Notebook with kernel process

We support to start a notebook with a separated kernel process, and it could be enabled by PRIMEHUB_FEATURE_ENABLE_KERNEL_GATEWAY flag.

Basic idea

After notebook 6.0.0, it support the nb2kg (notebook to kernel gateway) feature and we could use different image to serve notebook and kernel process.

The benefit is:

1. keep notebook as view to user, we maintain some front package, such as npm module and notebook extension for notebook.

2. kernel image only to install notebook kernel modules and jupyter-kernel-gateway package

To separate frontend (notebook) and backend (kernel) could avoid to maintain lots of combination of software packages and versions.

Implementation

By default, primehub instance launches a notebook using a image that is a user picked in the spwaner page.

For seperated kernel process:

1. using a user selected image to launch kernel process

• we install kernel-gateway package before launch kernel process

2. launching notebook process with our prebuilt or standard notebook image (any image contains nb2kg package)

3. overwrite the annotation auditing.image with use selected image

Any resources settings are moving to kernel container's resource spec and unset resource spec in the notebook container.

Future Work

1. should support air-gap with a prebuilt kernel-gateway (for now, we do it by pip install)