gitpod/components/ws-manager-mk2/controllers/maintenance_controller.go

115 lines
3.3 KiB
Go

// Copyright (c) 2023 Gitpod GmbH. All rights reserved.
// Licensed under the GNU Affero General Public License (AGPL).
// See License.AGPL.txt in the project root for license information.
package controllers
import (
"context"
"encoding/json"
"fmt"
"sync"
"time"
"github.com/gitpod-io/gitpod/ws-manager/api/config"
corev1 "k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/types"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/log"
)
var (
configMapKey = types.NamespacedName{Name: "ws-manager-mk2-maintenance-mode", Namespace: "default"}
// lookupOnce is used for the first call to IsEnabled to load the maintenance mode state by looking
// up the ConfigMap, as it's possible we haven't received a reconcile event yet to load its state.
lookupOnce sync.Once
)
func NewMaintenanceReconciler(c client.Client) (*MaintenanceReconciler, error) {
return &MaintenanceReconciler{
Client: c,
enabledUntil: nil,
}, nil
}
type MaintenanceReconciler struct {
client.Client
enabledUntil *time.Time
}
func (r *MaintenanceReconciler) IsEnabled(ctx context.Context) bool {
// On the first call, we load the maintenance mode state from the ConfigMap,
// as it's possible we haven't reconciled it yet.
lookupOnce.Do(func() {
if err := r.loadFromCM(ctx, configMapKey); err != nil {
log.FromContext(ctx).Error(err, "cannot load maintenance mode config")
}
})
return r.enabledUntil != nil && time.Now().Before(*r.enabledUntil)
}
//+kubebuilder:rbac:groups=core,resources=configmap,verbs=get;list;watch
func (r *MaintenanceReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
if req.Name != configMapKey.Name || req.Namespace != configMapKey.Namespace {
// Ignore all other configmaps.
return ctrl.Result{}, nil
}
return ctrl.Result{}, r.loadFromCM(ctx, req.NamespacedName)
}
func (r *MaintenanceReconciler) loadFromCM(ctx context.Context, key types.NamespacedName) error {
log := log.FromContext(ctx)
var cm corev1.ConfigMap
if err := r.Get(ctx, key, &cm); err != nil {
if errors.IsNotFound(err) {
// ConfigMap does not exist, disable maintenance mode.
r.setEnabledUntil(ctx, nil)
return nil
}
log.Error(err, "unable to fetch configmap")
return fmt.Errorf("failed to fetch configmap: %w", err)
}
configJson, ok := cm.Data["config.json"]
if !ok {
log.Info("missing config.json, setting maintenance mode as disabled")
r.setEnabledUntil(ctx, nil)
return nil
}
var cfg config.MaintenanceConfig
if err := json.Unmarshal([]byte(configJson), &cfg); err != nil {
log.Error(err, "failed to unmarshal maintenance config, setting maintenance mode as disabled")
r.setEnabledUntil(ctx, nil)
return nil
}
r.setEnabledUntil(ctx, cfg.EnabledUntil)
return nil
}
func (r *MaintenanceReconciler) setEnabledUntil(ctx context.Context, enabledUntil *time.Time) {
if enabledUntil == r.enabledUntil {
// Nothing to do.
return
}
r.enabledUntil = enabledUntil
log.FromContext(ctx).Info("maintenance mode state change", "enabledUntil", enabledUntil)
}
func (r *MaintenanceReconciler) SetupWithManager(mgr ctrl.Manager) error {
return ctrl.NewControllerManagedBy(mgr).
Named("maintenance").
For(&corev1.ConfigMap{}).
Complete(r)
}