actuator.go

// SPDX-FileCopyrightText: 2024 SAP SE or an SAP affiliate company and Gardener contributors
//
// SPDX-License-Identifier: Apache-2.0

package operatingsystemconfig

import (
	"context"
	_ "embed"
	"fmt"

	"github.com/go-logr/logr"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/manager"

	"github.com/gardener/gardener/extensions/pkg/controller/operatingsystemconfig"
	extensionsv1alpha1 "github.com/gardener/gardener/pkg/apis/extensions/v1alpha1"
)

type actuator struct {
	client client.Client
}

// NewActuator creates a new Actuator that updates the status of the handled OperatingSystemConfig resources.
func NewActuator(mgr manager.Manager) operatingsystemconfig.Actuator {
	return &actuator{
		client: mgr.GetClient(),
	}
}

func (a *actuator) Reconcile(ctx context.Context, _ logr.Logger, osc *extensionsv1alpha1.OperatingSystemConfig) ([]byte, []extensionsv1alpha1.Unit, []extensionsv1alpha1.File, error) {
	switch purpose := osc.Spec.Purpose; purpose {
	case extensionsv1alpha1.OperatingSystemConfigPurposeProvision:
		userData, err := a.handleProvisionOSC(ctx, osc)
		return []byte(userData), nil, nil, err

	case extensionsv1alpha1.OperatingSystemConfigPurposeReconcile:
		extensionUnits, extensionFiles, err := a.handleReconcileOSC(osc)
		return nil, extensionUnits, extensionFiles, err

	default:
		return nil, nil, nil, fmt.Errorf("unknown purpose: %s", purpose)
	}
}

func (a *actuator) Delete(_ context.Context, _ logr.Logger, _ *extensionsv1alpha1.OperatingSystemConfig) error {
	return nil
}

func (a *actuator) Migrate(ctx context.Context, log logr.Logger, osc *extensionsv1alpha1.OperatingSystemConfig) error {
	return a.Delete(ctx, log, osc)
}

func (a *actuator) ForceDelete(ctx context.Context, log logr.Logger, osc *extensionsv1alpha1.OperatingSystemConfig) error {
	return a.Delete(ctx, log, osc)
}

func (a *actuator) Restore(ctx context.Context, log logr.Logger, osc *extensionsv1alpha1.OperatingSystemConfig) ([]byte, []extensionsv1alpha1.Unit, []extensionsv1alpha1.File, error) {
	return a.Reconcile(ctx, log, osc)
}

func (a *actuator) handleProvisionOSC(ctx context.Context, osc *extensionsv1alpha1.OperatingSystemConfig) (string, error) {
	writeFilesToDiskScript, err := operatingsystemconfig.FilesToDiskScript(ctx, a.client, osc.Namespace, osc.Spec.Files)
	if err != nil {
		return "", err
	}
	writeUnitsToDiskScript := operatingsystemconfig.UnitsToDiskScript(osc.Spec.Units)

	script := `#!/bin/bash
` + writeFilesToDiskScript + `
` + writeUnitsToDiskScript + `
systemctl daemon-reload
`
	for _, unit := range osc.Spec.Units {
		script += fmt.Sprintf(`systemctl enable '%s' && systemctl restart --no-block '%s'
`, unit.Name, unit.Name)
	}

	return script, nil
}

func (a *actuator) handleReconcileOSC(_ *extensionsv1alpha1.OperatingSystemConfig) ([]extensionsv1alpha1.Unit, []extensionsv1alpha1.File, error) {
	// provider-local does not add any additional units or additional files
	return nil, nil, nil
}