A comprehensive guide to building Kubernetes operators using Go and the controller-runtime library. The tutorial walks through creating a custom DatabaseMigration operator called kube-shift, covering project scaffolding with Kubebuilder, defining Custom Resource Definitions (CRDs), implementing the reconciliation loop, and advanced concepts like status updates, finalizers, and leader election. Includes testing strategies with both unit and integration tests using envtest.
Table of contents
The "Why": What Problem Do Operators Solve?Setting the Stage: Project Scaffolding with KubebuilderDefining Our Custom Resource: The DatabaseMigration CRDThe Heart of the Operator: The Controller and Reconciliation LoopConclusionSort: