Add a workqueue abstraction for processing objects pulled from informers

Signed-off-by: Kevin Klues <[email protected]>

Author: klueska

pkg/workqueue/workqueue.go

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2025 NVIDIA CORPORATION.  All rights reserved.
+ *
+ * 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 workqueue
+
+import (
+	"fmt"
+
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/util/workqueue"
+	"k8s.io/klog/v2"
+)
+
+type WorkQueue struct {
+	queue workqueue.TypedRateLimitingInterface[any]
+}
+
+type WorkItem struct {
+	Object   any
+	Callback func(obj any) error
+}
+
+func DefaultControllerRateLimiter() workqueue.TypedRateLimiter[any] {
+	return workqueue.DefaultTypedControllerRateLimiter[any]()
+}
+
+func New(r workqueue.TypedRateLimiter[any]) *WorkQueue {
+	queue := workqueue.NewTypedRateLimitingQueue(r)
+	return &WorkQueue{queue}
+}
+
+func (q *WorkQueue) Run(done <-chan struct{}) {
+	go func() {
+		<-done
+		q.queue.ShutDown()
+	}()
+	for {
+		select {
+		case <-done:
+			return
+		default:
+			q.processNextWorkItem()
+		}
+	}
+}
+
+func (q *WorkQueue) Enqueue(obj any, callback func(obj any) error) {
+	runtimeObj, ok := obj.(runtime.Object)
+	if !ok {
+		klog.Warningf("unexpected object type %T: runtime.Object required", obj)
+		return
+	}
+
+	workItem := &WorkItem{
+		Object:   runtimeObj.DeepCopyObject(),
+		Callback: callback,
+	}
+
+	q.queue.AddRateLimited(workItem)
+}
+
+func (q *WorkQueue) processNextWorkItem() {
+	item, shutdown := q.queue.Get()
+	if shutdown {
+		return
+	}
+	defer q.queue.Done(item)
+
+	workItem, ok := item.(*WorkItem)
+	if !ok {
+		klog.Errorf("Unexpected item in queue: %v", item)
+		return
+	}
+
+	err := q.reconcile(workItem)
+	if err != nil {
+		klog.Errorf("Failed to reconcile work item %v: %v", workItem.Object, err)
+		q.queue.AddRateLimited(workItem)
+	} else {
+		q.queue.Forget(workItem)
+	}
+}
+
+func (q *WorkQueue) reconcile(workItem *WorkItem) error {
+	if workItem.Callback == nil {
+		return fmt.Errorf("no callback to process work item: %+v", workItem)
+	}
+	return workItem.Callback(workItem.Object)
+}