fix deployment replicas syncer in case that status.replicas haven't been collected

Signed-off-by: chaosi-zju <chaosi@zju.edu.cn>

pkg/controllers/deploymentreplicassyncer/deployment_replicas_syncer_controller.go

@@ -18,7 +18,8 @@ package deploymentreplicassyncer
 
 import (
 	"context"
-	"fmt"
+	"encoding/json"
+	"time"
 
 	appsv1 "k8s.io/api/apps/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
@@ -38,6 +39,8 @@ import (
 const (
 	// ControllerName is the controller name that will be used when reporting events.
 	ControllerName = "deployment-replicas-syncer"
+
+	waitDeploymentStatusInterval = 1 * time.Second
 )
 
 // DeploymentReplicasSyncer is to sync deployment replicas from status field to spec field.
@@ -98,6 +101,7 @@ func (r *DeploymentReplicasSyncer) Reconcile(ctx context.Context, req controller
 	binding := &workv1alpha2.ResourceBinding{}
 	bindingName := names.GenerateBindingName(util.DeploymentKind, req.Name)
 
+	// 1. get latest binding
 	if err := r.Client.Get(ctx, client.ObjectKey{Namespace: req.Namespace, Name: bindingName}, binding); err != nil {
 		if apierrors.IsNotFound(err) {
 			klog.Infof("no need to update deployment replicas for binding not found")
@@ -106,11 +110,12 @@ func (r *DeploymentReplicasSyncer) Reconcile(ctx context.Context, req controller
 		return controllerruntime.Result{}, err
 	}
 
-	// if it is not divided schedule type, no need to update replicas
+	// 2. if it is not divided schedule type, no need to update replicas
 	if binding.Spec.Placement.ReplicaSchedulingType() != policyv1alpha1.ReplicaSchedulingTypeDivided {
 		return controllerruntime.Result{}, nil
 	}
 
+	// 3. get latest deployment
 	if err := r.Client.Get(ctx, req.NamespacedName, deployment); err != nil {
 		if apierrors.IsNotFound(err) {
 			klog.Infof("no need to update deployment replicas for deployment not found")
@@ -119,39 +124,18 @@ func (r *DeploymentReplicasSyncer) Reconcile(ctx context.Context, req controller
 		return controllerruntime.Result{}, err
 	}
 
-	// if replicas in spec already the same as in status, no need to update replicas
+	// 4. if replicas in spec already the same as in status, no need to update replicas
 	if deployment.Spec.Replicas != nil && *deployment.Spec.Replicas == deployment.Status.Replicas {
 		klog.Infof("replicas in spec field (%d) already equal to in status field (%d)", *deployment.Spec.Replicas, deployment.Status.Replicas)
 		return controllerruntime.Result{}, nil
 	}
 
-	// make sure the replicas change in deployment.spec can sync to binding.spec, otherwise retry
-	if deployment.Spec.Replicas == nil || *deployment.Spec.Replicas != binding.Spec.Replicas {
-		klog.V(4).Infof("wait until replicas of binding (%d) equal to replicas of deployment (%d)",
-			binding.Spec.Replicas, *deployment.Spec.Replicas)
-		return controllerruntime.Result{}, fmt.Errorf("retry to wait replicas change sync to binding")
+	// 5. judge the deployment modification in spec has taken effect and its status has been collected, otherwise retry.
+	if !isDeploymentStatusCollected(deployment, binding) {
+		return controllerruntime.Result{RequeueAfter: waitDeploymentStatusInterval}, nil
 	}
 
-	// make sure the scheduler observed generation equal to generation in binding, otherwise retry
-	if binding.Generation != binding.Status.SchedulerObservedGeneration {
-		klog.V(4).Infof("wait until scheduler observed generation (%d) equal to generation in binding (%d)",
-			binding.Status.SchedulerObservedGeneration, binding.Generation)
-		return controllerruntime.Result{}, fmt.Errorf("retry to wait scheduler observed generation")
-	}
-
-	if len(binding.Status.AggregatedStatus) != len(binding.Spec.Clusters) {
-		klog.V(4).Infof("wait until all clusters status collected, got: %d, expected: %d",
-			len(binding.Status.AggregatedStatus), len(binding.Spec.Clusters))
-		return controllerruntime.Result{}, fmt.Errorf("retry to wait status in binding collected")
-	}
-	for _, status := range binding.Status.AggregatedStatus {
-		if status.Status == nil {
-			klog.V(4).Infof("wait until aggregated status of cluster %s collected", status.ClusterName)
-			return controllerruntime.Result{}, fmt.Errorf("retry to wait status in binding collected")
-		}
-	}
-
-	// update replicas
+	// 6. update spec replicas with status replicas
 	oldReplicas := *deployment.Spec.Replicas
 	deployment.Spec.Replicas = &deployment.Status.Replicas
 	if err := r.Client.Update(ctx, deployment); err != nil {
@@ -159,8 +143,64 @@ func (r *DeploymentReplicasSyncer) Reconcile(ctx context.Context, req controller
 		return controllerruntime.Result{}, err
 	}
 
-	klog.Infof("successfully udpate deployment (%s/%s) replicas from %d to %d", deployment.Namespace,
-		deployment.Namespace, oldReplicas, deployment.Status.Replicas)
+	klog.Infof("successfully update deployment (%s/%s) replicas from %d to %d", deployment.Namespace,
+		deployment.Name, oldReplicas, deployment.Status.Replicas)
 
 	return controllerruntime.Result{}, nil
 }
+
+// isDeploymentStatusCollected judge whether deployment modification in spec has taken effect and its status has been collected.
+func isDeploymentStatusCollected(deployment *appsv1.Deployment, binding *workv1alpha2.ResourceBinding) bool {
+	// make sure the replicas change in deployment.spec can sync to binding.spec, otherwise retry
+	if deployment.Spec.Replicas == nil || *deployment.Spec.Replicas != binding.Spec.Replicas {
+		klog.V(4).Infof("wait until replicas of binding (%d) equal to replicas of deployment (%d)",
+			binding.Spec.Replicas, *deployment.Spec.Replicas)
+		return false
+	}
+
+	// make sure the scheduler observed generation equal to generation in binding, otherwise retry
+	if binding.Generation != binding.Status.SchedulerObservedGeneration {
+		klog.V(4).Infof("wait until scheduler observed generation (%d) equal to generation in binding (%d)",
+			binding.Status.SchedulerObservedGeneration, binding.Generation)
+		return false
+	}
+
+	// make sure the number of aggregated status in binding is as expected.
+	if len(binding.Status.AggregatedStatus) != len(binding.Spec.Clusters) {
+		klog.V(4).Infof("wait until all clusters status collected, got: %d, expected: %d",
+			len(binding.Status.AggregatedStatus), len(binding.Spec.Clusters))
+		return false
+	}
+
+	// make sure the status.replicas in binding has been collected from work to binding.
+	bindingStatusSumReplicas := int32(0)
+	for _, status := range binding.Status.AggregatedStatus {
+		if status.Status == nil {
+			klog.V(4).Infof("wait until aggregated status of cluster %s collected", status.ClusterName)
+			return false
+		}
+		itemStatus := &appsv1.DeploymentStatus{}
+		if err := json.Unmarshal(status.Status.Raw, itemStatus); err != nil {
+			klog.Errorf("unmarshal status.raw of cluster %s in binding failed: %+v", status.ClusterName, err)
+			return false
+		}
+		// if member cluster deployment is controlled by hpa, its status.replicas must > 0 (since hpa.minReplicas > 0),
+		// so, if its status replicas is 0, means the status haven't been collected from member cluster, and needs waiting.
+		if itemStatus.Replicas <= 0 {
+			klog.V(4).Infof("wait until aggregated status replicas of cluster %s collected", status.ClusterName)
+			return false
+		}
+		bindingStatusSumReplicas += itemStatus.Replicas
+	}
+
+	// make sure the latest collected status.replicas is synced from binding to template.
+	// e.g: user set deployment.spec.replicas = 2, then sum replicas in binding.status becomes 2, however, if now
+	// deployment.status.replicas is still 1, we shouldn't update spec.replicas to 1 until status.replicas becomes 2.
+	if deployment.Status.Replicas != bindingStatusSumReplicas {
+		klog.V(4).Infof("wait until deployment status replicas (%d) equal to binding status replicas (%d)",
+			deployment.Status.Replicas, bindingStatusSumReplicas)
+		return false
+	}
+
+	return true
+}

pkg/resourceinterpreter/default/native/reflectstatus.go

@@ -17,6 +17,7 @@ limitations under the License.
 package native
 
 import (
+	"bytes"
 	"fmt"
 
 	appsv1 "k8s.io/api/apps/v1"
@@ -74,7 +75,18 @@ func reflectDeploymentStatus(object *unstructured.Unstructured) (*runtime.RawExt
 		AvailableReplicas:   deploymentStatus.AvailableReplicas,
 		UnavailableReplicas: deploymentStatus.UnavailableReplicas,
 	}
-	return helper.BuildStatusRawExtension(grabStatus)
+
+	grabStatusRaw, err := helper.BuildStatusRawExtension(grabStatus)
+	if err != nil {
+		return nil, err
+	}
+
+	// if status is empty struct, it actually means status haven't been collected from member cluster.
+	if bytes.Equal(grabStatusRaw.Raw, []byte("{}")) {
+		return nil, nil
+	}
+
+	return grabStatusRaw, nil
 }
 
 func reflectServiceStatus(object *unstructured.Unstructured) (*runtime.RawExtension, error) {