| // Copyright Istio Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package configmapwatcher |
| |
| import ( |
| "fmt" |
| "time" |
| ) |
| |
| import ( |
| "go.uber.org/atomic" |
| "istio.io/pkg/log" |
| v1 "k8s.io/api/core/v1" |
| "k8s.io/apimachinery/pkg/api/errors" |
| metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" |
| "k8s.io/apimachinery/pkg/fields" |
| "k8s.io/apimachinery/pkg/types" |
| "k8s.io/client-go/informers" |
| informersv1 "k8s.io/client-go/informers/core/v1" |
| "k8s.io/client-go/tools/cache" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go-pixiu/pkg/kube" |
| "github.com/apache/dubbo-go-pixiu/pkg/kube/controllers" |
| ) |
| |
| // Controller watches a ConfigMap and calls the given callback when the ConfigMap changes. |
| // The ConfigMap is passed to the callback, or nil if it doesn't exist. |
| type Controller struct { |
| informer informersv1.ConfigMapInformer |
| queue controllers.Queue |
| |
| configMapNamespace string |
| configMapName string |
| callback func(*v1.ConfigMap) |
| |
| hasSynced atomic.Bool |
| } |
| |
| // NewController returns a new ConfigMap watcher controller. |
| func NewController(client kube.Client, namespace, name string, callback func(*v1.ConfigMap)) *Controller { |
| c := &Controller{ |
| configMapNamespace: namespace, |
| configMapName: name, |
| callback: callback, |
| } |
| |
| // Although using a separate informer factory isn't ideal, |
| // this does so to limit watching to only the specified ConfigMap. |
| c.informer = informers.NewSharedInformerFactoryWithOptions(client.Kube(), 12*time.Hour, |
| informers.WithNamespace(namespace), |
| informers.WithTweakListOptions(func(listOptions *metav1.ListOptions) { |
| listOptions.FieldSelector = fields.OneTermEqualSelector(metav1.ObjectNameField, name).String() |
| })). |
| Core().V1().ConfigMaps() |
| |
| c.queue = controllers.NewQueue("configmap "+name, controllers.WithReconciler(c.processItem)) |
| c.informer.Informer().AddEventHandler(controllers.FilteredObjectSpecHandler(c.queue.AddObject, func(o controllers.Object) bool { |
| // Filter out configmaps |
| return o.GetName() == name && o.GetNamespace() == namespace |
| })) |
| |
| return c |
| } |
| |
| func (c *Controller) Run(stop <-chan struct{}) { |
| go c.informer.Informer().Run(stop) |
| if !cache.WaitForCacheSync(stop, c.informer.Informer().HasSynced) { |
| log.Error("failed to wait for cache sync") |
| return |
| } |
| c.queue.Run(stop) |
| } |
| |
| // HasSynced returns whether the underlying cache has synced and the callback has been called at least once. |
| func (c *Controller) HasSynced() bool { |
| return c.queue.HasSynced() |
| } |
| |
| func (c *Controller) processItem(name types.NamespacedName) error { |
| cm, err := c.informer.Lister().ConfigMaps(c.configMapNamespace).Get(c.configMapName) |
| if err != nil { |
| if !errors.IsNotFound(err) { |
| return fmt.Errorf("error fetching object %s error: %v", c.configMapName, err) |
| } |
| cm = nil |
| } |
| c.callback(cm) |
| |
| c.hasSynced.Store(true) |
| return nil |
| } |