KubeTemplateSpawner

⚠️⚠️⚠️⚠️⚠️ Under development ⚠️⚠️⚠️⚠️⚠️

A JupyterHub Kubernetes spawner that uses Kubernetes templates.

How this works

This takes a set of parameterised Helm templates that deploy a JupyterHub singleuser server, then:

• creates a temporary Helm values.yaml file with JupyterHub template variables
• runs helm template ...
• deploys the templated manifests

The following template variables are available

Raw user and server:

• userid
• unescaped_username
• unescaped_servername

Escaped user and server (based on the KubeSpawner safe scheme):

• escaped_username
• escaped_servername
• escaped_user_server

Spawner variables:

• instance: Instance name to distinguish multiple JupyterHub deployments
• namespace: Kubernetes namespace
• ip: IP the server should listen on
• port Port the server should listen on
• env: Dictionary of key: value environment variables

Additional variables:

• Variables from KubeTemplateSpawner.extra_vars are included, and can override the above

Labels

All resources must include an instance label to distinguish multiple deployments:

• app.kubernetes.io/instance: {{ .Values.instance }}

User resources must include:

• hub.jupyter.org/username: "{{ .Values.escaped_username }}"

User server resources (that aren't shared between default and named servers) must also include:

• hub.jupyter.org/servername: "{{ .Values.escaped_servername }}"

Connection annotation:

• kubetemplatespawner/connection=true: One resource per server (either a pod or service) must have this annotation to indicate JupyterHub should use this resource to connect to the server

Lifecycle/deletion

These control when resources are deleted.

• kubetemplatespawner/lifecycle=user-deleted: Delete this resource when the user is deleted, typically used for storage volumes
• kubetemplatespawner/lifecycle=server-stopped: Delete this resource when the user server is stopped, typically the default for most resources other than persistent storage
• kubetemplatespawner/lifecycle=server-deleted: Delete this resource when a named server is deleted, use this if a named server has a separate storage volume that doesn't need to be kept

Resources are deleted by matching all labels:

• app.kubernetes.io/instance: {{ .Values.instance }}
• hub.jupyter.org/username: "{{ .Values.escaped_username }}"
• hub.jupyter.org/servername: "{{ .Values.escaped_servername }}" (servers only)

Example

https://github.com/manics/jupyterhub-kubetemplatespawner/tree/main/z2jh