l-43

controllers/app_controller.go

@@ -50,8 +50,17 @@ type AppReconciler struct {
 func (r *AppReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
 	_ = log.FromContext(ctx)
 
-	// TODO(user): your logic here
+	// 获取对象的惯例写法
+	app := new(demov1.App)
 
+	// Get（） 会调用实现了 Reader Interface 的对象。
+	// 找到了实现的对象为  `delegatingReader` ，它只实现了 Reader 接口
+	if err := r.Client.Get(ctx, req.NamespacedName, app); err != nil {
+		return ctrl.Result{}, client.IgnoreNotFound(err)
+	}
+
+	// create() 会调用实现了 Writer Interface 的对象
+	//r.Client.Create()
 	return ctrl.Result{}, nil
 }
 

vendor/sigs.k8s.io/controller-runtime/pkg/client/split.go

@@ -120,6 +120,7 @@ func (d *delegatingReader) shouldBypassCache(obj runtime.Object) (bool, error) {
 	return false, nil
 }
 
+// 使用 cache 访问
 // Get retrieves an obj for a given object key from the Kubernetes Cluster.
 func (d *delegatingReader) Get(ctx context.Context, key ObjectKey, obj Object, opts ...GetOption) error {
 	if isUncached, err := d.shouldBypassCache(obj); err != nil {
@@ -130,6 +131,7 @@ func (d *delegatingReader) Get(ctx context.Context, key ObjectKey, obj Object, o
 	return d.CacheReader.Get(ctx, key, obj, opts...)
 }
 
+// 使用 cache 访问
 // List retrieves list of objects for a given namespace and list options.
 func (d *delegatingReader) List(ctx context.Context, list ObjectList, opts ...ListOption) error {
 	if isUncached, err := d.shouldBypassCache(list); err != nil {

vendor/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go

@@ -118,6 +118,7 @@ func (c *Controller) Reconcile(ctx context.Context, req reconcile.Request) (_ re
 			panic(r)
 		}
 	}()
+	// 去调用我们的 reconcile。这里之后是 interface。但是Do这个字段中的 Reconcile 是我们之前传进来的。
 	return c.Do.Reconcile(ctx, req)
 }
 
@@ -161,11 +162,13 @@ func (c *Controller) Start(ctx context.Context) error {
 		return errors.New("controller was started more than once. This is likely to be caused by being added to a manager multiple times")
 	}
 
+	// 初始化监控相关的信息
 	c.initMetrics()
 
 	// Set the internal context.
 	c.ctx = ctx
 
+	// 创建了一个限速队列
 	c.Queue = c.MakeQueue()
 	go func() {
 		<-ctx.Done()
@@ -179,6 +182,7 @@ func (c *Controller) Start(ctx context.Context) error {
 		// TODO(pwittrock): Reconsider HandleCrash
 		defer utilruntime.HandleCrash()
 
+		// 启动所有的事件源
 		// NB(directxman12): launch the sources *before* trying to wait for the
 		// caches to sync so that they have a chance to register their intendeded
 		// caches.
@@ -193,6 +197,7 @@ func (c *Controller) Start(ctx context.Context) error {
 		// Start the SharedIndexInformer factories to begin populating the SharedIndexInformer caches
 		c.LogConstructor(nil).Info("Starting Controller")
 
+		// 等待一次同步完成
 		for _, watch := range c.startWatches {
 			syncingSource, ok := watch.src.(source.SyncingSource)
 			if !ok {
@@ -218,6 +223,7 @@ func (c *Controller) Start(ctx context.Context) error {
 			}
 		}
 
+		// 完成一次同步后，清空所有源
 		// All the watches have been started, we can reset the local slice.
 		//
 		// We should never hold watches more than necessary, each watch source can hold a backing cache,
@@ -230,6 +236,7 @@ func (c *Controller) Start(ctx context.Context) error {
 		for i := 0; i < c.MaxConcurrentReconciles; i++ {
 			go func() {
 				defer wg.Done()
+				// 不断的从队列中读取任务
 				// Run a worker thread that just dequeues items, processes them, and marks them done.
 				// It enforces that the reconcileHandler is never invoked concurrently with the same object.
 				for c.processNextWorkItem(ctx) {
@@ -254,6 +261,7 @@ func (c *Controller) Start(ctx context.Context) error {
 // processNextWorkItem will read a single work item off the workqueue and
 // attempt to process it, by calling the reconcileHandler.
 func (c *Controller) processNextWorkItem(ctx context.Context) bool {
+	// 获取事件
 	obj, shutdown := c.Queue.Get()
 	if shutdown {
 		// Stop working
@@ -268,9 +276,11 @@ func (c *Controller) processNextWorkItem(ctx context.Context) bool {
 	// period.
 	defer c.Queue.Done(obj)
 
+	// 加入一些监控可视化的信息
 	ctrlmetrics.ActiveWorkers.WithLabelValues(c.Name).Add(1)
 	defer ctrlmetrics.ActiveWorkers.WithLabelValues(c.Name).Add(-1)
 
+	// 去调用我们的 reconcile
 	c.reconcileHandler(ctx, obj)
 	return true
 }
@@ -293,6 +303,7 @@ func (c *Controller) initMetrics() {
 }
 
 func (c *Controller) reconcileHandler(ctx context.Context, obj interface{}) {
+	// 计时
 	// Update metrics after processing each item
 	reconcileStartTS := time.Now()
 	defer func() {
@@ -302,6 +313,7 @@ func (c *Controller) reconcileHandler(ctx context.Context, obj interface{}) {
 	// Make sure that the object is a valid request.
 	req, ok := obj.(reconcile.Request)
 	if !ok {
+		// 异常，在队列中删掉这个对象
 		// As the item in the workqueue is actually invalid, we call
 		// Forget here else we'd go into a loop of attempting to
 		// process a work item that is invalid.
@@ -316,16 +328,22 @@ func (c *Controller) reconcileHandler(ctx context.Context, obj interface{}) {
 	log = log.WithValues("reconcileID", uuid.NewUUID())
 	ctx = logf.IntoContext(ctx, log)
 
+	// 去调用我们的 reconcile
 	// RunInformersAndControllers the syncHandler, passing it the Namespace/Name string of the
 	// resource to be synced.
 	result, err := c.Reconcile(ctx, req)
+	// 处理我们的 reconcile 返回值的地方
 	switch {
 	case err != nil:
+		// 如果报错，则重新加入队列，并记录监控信息，并记录错误日志
+		// 如果我们返回了err，同时设定了重新入队的时间，那么，这个时间不会生效。
 		c.Queue.AddRateLimited(req)
 		ctrlmetrics.ReconcileErrors.WithLabelValues(c.Name).Inc()
 		ctrlmetrics.ReconcileTotal.WithLabelValues(c.Name, labelError).Inc()
 		log.Error(err, "Reconciler error")
 	case result.RequeueAfter > 0:
+		// 如果 rsults 中的 RequeueAfter，也就是设置等待一定使时间之后，再次入队。
+		// 那么，会删掉从队列中删掉事件，等待设定的时间后再次入队。并更新监控信息
 		// The result.RequeueAfter request will be lost, if it is returned
 		// along with a non-nil error. But this is intended as
 		// We need to drive to stable reconcile loops before queuing due
@@ -334,9 +352,11 @@ func (c *Controller) reconcileHandler(ctx context.Context, obj interface{}) {
 		c.Queue.AddAfter(req, result.RequeueAfter)
 		ctrlmetrics.ReconcileTotal.WithLabelValues(c.Name, labelRequeueAfter).Inc()
 	case result.Requeue:
+		// 直接设置重新入队，会立刻重新入队，并更新监控信息。
 		c.Queue.AddRateLimited(req)
 		ctrlmetrics.ReconcileTotal.WithLabelValues(c.Name, labelRequeue).Inc()
 	default:
+		// 除此之外，从队列中删除事件。并更新监控信息
 		// Finally, if no error occurs we Forget this item so it does not
 		// get queued again until another change happens.
 		c.Queue.Forget(obj)