Docker Swarm Secrets (+Portainer)

I run my Node-Red on Docker Swarm + Portainer.
I was wondering how can I define multiple credentials (multiple environment variables)? From what I found, I have to edit the "credentialsSecret" inside settings.js, but I have several credentials.
Another issue that I don't know how to address is the docker swarm secrets - say I've defined some secrets in the service, how can I access them through the editor itself?

Thanks in advance!