func()

in pkg/controllers/member/endpointslice/controller.go [253:325]
37 lines of code
13 McCabe index (conditional complexity)

func (r *Reconciler) shouldSkipOrUnexportEndpointSlice(ctx context.Context,
	endpointSlice *discoveryv1.EndpointSlice) (skipOrUnexportEndpointSliceOp, error) {
	// Skip the reconciliation if the EndpointSlice is not permanently exportable.
	if isEndpointSlicePermanentlyUnexportable(endpointSlice) {
		return shouldSkipEndpointSliceOp, nil
	}

	// If the Service name label is absent, the EndpointSlice is not in use by a Service and thus cannot
	// be exported.
	svcName, hasSvcNameLabel := endpointSlice.Labels[discoveryv1.LabelServiceName]
	// It is guaranteed that if there is no unique name assigned to an EndpointSlice as an annotation, no attempt has
	// been made to export an EndpointSlice.
	_, hasUniqueNameAnnotation := endpointSlice.Annotations[objectmeta.ExportedObjectAnnotationUniqueName]

	if !hasSvcNameLabel {
		if !hasUniqueNameAnnotation {
			// The Service is not in use by a Service and does not have a unique name annotation (i.e. it has not been
			// exported before); it should be skipped for further processing.
			return shouldSkipEndpointSliceOp, nil
		}
		// The Service is not in use by a Service but has a unique name annotation (i.e. it might have been exported);
		// this could happen on an orphaned exported EndpointSlice, which should be unexported.
		return shouldUnexportEndpointSliceOp, nil
	}

	// Retrieve the Service Export.
	svcExport := &fleetnetv1alpha1.ServiceExport{}
	err := r.MemberClient.Get(ctx, types.NamespacedName{Namespace: endpointSlice.Namespace, Name: svcName}, svcExport)
	switch {
	case errors.IsNotFound(err) && hasUniqueNameAnnotation:
		// The Service using the EndpointSlice is not exported but the EndpointSlice has a unique name annotation
		// present (i.e. it might have been exported); the EndpointSlice should be unexported.
		return shouldUnexportEndpointSliceOp, nil
	case errors.IsNotFound(err) && !hasUniqueNameAnnotation:
		// The Service using the EndpointSlice is not exported and the EndpointSlice has no unique name annotation
		// present (i.e. it has not been exported before); the EndpointSlice should be skipped for further processing.
		return shouldSkipEndpointSliceOp, nil
	case err != nil:
		// An unexpected error has occurred.
		return continueReconcileOp, err
	}

	// Check if the ServiceExport is valid with no conflicts.
	if !isServiceExportValidWithNoConflict(svcExport) {
		if hasUniqueNameAnnotation {
			// The Service using the EndpointSlice is not valid for export or has conflicts with other exported
			// Services, but the EndpointSlice has a unique name annotation present (i.e. it might have been
			// exported before); the EndpointSlice should be unexported.
			return shouldUnexportEndpointSliceOp, nil
		}
		// The Service using the EndpointSlice is not valid for export or has conflicts with other exported
		// Services, and the EndpointSlice has no unique name annoation present (i.e. it has not been
		// exported before); the EndpointSlice should be skipped for further processing.
		return shouldSkipEndpointSliceOp, nil
	}

	if endpointSlice.DeletionTimestamp != nil {
		if hasUniqueNameAnnotation {
			// The Service using the EndpointSlice is exported with no conflicts, and the EndpointSlice has a unique
			// name annotation (i.e. it might have been exported), but it has been deleted; as a result,
			// the EndpointSlice should be unexported.
			return shouldUnexportEndpointSliceOp, nil
		}
		// The Service using the EndpointSlice is exported with no conflicts, but the EndpointSlice does not have a
		// unique name annotation (i.e. it has not been exported), and it has been deleted; as a result,
		// the EndpointSlice should be skipped.
		return shouldSkipEndpointSliceOp, nil
	}

	// The Service using the EndpointSlice is exported with no conflicts, and the EndpointSlice is not marked
	// for deletion; the EndpointSlice should be further processed.
	return continueReconcileOp, nil
}