simplify ScalingReplicaSet event building in the deployment controller

Author: atiratree

pkg/controller/deployment/sync.go

@@ -340,15 +340,12 @@ func (dc *DeploymentController) scale(ctx context.Context, deployment *apps.Depl
 // drives what happens in case we are trying to scale replica sets of the same size.
 // In such a case when scaling up, we should scale up newer replica sets first, and
 // when scaling down, we should scale down older replica sets first.
-var scalingOperation string
 switch {
 case deploymentReplicasToAdd > 0:
 sort.Sort(controller.ReplicaSetsBySizeNewer(allRSs))
-scalingOperation = "up"
 
 case deploymentReplicasToAdd < 0:
 sort.Sort(controller.ReplicaSetsBySizeOlder(allRSs))
-scalingOperation = "down"
 }
 
 // Iterate over all active replica sets and estimate proportions for each of them.
@@ -386,7 +383,7 @@ func (dc *DeploymentController) scale(ctx context.Context, deployment *apps.Depl
 }
 
 // TODO: Use transactions when we have them.
-if _, _, err := dc.scaleReplicaSet(ctx, rs, nameToSize[rs.Name], deployment, scalingOperation); err != nil {
+if _, _, err := dc.scaleReplicaSet(ctx, rs, nameToSize[rs.Name], deployment); err != nil {
 // Return as soon as we fail, the deployment is requeued
 return err
 }
@@ -400,17 +397,11 @@ func (dc *DeploymentController) scaleReplicaSetAndRecordEvent(ctx context.Contex
 if *(rs.Spec.Replicas) == newScale {
 return false, rs, nil
 }
-var scalingOperation string
-if *(rs.Spec.Replicas) < newScale {
-scalingOperation = "up"
-} else {
-scalingOperation = "down"
-}
-scaled, newRS, err := dc.scaleReplicaSet(ctx, rs, newScale, deployment, scalingOperation)
+scaled, newRS, err := dc.scaleReplicaSet(ctx, rs, newScale, deployment)
 return scaled, newRS, err
 }
 
-func (dc *DeploymentController) scaleReplicaSet(ctx context.Context, rs *apps.ReplicaSet, newScale int32, deployment *apps.Deployment, scalingOperation string) (bool, *apps.ReplicaSet, error) {
+func (dc *DeploymentController) scaleReplicaSet(ctx context.Context, rs *apps.ReplicaSet, newScale int32, deployment *apps.Deployment) (bool, *apps.ReplicaSet, error) {
 
 sizeNeedsUpdate := *(rs.Spec.Replicas) != newScale
 
@@ -425,6 +416,12 @@ func (dc *DeploymentController) scaleReplicaSet(ctx context.Context, rs *apps.Re
 deploymentutil.SetReplicasAnnotations(rsCopy, *(deployment.Spec.Replicas), *(deployment.Spec.Replicas)+deploymentutil.MaxSurge(*deployment))
 rs, err = dc.client.AppsV1().ReplicaSets(rsCopy.Namespace).Update(ctx, rsCopy, metav1.UpdateOptions{})
 if err == nil && sizeNeedsUpdate {
+var scalingOperation string
+if oldScale < newScale {
+scalingOperation = "up"
+} else {
+scalingOperation = "down"
+}
 scaled = true
 dc.eventRecorder.Eventf(deployment, v1.EventTypeNormal, "ScalingReplicaSet", "Scaled %s replica set %s from %d to %d", scalingOperation, rs.Name, oldScale, newScale)
 }