Replace VerifyingPreview with Pause

README.md

@@ -67,9 +67,9 @@ In addition to managing replica sets, the Argo Rollouts will modify `Service` re
         * The active service is not serving any traffic to any replica sets created by this rollout. 
         * The active service's selector already points at the new replica set. 
     1. Verify if the preview service is serving traffic to the new replica set.
-        * Otherwise, set the preview service's selector to the new replica set and set the `verifyingPreview` flag in the rollout status to true.
-1. Check if the `verifyingPreview` flag is set to true.
-    * Do not progress until `verifyingPreview` is unset or set to false.
+        * Otherwise, set the preview service's selector to the new replica set and set the `paused` flag and `pausedStartedAt` field in the rollout status to true.
+1. Check if the `paused` flag is set to true.
+    * Do not progress until `paused` is set to false.
 1. Reconcile if the active service is serving traffic to the new replica set
     1. Verify if the active service is serving traffic to the new replica set.
         * Set the active service's selector to the new replica set

controller/bluegreen.go

@@ -5,7 +5,6 @@ import (
 
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
-	patchtypes "k8s.io/apimachinery/pkg/types"
 	"k8s.io/kubernetes/pkg/controller"
 
 	"github.com/argoproj/argo-rollouts/pkg/apis/rollouts/v1alpha1"
@@ -16,14 +15,6 @@ import (
 	replicasetutil "github.com/argoproj/argo-rollouts/utils/replicaset"
 )
 
-const (
-	verifyingPreviewPatch = `{
-	"status": {
-		"verifyingPreview": true
-	}
-}`
-)
-
 // rolloutBlueGreen implements the logic for rolling a new replica set.
 func (c *Controller) rolloutBlueGreen(r *v1alpha1.Rollout, rsList []*appsv1.ReplicaSet) error {
 	logCtx := logutil.WithRollout(r)
@@ -45,7 +36,7 @@ func (c *Controller) rolloutBlueGreen(r *v1alpha1.Rollout, rsList []*appsv1.Repl
 	}
 	if scaledUp {
 		logCtx.Infof("Not finished reconciling new ReplicaSet '%s'", newRS.Name)
-		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
+		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, false)
 	}
 
 	if previewSvc != nil {
@@ -56,24 +47,27 @@ func (c *Controller) rolloutBlueGreen(r *v1alpha1.Rollout, rsList []*appsv1.Repl
 		}
 		if switchPreviewSvc {
 			logCtx.Infof("Not finished reconciling preview service' %s'", previewSvc.Name)
-			return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
-		}
-		logCtx.Info("Reconciling verifying preview service")
-		verfyingPreview := c.reconcileVerifyingPreview(activeSvc, r)
-		if verfyingPreview {
-			logCtx.Info("Not finished reconciling verifying preview service")
-			return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
+			return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, true)
 		}
 	}
+
+	logCtx.Info("Reconciling pause before switching active service")
+	pauseBeforeSwitchActive := c.reconcileBlueGreenPause(activeSvc, r)
+	if pauseBeforeSwitchActive {
+		logCtx.Info("Not finished reconciling pause before switching active service")
+		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, true)
+	}
+
 	logCtx.Infof("Reconciling active service '%s'", activeSvc.Name)
 	switchActiveSvc, err := c.reconcileActiveService(r, newRS, previewSvc, activeSvc)
 	if err != nil {
 		return err
 	}
 	if switchActiveSvc {
 		logCtx.Infof("Not Finished reconciling active service '%s'", activeSvc.Name)
-		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
+		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, false)
 	}
+
 	// Scale down, if we can.
 	logCtx.Info("Reconciling old replica sets")
 	scaledDown, err := c.reconcileOldReplicaSets(allRSs, controller.FilterActiveReplicaSets(oldRSs), newRS, r)
@@ -82,31 +76,28 @@ func (c *Controller) rolloutBlueGreen(r *v1alpha1.Rollout, rsList []*appsv1.Repl
 	}
 	if scaledDown {
 		logCtx.Info("Not finished reconciling old replica sets")
-		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
+		return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, false)
 	}
+
 	logCtx.Infof("Confirming rollout is complete")
 	if conditions.RolloutComplete(r, &r.Status) {
 		logCtx.Info("Cleaning up old replicasets")
 		if err := c.cleanupRollouts(oldRSs, r); err != nil {
 			return err
 		}
 	}
-	return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r)
+	return c.syncRolloutStatusBlueGreen(allRSs, newRS, previewSvc, activeSvc, r, false)
 }
 
-func (c *Controller) reconcileVerifyingPreview(activeSvc *corev1.Service, rollout *v1alpha1.Rollout) bool {
+func (c *Controller) reconcileBlueGreenPause(activeSvc *corev1.Service, rollout *v1alpha1.Rollout) bool {
 	if rollout.Spec.Strategy.BlueGreenStrategy.PreviewService == "" {
 		return false
 	}
 	if _, ok := activeSvc.Spec.Selector[v1alpha1.DefaultRolloutUniqueLabelKey]; !ok {
 		return false
 	}
 
-	if rollout.Status.VerifyingPreview == nil {
-		return false
-	}
-
-	return *rollout.Status.VerifyingPreview
+	return rollout.Spec.Paused && rollout.Status.PauseStartTime != nil
 }
 
 // scaleDownOldReplicaSetsForBlueGreen scales down old replica sets when rollout strategy is "Blue Green".
@@ -140,13 +131,7 @@ func (c *Controller) scaleDownOldReplicaSetsForBlueGreen(allRSs []*appsv1.Replic
 	return totalScaledDown, nil
 }
 
-func (c *Controller) setVerifyingPreview(r *v1alpha1.Rollout) error {
-	logutil.WithRollout(r).Infof("Patching setVerifyingPreview to true")
-	_, err := c.rolloutsclientset.ArgoprojV1alpha1().Rollouts(r.Namespace).Patch(r.Name, patchtypes.MergePatchType, []byte(verifyingPreviewPatch))
-	return err
-}
-
-func (c *Controller) syncRolloutStatusBlueGreen(allRSs []*appsv1.ReplicaSet, newRS *appsv1.ReplicaSet, previewSvc *corev1.Service, activeSvc *corev1.Service, r *v1alpha1.Rollout) error {
+func (c *Controller) syncRolloutStatusBlueGreen(allRSs []*appsv1.ReplicaSet, newRS *appsv1.ReplicaSet, previewSvc *corev1.Service, activeSvc *corev1.Service, r *v1alpha1.Rollout, addPause bool) error {
 	newStatus := c.calculateBaseStatus(allRSs, newRS, r)
 	previewSelector, ok := c.getRolloutSelectorLabel(previewSvc)
 	if !ok {
@@ -170,9 +155,10 @@ func (c *Controller) syncRolloutStatusBlueGreen(allRSs []*appsv1.ReplicaSet, new
 		conditions.SetRolloutCondition(&prevStatus, *noAvailability)
 	}
 	newStatus.Conditions = prevStatus.Conditions
-	newStatus.VerifyingPreview = r.Status.VerifyingPreview
 
-	return c.persistRolloutStatus(r, &newStatus, nil)
+	pauseStartTime, paused := calculatePauseStatus(r, addPause)
+	newStatus.PauseStartTime = pauseStartTime
+	return c.persistRolloutStatus(r, &newStatus, &paused)
 }
 
 // Should run only on scaling events and not during the normal rollout process.