adding nbgrader groups

[bpfrd]

Hi,
in the bootstrap_pre_spawn function, you loop over courses and create formgrade-groups and roles as below:

groupsToCreate = {}

        base_port = 9000
        idx = 0
        for course, instructors in COURSES.items():
          # "outbound" must exist before starting a singleuser 
          if not os.path.exists(f'/mnt/exchange/{course}/outbound'):
            os.makedirs(f"/mnt/exchange/{course}/outbound")
          if not os.path.exists(f'/mnt/exchange/{course}/inbound'):
            os.makedirs(f"/mnt/exchange/{course}/inbound")
          if not os.path.exists(f'/mnt/exchange/{course}/feedback_public'):
            os.makedirs(f"/mnt/exchange/{course}/feedback_public")
          
          with open(f"/mnt/exchange/{course}/nbgrader_config.py", "w") as f:
            f.write("c = get_config()\n")
            f.write(f"c.CourseDirectory.root = '/mnt/exchange/{course}'\n")
            f.write(f"c.CourseDirectory.course_id = '{course}'\n")

          c.JupyterHub.services.append(
            {
              "name": course,
              "url": f"http://course-svc:{base_port + idx}",
              "command": ["jupyterhub-singleuser", f"--group=formgrade-{course}", f"--port={base_port + idx}", "--debug", "--ServerApp.ip=0.0.0.0"],
              "cwd": f"/mnt/exchange/{course}",
              "oauth_no_confirm": True,
              "environment" : {
                # Here nbgrader.auth.JupyterHubAuthPlugin needs a user, that always exists
                "JUPYTERHUB_USER": "admin"
              }
            }
          )

          groupsToCreate[f"nbgrader-{course}"] = []
          groupsToCreate[f"formgrade-{course}"] = instructors

          c.JupyterHub.load_roles.append({
            "name": f"formgrade-{course}",
            "groups": [f"formgrade-{course}"],
            "services": [course],
            "scopes": [
              f"access:services!service={course}", 
              f"read:services!service={course}", 
              f"list:services!service={course}", 
              "groups", 
              "users"
            ]
          })
          idx += 1

        c.JupyterHub.load_groups = groupsToCreate

what should I add if I want to create nbgrader- groups for students as well? in particular, should I create a service and add a role?
what rbac scopes should the role have?

best