The ondemand-compute RPM will pull in the python-websockify RPM and TurboVNC from OnDemand repos as well as depend on nmap-ncat and a few other programs we require: https://github.com/OSC/ondemand-packaging/blob/master/packages/ondemand-compute/ondemand-compute.spec#L11-L16
To utilize the RPM based websockify and turbovnc for interactive jobs, you will need something like this in your cluster YAML config: https://github.com/ubccr/hpc-toolset-tutorial/blob/master/ondemand/cluster-config.yml#L12-L17