Update to dask-gateway==0.7.1

[TomAugspurger]

Updates the requriement and configuration.

Some additional cleanup of the config to move common settings from binder & the hubs here.

[TomAugspurger]

cc @scottyhq.

[consideRatio]

This LGTM, for your reference, this is my setup.

I would consider adding traefik.service.type: ClusterIP, because by default it is a LoadBalancer that exposes it with a public IP, but you access it through JupyterHub's configurable proxy and /services/dask-gateway anyhow, which means you use that entrypoint to the k8s cluster rather than directly through the dask-gateways traefik service.

# my sensitive values redacted
gateway:
  proxyToken: redacted
  auth:
    type: jupyterhub
    jupyterhub:
      # A JupyterHub api token for dask-gateway to use. See
      # https://gateway.dask.org/install-kube.html#authenticating-with-jupyterhub.
      apiToken: redacted

      # JupyterHub's api url. Inferred from JupyterHub's service name if running
      # in the same namespace.
      apiUrl: http://hub.jupyterhub:8081/hub/api

# my non-sensitive values.yaml
gateway:
  loglevel: DEBUG
  resources: {}
  # Path prefix to serve dask-gateway api requests under
  # This prefix will be added to all routes the gateway manages
  # in the traefik proxy.
  prefix: /services/dask-gateway
  backend:
    # The image to use for both schedulers and workers.
    image:
      name: <our jupyterhub user environment image>
      tag: <...>
    # A mapping of environment variables to set for both schedulers and workers.
    environment: null
    scheduler:
      # Any extra configuration for the worker pod. Sets
      # `c.KubeClusterConfig.worker_extra_pod_config`.
      extraPodConfig:
        tolerations:
          - key: "hub.jupyter.org_dedicated"
            operator: "Equal"
            value: "user"
            effect: "NoSchedule"
        nodeSelector:
          hub.jupyter.org/node-purpose: user
      # Any extra configuration for the worker container. Sets
      # `c.KubeClusterConfig.worker_extra_container_config`.
      extraContainerConfig: {}
      cores:
        request: 0.05
        limit: 1
      memory:
        request: 0.25G
        limit: 2G
    worker:
      # Any extra configuration for the worker pod. Sets
      # `c.KubeClusterConfig.worker_extra_pod_config`.
      extraPodConfig:
        tolerations:
          - key: "dedicated"
            operator: "Equal"
            value: "dask-workers"
            effect: "NoSchedule"
        nodeSelector:
          node-purpose: dask-workers
      # Any extra configuration for the worker container. Sets
      # `c.KubeClusterConfig.worker_extra_container_config`.
      extraContainerConfig: {}

      cores:
        request: 0.1
        limit: 1
      memory:
        request: 3.45G
        limit: 3.45G

  # ref: https://gateway.dask.org/install-kube.html#using-extraconfig
  extraConfig:
    user-resource-limits: |
      # ref: https://gateway.dask.org/resource-limits.html
      c.UserLimits.max_clusters = 1
      c.UserLimits.max_cores = 32
      c.UserLimits.max_memory = str(3.45 * c.UserLimits.max_cores) + " GB"
    cluster-options: |
      # ref: https://gateway.dask.org/cluster-options.html

      from dask_gateway_server.options import Options, Integer, Float, String
      def option_handler(options):
          return {
              "worker_cores": options.worker_cores,
              "worker_memory": "%fG" % options.worker_memory,
          }

      c.Backend.cluster_options = Options(
          Integer("worker_cores", 1, min=1, max=4, label="Worker Cores"),
          Float("worker_memory", 3.45, min=1, max=13.8, label="Worker Memory (GiB)"),
          handler=option_handler,
      )

# Configuration for the gateway controller
controller:
  loglevel: DEBUG
  resources: {}

# Configuration for the traefik proxy
traefik:
  loglevel: DEBUG
  resources: {}
  # Additional configuration for the traefik service
  service:
    # Let's only provide access to the proxy of traffic internally in the k8s
    # cluster, and if we want external access, we can add an ingress resource.
    type: ClusterIP

[TomAugspurger]

Going to merge this and attempt to update to the staging hubs.