Implement finalising state

Set the canary status to finalising after routing the traffic back to the primary. Run one final loop before scaling the canary to zero so that the canary has a chance to process all inflight requests.

pkg/canary/status.go

@@ -211,6 +211,9 @@ func (c *Deployer) MakeStatusConditions(canaryStatus flaggerv1.CanaryStatus,
 	case flaggerv1.CanaryPhaseProgressing:
 		status = corev1.ConditionUnknown
 		message = "New revision detected, starting canary analysis."
+	case flaggerv1.CanaryPhaseFinalising:
+		status = corev1.ConditionUnknown
+		message = "Canary analysis completed, routing all traffic to primary."
 	case flaggerv1.CanaryPhaseSucceeded:
 		status = corev1.ConditionTrue
 		message = "Canary analysis completed successfully, promotion finished."

pkg/controller/scheduler.go

@@ -214,6 +214,26 @@ func (c *Controller) advanceCanary(name string, namespace string, skipLivenessCh
 		return
 	}
 
+	// scale canary to zero if analysis has succeeded
+	if cd.Status.Phase == flaggerv1.CanaryPhaseFinalising {
+		if err := c.deployer.Scale(cd, 0); err != nil {
+			c.recordEventWarningf(cd, "%v", err)
+			return
+		}
+
+		// set status to succeeded
+		if err := c.deployer.SetStatusPhase(cd, flaggerv1.CanaryPhaseSucceeded); err != nil {
+			c.recordEventWarningf(cd, "%v", err)
+			return
+		}
+		c.recorder.SetStatus(cd, flaggerv1.CanaryPhaseSucceeded)
+		c.runPostRolloutHooks(cd, flaggerv1.CanaryPhaseSucceeded)
+		c.recordEventInfof(cd, "Promotion completed! Scaling down %s.%s", cd.Spec.TargetRef.Name, cd.Namespace)
+		c.sendNotification(cd, "Canary analysis completed successfully, promotion finished.",
+			false, false)
+		return
+	}
+
 	// check if the number of failed checks reached the threshold
 	if cd.Status.Phase == flaggerv1.CanaryPhaseProgressing &&
 		(!retriable || cd.Status.FailedChecks >= cd.Spec.CanaryAnalysis.Threshold) {
@@ -319,31 +339,23 @@ func (c *Controller) advanceCanary(name string, namespace string, skipLivenessCh
 			return
 		}
 
-		// shutdown canary
+		// route all traffic to primary
 		if cd.Spec.CanaryAnalysis.Iterations < cd.Status.Iterations {
-			// route all traffic to the primary
-			if err := meshRouter.SetRoutes(cd, 100, 0); err != nil {
-				c.recordEventWarningf(cd, "%v", err)
-				return
-			}
-			c.recorder.SetWeight(cd, 100, 0)
-			c.recordEventInfof(cd, "Promotion completed! Scaling down %s.%s", cd.Spec.TargetRef.Name, cd.Namespace)
-
-			// canary scale to zero
-			if err := c.deployer.Scale(cd, 0); err != nil {
+			primaryWeight = 100
+			canaryWeight = 0
+			if err := meshRouter.SetRoutes(cd, primaryWeight, canaryWeight); err != nil {
 				c.recordEventWarningf(cd, "%v", err)
 				return
 			}
+			c.recorder.SetWeight(cd, primaryWeight, canaryWeight)
 
 			// update status phase
-			if err := c.deployer.SetStatusPhase(cd, flaggerv1.CanaryPhaseSucceeded); err != nil {
+			if err := c.deployer.SetStatusPhase(cd, flaggerv1.CanaryPhaseFinalising); err != nil {
 				c.recordEventWarningf(cd, "%v", err)
 				return
 			}
-			c.recorder.SetStatus(cd, flaggerv1.CanaryPhaseSucceeded)
-			c.runPostRolloutHooks(cd, flaggerv1.CanaryPhaseSucceeded)
-			c.sendNotification(cd, "Canary analysis completed successfully, promotion finished.",
-				false, false)
+
+			c.recordEventInfof(cd, "Routing all traffic to primary")
 			return
 		}
 
@@ -385,32 +397,23 @@ func (c *Controller) advanceCanary(name string, namespace string, skipLivenessCh
 			}
 		}
 	} else {
-		// route all traffic back to primary
+		// route all traffic to primary
 		primaryWeight = 100
 		canaryWeight = 0
 		if err := meshRouter.SetRoutes(cd, primaryWeight, canaryWeight); err != nil {
 			c.recordEventWarningf(cd, "%v", err)
 			return
 		}
-
 		c.recorder.SetWeight(cd, primaryWeight, canaryWeight)
-		c.recordEventInfof(cd, "Promotion completed! Scaling down %s.%s", cd.Spec.TargetRef.Name, cd.Namespace)
-
-		// shutdown canary
-		if err := c.deployer.Scale(cd, 0); err != nil {
-			c.recordEventWarningf(cd, "%v", err)
-			return
-		}
 
 		// update status phase
-		if err := c.deployer.SetStatusPhase(cd, flaggerv1.CanaryPhaseSucceeded); err != nil {
+		if err := c.deployer.SetStatusPhase(cd, flaggerv1.CanaryPhaseFinalising); err != nil {
 			c.recordEventWarningf(cd, "%v", err)
 			return
 		}
-		c.recorder.SetStatus(cd, flaggerv1.CanaryPhaseSucceeded)
-		c.runPostRolloutHooks(cd, flaggerv1.CanaryPhaseSucceeded)
-		c.sendNotification(cd, "Canary analysis completed successfully, promotion finished.",
-			false, false)
+
+		c.recordEventInfof(cd, "Routing all traffic to primary")
+		return
 	}
 }
 
@@ -462,7 +465,8 @@ func (c *Controller) shouldAdvance(cd *flaggerv1.Canary) (bool, error) {
 	if cd.Status.LastAppliedSpec == "" ||
 		cd.Status.Phase == flaggerv1.CanaryPhaseInitializing ||
 		cd.Status.Phase == flaggerv1.CanaryPhaseProgressing ||
-		cd.Status.Phase == flaggerv1.CanaryPhaseWaiting {
+		cd.Status.Phase == flaggerv1.CanaryPhaseWaiting ||
+		cd.Status.Phase == flaggerv1.CanaryPhaseFinalising {
 		return true, nil
 	}
 
@@ -485,7 +489,8 @@ func (c *Controller) shouldAdvance(cd *flaggerv1.Canary) (bool, error) {
 
 func (c *Controller) checkCanaryStatus(cd *flaggerv1.Canary, shouldAdvance bool) bool {
 	c.recorder.SetStatus(cd, cd.Status.Phase)
-	if cd.Status.Phase == flaggerv1.CanaryPhaseProgressing {
+	if cd.Status.Phase == flaggerv1.CanaryPhaseProgressing ||
+		cd.Status.Phase == flaggerv1.CanaryPhaseFinalising {
 		return true
 	}