Assigner only checks the health status for routed components.

After #90, every babysitter retrieves routing information for
non-routed components. This means that the assigner is only
consulted to retrieve routing information for routed components.

.github/workflows/integration.yml

@@ -83,5 +83,6 @@ jobs:
 
     - name: Cleanup the echo app
       if: always()
-      run: ./cmd/weaver-gke/weaver-gke kill --force echo-${{env.VERSION}}
+      run: 
+        ./cmd/weaver-gke/weaver-gke kill --force echo-${{env.VERSION}} || true
 

internal/nanny/assigner/assigner.go

@@ -173,21 +173,27 @@ func (a *Assigner) registerApp(ctx context.Context, app string) error {
 
 // registerReplicaSet registers the provided Kubernetes ReplicaSet in the
 // appropriate app's state.
-func (a *Assigner) registerReplicaSet(ctx context.Context, rid *ReplicaSetId) error {
-	appName := rid.Config.Deployment.App.Name
-	_, _, err := a.applyAppState(ctx, appName, func(state *AppState) bool {
-		for _, existing := range state.ReplicaSetIds {
-			if proto.Equal(rid, existing) {
-				return false
+func (a *Assigner) registerReplicaSet(ctx context.Context, cfg *config.GKEConfig, replicaSet string, routed bool) (*ReplicaSetId, error) {
+	var rid *ReplicaSetId
+	_, _, err := a.applyAppState(ctx, cfg.Deployment.App.Name, func(state *AppState) bool {
+		for _, rid = range state.ReplicaSetIds {
+			if rid.Name == replicaSet && rid.Config.Deployment.Id == cfg.Deployment.Id {
+				if !rid.HasRouted && routed {
+					rid.HasRouted = true
+					return true // modified
+				}
+				return false // unmodified
 			}
 		}
+		rid = &ReplicaSetId{
+			Config:    cfg,
+			Name:      replicaSet,
+			HasRouted: routed,
+		}
 		state.ReplicaSetIds = append(state.ReplicaSetIds, rid)
-		return true
+		return true // modified
 	})
-	if err != nil {
-		return fmt.Errorf("register replica set %v: %v", rid, err)
-	}
-	return nil
+	return rid, err
 }
 
 // RegisterActiveComponent registers the given component has been activated. It
@@ -229,8 +235,8 @@ func (a *Assigner) RegisterActiveComponent(ctx context.Context, req *nanny.Activ
 	if err := a.registerApp(ctx, appName); err != nil {
 		return err
 	}
-	rid := &ReplicaSetId{Config: req.Config, Name: rsName}
-	if err := a.registerReplicaSet(ctx, rid); err != nil {
+	rid, err := a.registerReplicaSet(ctx, req.Config, rsName, req.Routed)
+	if err != nil {
 		return err
 	}
 
@@ -239,7 +245,9 @@ func (a *Assigner) RegisterActiveComponent(ctx context.Context, req *nanny.Activ
 	}
 
 	// Create an initial assignment for the component.
+	var cur *ReplicaSetInfo
 	if _, _, err := a.applyReplicaSetInfo(ctx, rid, func(rs *ReplicaSetInfo) bool {
+		cur = rs
 		if rs.Components == nil {
 			rs.Components = map[string]*Assignment{}
 		}
@@ -255,6 +263,13 @@ func (a *Assigner) RegisterActiveComponent(ctx context.Context, req *nanny.Activ
 	}); err != nil {
 		return err
 	}
+
+	// If this is a first routed component in a given ReplicaSet, we need
+	// to start checkers for replicas/Pods that have already been registered.
+	if err := a.updateCheckers(rid, cur, protos.HealthStatus_HEALTHY); err != nil {
+		return err
+	}
+
 	return a.mayGenerateNewRoutingInfo(ctx, rid)
 }
 
@@ -290,8 +305,8 @@ func (a *Assigner) RegisterReplica(ctx context.Context, req *nanny.RegisterRepli
 	if err := a.registerApp(ctx, appName); err != nil {
 		return err
 	}
-	rid := &ReplicaSetId{Config: req.Config, Name: req.ReplicaSet}
-	if err := a.registerReplicaSet(ctx, rid); err != nil {
+	rid, err := a.registerReplicaSet(ctx, req.Config, req.ReplicaSet, false /*routed*/)
+	if err != nil {
 		return err
 	}
 
@@ -314,6 +329,10 @@ func (a *Assigner) RegisterReplica(ctx context.Context, req *nanny.RegisterRepli
 		return err
 	}
 
+	if !rid.HasRouted {
+		return nil
+	}
+
 	a.addChecker(rid, req.WeaveletAddress, req.PodName, req.BabysitterAddress, protos.HealthStatus_HEALTHY)
 	return a.mayGenerateNewRoutingInfo(ctx, rid)
 }
@@ -347,8 +366,8 @@ func (a *Assigner) RegisterListener(ctx context.Context, req *nanny.ExportListen
 	if err := a.registerApp(ctx, req.Config.Deployment.App.Name); err != nil {
 		return err
 	}
-	rid := &ReplicaSetId{Config: req.Config, Name: req.ReplicaSet}
-	if err := a.registerReplicaSet(ctx, rid); err != nil {
+	rid, err := a.registerReplicaSet(ctx, req.Config, req.ReplicaSet, false /*routed*/)
+	if err != nil {
 		return err
 	}
 
@@ -868,6 +887,9 @@ func (a *Assigner) advanceAssignments(ctx context.Context) error {
 		}
 
 		for _, rid := range appState.ReplicaSetIds {
+			if !rid.HasRouted {
+				continue
+			}
 			if err := a.mayGenerateNewRoutingInfo(ctx, rid); err != nil {
 				errs = append(errs, err)
 			}
@@ -920,6 +942,9 @@ func (a *Assigner) annealCheckersForApp(ctx context.Context, app string) error {
 	// Add any new checkers.
 	var errs []error
 	for _, rid := range state.ReplicaSetIds {
+		if !rid.HasRouted {
+			continue
+		}
 		replicaSet, version, err := a.loadReplicaSetInfo(ctx, rid)
 		if err != nil {
 			errs = append(errs, err)