diff options
Diffstat (limited to 'vendor/k8s.io/client-go/tools/cache/listwatch.go')
-rw-r--r-- | vendor/k8s.io/client-go/tools/cache/listwatch.go | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/vendor/k8s.io/client-go/tools/cache/listwatch.go b/vendor/k8s.io/client-go/tools/cache/listwatch.go new file mode 100644 index 000000000..af01d4745 --- /dev/null +++ b/vendor/k8s.io/client-go/tools/cache/listwatch.go @@ -0,0 +1,162 @@ +/* +Copyright 2015 The Kubernetes 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 cache + +import ( + "time" + + "k8s.io/apimachinery/pkg/api/meta" + metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" + "k8s.io/apimachinery/pkg/fields" + "k8s.io/apimachinery/pkg/runtime" + "k8s.io/apimachinery/pkg/watch" + restclient "k8s.io/client-go/rest" +) + +// ListerWatcher is any object that knows how to perform an initial list and start a watch on a resource. +type ListerWatcher interface { + // List should return a list type object; the Items field will be extracted, and the + // ResourceVersion field will be used to start the watch in the right place. + List(options metav1.ListOptions) (runtime.Object, error) + // Watch should begin a watch at the specified version. + Watch(options metav1.ListOptions) (watch.Interface, error) +} + +// ListFunc knows how to list resources +type ListFunc func(options metav1.ListOptions) (runtime.Object, error) + +// WatchFunc knows how to watch resources +type WatchFunc func(options metav1.ListOptions) (watch.Interface, error) + +// ListWatch knows how to list and watch a set of apiserver resources. It satisfies the ListerWatcher interface. +// It is a convenience function for users of NewReflector, etc. +// ListFunc and WatchFunc must not be nil +type ListWatch struct { + ListFunc ListFunc + WatchFunc WatchFunc +} + +// Getter interface knows how to access Get method from RESTClient. +type Getter interface { + Get() *restclient.Request +} + +// NewListWatchFromClient creates a new ListWatch from the specified client, resource, namespace and field selector. +func NewListWatchFromClient(c Getter, resource string, namespace string, fieldSelector fields.Selector) *ListWatch { + listFunc := func(options metav1.ListOptions) (runtime.Object, error) { + return c.Get(). + Namespace(namespace). + Resource(resource). + VersionedParams(&options, metav1.ParameterCodec). + FieldsSelectorParam(fieldSelector). + Do(). + Get() + } + watchFunc := func(options metav1.ListOptions) (watch.Interface, error) { + options.Watch = true + return c.Get(). + Namespace(namespace). + Resource(resource). + VersionedParams(&options, metav1.ParameterCodec). + FieldsSelectorParam(fieldSelector). + Watch() + } + return &ListWatch{ListFunc: listFunc, WatchFunc: watchFunc} +} + +func timeoutFromListOptions(options metav1.ListOptions) time.Duration { + if options.TimeoutSeconds != nil { + return time.Duration(*options.TimeoutSeconds) * time.Second + } + return 0 +} + +// List a set of apiserver resources +func (lw *ListWatch) List(options metav1.ListOptions) (runtime.Object, error) { + return lw.ListFunc(options) +} + +// Watch a set of apiserver resources +func (lw *ListWatch) Watch(options metav1.ListOptions) (watch.Interface, error) { + return lw.WatchFunc(options) +} + +// TODO: check for watch expired error and retry watch from latest point? Same issue exists for Until. +func ListWatchUntil(timeout time.Duration, lw ListerWatcher, conditions ...watch.ConditionFunc) (*watch.Event, error) { + if len(conditions) == 0 { + return nil, nil + } + + list, err := lw.List(metav1.ListOptions{}) + if err != nil { + return nil, err + } + initialItems, err := meta.ExtractList(list) + if err != nil { + return nil, err + } + + // use the initial items as simulated "adds" + var lastEvent *watch.Event + currIndex := 0 + passedConditions := 0 + for _, condition := range conditions { + // check the next condition against the previous event and short circuit waiting for the next watch + if lastEvent != nil { + done, err := condition(*lastEvent) + if err != nil { + return lastEvent, err + } + if done { + passedConditions = passedConditions + 1 + continue + } + } + + ConditionSucceeded: + for currIndex < len(initialItems) { + lastEvent = &watch.Event{Type: watch.Added, Object: initialItems[currIndex]} + currIndex++ + + done, err := condition(*lastEvent) + if err != nil { + return lastEvent, err + } + if done { + passedConditions = passedConditions + 1 + break ConditionSucceeded + } + } + } + if passedConditions == len(conditions) { + return lastEvent, nil + } + remainingConditions := conditions[passedConditions:] + + metaObj, err := meta.ListAccessor(list) + if err != nil { + return nil, err + } + currResourceVersion := metaObj.GetResourceVersion() + + watchInterface, err := lw.Watch(metav1.ListOptions{ResourceVersion: currResourceVersion}) + if err != nil { + return nil, err + } + + return watch.Until(timeout, watchInterface, remainingConditions...) +} |