move package

Signed-off-by: Roland.Ma <rolandma@yunify.com>

pkg/controller/utils/controller/basecontroller.go

@@ -0,0 +1,127 @@
+/*
+Copyright 2020 KubeSphere 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 controller
+
+import (
+	"fmt"
+	"time"
+
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/util/workqueue"
+	"k8s.io/klog"
+)
+
+// BaseController provides a Controller template for watching a primary resources that defined as CRD.
+type BaseController struct {
+	// Workers will wait informer caches to be synced
+	Synced []cache.InformerSynced
+	// Workqueue is a rate limited work queue.
+	Workqueue  workqueue.RateLimitingInterface
+	Handler    func(key string) error
+	MaxRetries int
+	Name       string
+}
+
+// Run will set up the event handlers for Primary resource, as well
+// as syncing informer caches and starting workers. It will block until stopCh
+// is closed, at which point it will shutdown the workqueue and wait for
+// workers to finish processing their current work items.
+func (c *BaseController) Run(threadiness int, stopCh <-chan struct{}) error {
+	defer utilruntime.HandleCrash()
+	defer c.Workqueue.ShutDown()
+
+	klog.Infof("Starting controller: %s", c.Name)
+	klog.Infof("Waiting for informer caches to sync for: %s", c.Name)
+	if ok := cache.WaitForCacheSync(stopCh, c.Synced...); !ok {
+		return fmt.Errorf("failed to wait for caches to sync for: %s", c.Name)
+	}
+
+	klog.Infof("Starting workers for: %s", c.Name)
+	for i := 0; i < threadiness; i++ {
+		go wait.Until(c.runWorker, time.Second, stopCh)
+	}
+
+	klog.Infof("Started workers for: %s", c.Name)
+	<-stopCh
+	klog.Infof("Shutting down workers for: %s", c.Name)
+	return nil
+}
+
+// Enqueue takes a primary resource and converts it into a namespace/name
+// string which is then put onto the work queue. This method should *not* be
+// passed resources of any type other than primary resource.
+func (c *BaseController) Enqueue(obj interface{}) {
+	var key string
+	var err error
+	if key, err = cache.MetaNamespaceKeyFunc(obj); err != nil {
+		utilruntime.HandleError(err)
+		return
+	}
+	c.Workqueue.Add(key)
+}
+
+// runWorker is a long-running function that will continually call the
+// processNextWorkItem function in order to read and process a message on the
+// workqueue.
+func (c *BaseController) runWorker() {
+	for c.processNextWorkItem() {
+	}
+}
+
+// processNextWorkItem will read a single work item off the workqueue and
+// attempt to process it, by calling the Handler.
+func (c *BaseController) processNextWorkItem() bool {
+	obj, shutdown := c.Workqueue.Get()
+
+	if shutdown {
+		return false
+	}
+	err := func(obj interface{}) error {
+		defer c.Workqueue.Done(obj)
+		var key string
+		var ok bool
+
+		if key, ok = obj.(string); !ok {
+			c.Workqueue.Forget(obj)
+			utilruntime.HandleError(fmt.Errorf("expected string in Workqueue but got %#v in %s", obj, c.Name))
+			return nil
+		}
+		if err := c.Handler(key); err != nil {
+			// Put the item back on the workqueue to handle any transient errors,
+			// when the max retries haven't reached or there is no retry times limit.
+			if c.MaxRetries == 0 || c.Workqueue.NumRequeues(key) < c.MaxRetries {
+				c.Workqueue.AddRateLimited(key)
+				return fmt.Errorf("error syncing '%s' in %s: %s, requeuing ", key, c.Name, err.Error())
+			}
+			klog.V(4).Infof("Dropping %s out of the queue in %s: %s", key, c.Name, err)
+			utilruntime.HandleError(err)
+			return nil
+		}
+		c.Workqueue.Forget(obj)
+		klog.Infof("Successfully Synced %s:%s in %s", "key", key, c.Name)
+		return nil
+	}(obj)
+
+	if err != nil {
+		utilruntime.HandleError(err)
+		return true
+	}
+
+	return true
+}