Once a user account is created it can be used to transfer the files using the SFTP. The credential of user remain as defined for the UI. In addition, a user can add as many as public keys as needed for the password less authentication.
sftp -oIdentityFile=~/.ssh/id_rsa firstname.lastname@example.org <<EOF mkdir Home/today put ./2020-03-05_00-02-06.png Home/today put ./2020-03-05_15-28-13.png Home/today EOF
Use one of the clients:
Note: Using SFTP as a distributed filesystem is using it for something it's not designed for. The ability to cache, read ahead or detect network disruptions is dependent on the quality of the implementation of the client, which has to do with an underlying protocol not designed for this purpose.