Reimplementation of the helm operator to enrich the Helm operator's reconciliation with custom Go code to create a hybrid operator.
The Helm operator type automates Helm chart operations by mapping the values of a Helm chart exactly to a CustomResourceDefinition and defining its watched resources in a watches.yaml configuration file.
For creating a Level II+ operator that reuses an already existing Helm chart, a hybrid between the Go and Helm operator types is necessary.
The hybrid approach allows adding customizations to the Helm operator, such as:
- value mapping based on cluster state, or
- executing code in specific events.
// Operator's main.go chart, err := loader.Load("path/to/chart") if err != nil { panic(err) } reconciler := reconciler.New( reconciler.WithChart(*chart), reconciler.WithGroupVersionKind(gvk), ) if err := reconciler.SetupWithManager(mgr); err != nil { panic(fmt.Sprintf("unable to create reconciler: %s", err)) }Add the WATCH_NAMESPACE to the manager files to restrict the namespace to observe where the operator is installed
name: manager env: - name: WATCH_NAMESPACE valueFrom: fieldRef: fieldPath: metadata.namespaceFilter the events to the namespace where the operator is installed
// Operator's main.go watchNamespace = os.Getenv("WATCH_NAMESPACE") var cacheOpts cache.Options if watchNamespace != "" { setupLog.Info("Watching specific namespace", "namespace", watchNamespace) cacheOpts = cache.Options{ DefaultNamespaces: map[string]cache.Config{ watchNamespace: {}, }, } } else { setupLog.Info("Watching all namespaces") } mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{ ... Cache: cacheOpts, }) ... chart, err := loader.Load("path/to/chart") if err != nil { panic(err) } reconciler := reconciler.New( reconciler.WithChart(*chart), reconciler.WithGroupVersionKind(gvk), ) if err := reconciler.SetupWithManager(mgr); err != nil { panic(fmt.Sprintf("unable to create reconciler: %s", err)) }