shim lifecycle operator

[0xE282B0]

Based on the proposal by @devigned: https://hackmd.io/@devigned/SJJPWsAj2

Objective:
Test whether the [proposed CRD] (https://hackmd.io/@devigned/SJJPWsAj2#Shim-CRD) is appropriate for the planned lifecycle operations:

• Install
• Upgrade/Downgrade
• Remove

Suggested requirements:

• Keep operator installation as simple as possible
• Single shim installation without operator should be possible
• The CRD is a cluster-wide resource.
• The installer is not responsible for downloading the binaries.
  • may be downloaded from another init container and mounted via emptyDir
  • It should still be possible to build an installer image with the shims to install baked in.
• If no nodeSelector is given in the CRD, all nodes will be provisioned.
  • The default behavior changes from the kwasm.sh/kwasm-node=true annotation to kwasmOperator.autoProvision="true".

UPDATE, 01. September. '23:
This becomes the tracking issue for the lifecycle management feature.

Tasks:

• Initialize branch https://github.com/KWasm/kwasm-operator/tree/kwasm-lifecycle-manager with operator SDK
• Create custom resource "shim" to deploy containerd shims
• Schedule shim deployment on nodes via Kubernetes Job
• Schedule shim deployment on nodes adhering according to spec.nodeSelector
• Automatically create RuntimeClass for each shim
• Uninstall shim on nodes when CR is deleted
• Handle node label changes (e.g. uninstall shim on node if label is removed; install it if a label is added)
• Create operator images for distribution
• Create node-installer images for distribution
• Implement rolling update strategy

[OliverMKing]

@0xE282B0 is this being actively worked on? I'm interested in picking up some of the work.

[0xE282B0]

@OliverMKing, Yes, kind of. At least it is at the top of my ToDo list 😅
We have a channel in the CNCF Slack: https://cloud-native.slack.com/archives/C05P2KNK7RV
Let's see if we can break it down and get started.

[voigt]

Development of shim-lifecycle-operator moved over to https://github.com/spinkube/runtime-class-manager.