runtime-class-manager

The runtime-class-manager is the spiritual successor to the kwasm-operator. kwasm has been developed as an experimental, simple way to install Wasm runtimes. This experiment has been relatively successful, as more and more users utilized it to fiddle around with Wasm on Kubernetes. However, the kwasm-operator has some limitations that make it difficult to use in production. The runtime-class-manager is an attempt to address these limitations to make it a reliable and secure way to deploy arbitrary containerd shims.

The implementation of runtime-class-manager follows this community proposal.

The name should be treated as a working title and is hopefully subject to change.

Roadmap

For the 1.0 release of runtime-class-manager, we consider three milestones:

• M1: RCM MVP for Spinkube
  This milestone is about getting RCM to a state where Spinkube can rely on RCM and use it as a dependency instead of Kwasm. This means, that the focus is on managing lifecycle of containerd-shim-spin on nodes.
• M2: Kwasm Feature Parity
  All shims that kwasm can install, should be installable via rcm. Automated tests are in place to ensure installation of RCM and shims that are supported by Kwasm.
• M3: Full implementation of the initial spec
  Stable spec of the Shim CRD based on the initial proposal. After 1.0 we assume no breaking changes of the Shim CRD. Arbitrary shims can be installed via RCM and prominent shims are tested automatically, on various Kubernetes distributions.
• Future (ideas):
  • support for additional container runtimes, like CRI-O to enable RCM on OpenShift
  • alternative shim installation via Daemonset instead of Jobs
  • treating node-installer as a daemon process, to enable better conflict resolution

Usage

To Deploy on the cluster

Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/runtime-class-manager:tag

NOTE: This image ought to be published in the personal registry you specified. And it is required to have access to pull the image from the working environment. Make sure you have the proper permission to the registry if the above commands don’t work.

Install the CRDs into the cluster:

make install

Deploy the Manager to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/runtime-class-manager:tag

NOTE: If you encounter RBAC errors, you may need to grant yourself cluster-admin privileges or be logged in as admin.

Create instances of your solution You can apply the samples (examples) from the config/sample:

kubectl apply -k config/samples/

NOTE: Ensure that the samples has default values to test it out.

To Uninstall

Delete the instances (CRs) from the cluster:

kubectl delete -k config/samples/

Delete the APIs(CRDs) from the cluster:

make uninstall

UnDeploy the controller from the cluster:

make undeploy

License

Copyright 2024.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.