes

[commial]

To reproduce: ask for multiple scans with the same hash at the same time (using the API). The code ends on an error raised by load_from_sha256, because there are several entries in File (in DB) for the same hash...

Maybe related: there is no unique constraint on hash fields in the database, but the case is already considered through the MultipleResultsFound exception catch.

[ch0k0bn]

for reproducing you are scanning multiple times the same files ? (through irma-cli test i guess)

[commial]

We are talking to the REST API, asking to do several different scans containing the same files, but with a "re-scan" enforcement.