I'm helping with a workflow manager that needs to submit Slurm jobs. For logging and management reasons, the job (e.g. srun python) needs to be run as though it were a regular subprocess (python):

stdin, stdout and stderr for the command should be connected to process inside the job
signals sent to the command should be sent to the job process
We don't want to use the existing job allocation, if this is run from a Slurm job
The command should only terminate when the job is finished, to avoid us needing to poll Slurm

We've tried:

sbatch --wait, but then SIGTERM'ing the process doesn't kill the job
salloc, but that requires a TTY process to control it (?)
salloc srun seems to mess with the terminal when it's killed, likely because of being "designed to be executed in the foreground"
Plain srun re-uses the existing Slurm allocation, and specifying resources like --mem will just request then from the current job rather than submitting a new one

What is the best solution here?