From 77fa40713d9e601f10df875328dbca15b85d704a Mon Sep 17 00:00:00 2001
From: Maanas M Singh <59373661+Maanas-23@users.noreply.github.com>
Date: Thu, 2 Jan 2025 19:49:54 +0530
Subject: [PATCH] Call reconcile from server (#58)

* calling reconcile from server

* reconcile if crd is not found in CRDDirectory

* remove ForceReconcile function

* fix goimports lint and update error messages

* undo accidental change

* fix goimports lint

---------

Co-authored-by: Shubham Rai <shubham.rai.iitg@gmail.com>
---
 operator/cmd/main.go                          |  7 +++--
 .../internal/elastiserver/elastiServer.go     | 29 ++++++++++++++++---
 2 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/operator/cmd/main.go b/operator/cmd/main.go
index 3207f45..f655f1a 100644
--- a/operator/cmd/main.go
+++ b/operator/cmd/main.go
@@ -175,19 +175,20 @@ func mainWithError() error {
 	informerManager.Start()
 
 	// Set up the ElastiService controller
-	if err = (&controller.ElastiServiceReconciler{
+	reconciler := &controller.ElastiServiceReconciler{
 		Client:          mgr.GetClient(),
 		Scheme:          mgr.GetScheme(),
 		Logger:          zapLogger,
 		InformerManager: informerManager,
-	}).SetupWithManager(mgr); err != nil {
+	}
+	if err = reconciler.SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "ElastiService")
 		sentry.CaptureException(err)
 		return fmt.Errorf("main: %w", err)
 	}
 
 	// Start the elasti server
-	eServer := elastiserver.NewServer(zapLogger, mgr.GetConfig(), 30*time.Second)
+	eServer := elastiserver.NewServer(zapLogger, mgr.GetConfig(), 30*time.Second, reconciler)
 	errChan := make(chan error, 1)
 	go func() {
 		if err := eServer.Start(elastiServerPort); err != nil {
diff --git a/operator/internal/elastiserver/elastiServer.go b/operator/internal/elastiserver/elastiServer.go
index 55330b5..ceab36a 100644
--- a/operator/internal/elastiserver/elastiServer.go
+++ b/operator/internal/elastiserver/elastiServer.go
@@ -14,11 +14,14 @@ import (
 
 	sentryhttp "github.com/getsentry/sentry-go/http"
 
+	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/rest"
 
 	"truefoundry/elasti/operator/internal/crddirectory"
 	"truefoundry/elasti/operator/internal/prom"
 
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/truefoundry/elasti/pkg/k8shelper"
 	"github.com/truefoundry/elasti/pkg/messages"
@@ -39,10 +42,11 @@ type (
 		scaleLocks sync.Map
 		// rescaleDuration is the duration to wait before checking to rescaling the target
 		rescaleDuration time.Duration
+		reconciler      reconcile.Reconciler
 	}
 )
 
-func NewServer(logger *zap.Logger, config *rest.Config, rescaleDuration time.Duration) *Server {
+func NewServer(logger *zap.Logger, config *rest.Config, rescaleDuration time.Duration, reconciler reconcile.Reconciler) *Server {
 	// Get Ops client
 	k8sUtil := k8shelper.NewOps(logger, config)
 	return &Server{
@@ -50,6 +54,7 @@ func NewServer(logger *zap.Logger, config *rest.Config, rescaleDuration time.Dur
 		k8shelper: k8sUtil,
 		// rescaleDuration is the duration to wait before checking to rescaling the target
 		rescaleDuration: rescaleDuration,
+		reconciler:      reconciler,
 	}
 }
 
@@ -148,7 +153,7 @@ func (s *Server) resolverReqHandler(w http.ResponseWriter, req *http.Request) {
 		zap.String("namespace", body.Namespace))
 }
 
-func (s *Server) scaleTargetForService(_ context.Context, serviceName, namespace string) error {
+func (s *Server) scaleTargetForService(ctx context.Context, serviceName, namespace string) error {
 	scaleMutex, loaded := s.getMutexForServiceScale(serviceName)
 	if loaded {
 		s.logger.Debug("Scale target lock already exists", zap.String("service", serviceName))
@@ -157,10 +162,26 @@ func (s *Server) scaleTargetForService(_ context.Context, serviceName, namespace
 	scaleMutex.Lock()
 	defer s.logger.Debug("Scale target lock released", zap.String("service", serviceName))
 	s.logger.Debug("Scale target lock taken", zap.String("service", serviceName))
+
 	crd, found := crddirectory.CRDDirectory.GetCRD(serviceName)
 	if !found {
-		s.releaseMutexForServiceScale(serviceName)
-		return fmt.Errorf("scaleTargetForService - error: failed to get CRD details from directory, serviceName: %s", serviceName)
+		s.logger.Debug("Failed to get CRD details from directory, running reconcile")
+		_, err := s.reconciler.Reconcile(ctx, reconcile.Request{
+			NamespacedName: types.NamespacedName{
+				Name:      serviceName,
+				Namespace: namespace,
+			},
+		})
+		if err != nil {
+			s.releaseMutexForServiceScale(serviceName)
+			return fmt.Errorf("scaleTargetForService - error: reconcile failed, serviceName: %s, %w", serviceName, err)
+		}
+
+		crd, found = crddirectory.CRDDirectory.GetCRD(serviceName)
+		if !found {
+			s.releaseMutexForServiceScale(serviceName)
+			return fmt.Errorf("scaleTargetForService - error: failed to get CRD details from directory even after reconcile, serviceName: %s", serviceName)
+		}
 	}
 
 	if err := s.k8shelper.ScaleTargetWhenAtZero(namespace, crd.Spec.ScaleTargetRef.Name, crd.Spec.ScaleTargetRef.Kind, crd.Spec.MinTargetReplicas); err != nil {