[wip] sdk: add operator and builder interface

sdk/builder.go

@@ -0,0 +1,29 @@
+package sdk
+
+type Builder interface {
+	// Name is the name of the operator.
+	Name(name string) Builder
+	// CRDName is the full name of the Custom Resource Resource that the operator operates on.
+	CRDName(crdName string) Builder
+	// APIVersion is the version from the groupVersion.
+	APIVersion(apiVersion string) Builder
+	// Callbacks registers the callbacks which notifies the creation, update, and deletion of any Custom Resource.
+	Callbacks(callBacks CallBacks) Builder
+	// Build builds an operator instance.
+	Build() (Operator, error)
+}
+
+type CallBacks interface {
+	// OnAdd notifies a creation of a Custom Resource.
+	OnAdd(obj interface{})
+	// OnUpdate notifies a update of an existing Custom Resource.
+	OnUpdate(oldObj, newObj interface{})
+	// OnDelete notifies a deletion of an existing Custom Resource.
+	OnDelete(obj interface{})
+}
+
+// NewOperatorBuilder creates a operator builder.
+func NewOperatorBuilder() Builder {
+	// Implement me!
+	return nil
+}

sdk/operatorSDK.go

@@ -0,0 +1,8 @@
+package sdk
+
+import "context"
+
+type Operator interface {
+	// Start starts the operator.
+	Start(Context context.Context) error
+}