Building Better Controllers - John Howard, Google

Don't miss out! Join us at our next Flagship Conference: KubeCon + CloudNativeCon Europe in Paris from March 19-22, 2024. Connect with our current graduated, incubating, and sandbox projects as the community gathers to further the education and advancement of cloud native computing. Learn more at https://kubecon.io Building Better Controllers - John Howard, Google Controllers are a foundational part of Kubernetes, from creating Pods in response to Deployments, or complex third-party controllers added bespoke logic to a Kubernetes cluster. While incredibly powerful, controllers are also subtly tricky to build correctly; while projects like kube-builder do an excellent job of lowering the barrier to entry of writing controllers, there is still substantial complexity involved in creating a controller, especially a non-trivial one. I will: * explain why writing controllers can be so challenging, with lessons learned from maintaining Istio's 20+ controllers. * show common problems faced by all implementations (including some examples of bugs in Kubernetes core) * introduce a new architecture for controllers that makes implementation easier and less error prone, including a demo of development of a simple controller. * explore some benefits of this approach and give a sneak peek of what the future of Kubernetes controllers could look like.