Parameterize # of GameServer Creation/Deletion

pkg/operator/controllers/config.go

@@ -0,0 +1,20 @@
+package controllers
+
+// Config is a struct containing configuration from environment variables
+// source: https://github.com/caarlos0/env
+type Config struct {
+	ApiServiceSecurity                     string `env:"API_SERVICE_SECURITY"`
+	TlsSecretName                          string `env:"TLS_SECRET_NAME" envDefault:"tls-secret"`
+	TlsSecretNamespace                     string `env:"TLS_SECRET_NAMESPACE" envDefault:"thundernetes-system"`
+	TlsCertificateName                     string `env:"TLS_CERTIFICATE_FILENAME" envDefault:"tls.crt"`
+	TlsPrivateKeyFilename                  string `env:"TLS_PRIVATE_KEY_FILENAME" envDefault:"tls.key"`
+	PortRegistryExclusivelyGameServerNodes bool   `env:"PORT_REGISTRY_EXCLUSIVELY_GAME_SERVER_NODES" envDefault:"false"`
+	LogLevel                               string `env:"LOG_LEVEL" envDefault:"info"`
+	MinPort                                int32  `env:"MIN_PORT" envDefault:"10000"`
+	MaxPort                                int32  `env:"MAX_PORT" envDefault:"12000"`
+	AllocationApiSvcPort                   int32  `env:"ALLOC_API_SVC_PORT" envDefault:"5000"`
+	InitContainerImageLinux                string `env:"THUNDERNETES_INIT_CONTAINER_IMAGE,notEmpty"`
+	InitContainerImageWin                  string `env:"THUNDERNETES_INIT_CONTAINER_IMAGE_WIN,notEmpty"`
+	MaxNumberOfGameServersToAdd            int    `env:"MAX_NUM_GS_TO_ADD" envDefault:"20"`
+	MaxNumberOfGameServersToDelete         int    `env:"MAX_NUM_GS_TO_DEL" envDefault:"20"`
+}

pkg/operator/controllers/gameserverbuild_controller.go

@@ -43,14 +43,6 @@ import (
 // value is the number of crashes
 var crashesPerBuild = sync.Map{}
 
-const (
-	// maximum number of GameServers to create per reconcile loop
-	// we have this in place since each create call is synchronous and we want to minimize the time for each reconcile loop
-	maxNumberOfGameServersToAdd = 20
-	// maximum number of GameServers to delete per reconcile loop
-	maxNumberOfGameServersToDelete = 20
-)
-
 // Simple async map implementation using a mutex
 // used to manage the expected GameServer creations and deletions
 type MutexMap struct {
@@ -65,17 +57,19 @@ type GameServerBuildReconciler struct {
 	PortRegistry *PortRegistry
 	Recorder     record.EventRecorder
 	expectations *GameServerExpectations
+	Config       *Config
 }
 
 // NewGameServerBuildReconciler returns a pointer to a new GameServerBuildReconciler
-func NewGameServerBuildReconciler(mgr manager.Manager, portRegistry *PortRegistry) *GameServerBuildReconciler {
+func NewGameServerBuildReconciler(mgr manager.Manager, portRegistry *PortRegistry, cfg *Config) *GameServerBuildReconciler {
 	cl := mgr.GetClient()
 	return &GameServerBuildReconciler{
 		Client:       cl,
 		Scheme:       mgr.GetScheme(),
 		PortRegistry: portRegistry,
 		Recorder:     mgr.GetEventRecorderFor("GameServerBuild"),
 		expectations: NewGameServerExpectations(cl),
+		Config:       cfg,
 	}
 }
 
@@ -187,12 +181,12 @@ func (r *GameServerBuildReconciler) Reconcile(ctx context.Context, req ctrl.Requ
 	var totalNumberOfGameServersToDelete int = 0
 	// user has decreased standingBy numbers
 	if nonActiveGameServersCount > gsb.Spec.StandingBy {
-		totalNumberOfGameServersToDelete += int(math.Min(float64(nonActiveGameServersCount-gsb.Spec.StandingBy), maxNumberOfGameServersToDelete))
+		totalNumberOfGameServersToDelete += int(math.Min(float64(nonActiveGameServersCount-gsb.Spec.StandingBy), float64(r.Config.MaxNumberOfGameServersToDelete)))
 	}
 	// we also need to check if we are above the max
 	// this can happen if the user modifies the spec.Max during the GameServerBuild's lifetime
 	if nonActiveGameServersCount+activeCount > gsb.Spec.Max {
-		totalNumberOfGameServersToDelete += int(math.Min(float64(totalNumberOfGameServersToDelete+(nonActiveGameServersCount+activeCount-gsb.Spec.Max)), maxNumberOfGameServersToDelete))
+		totalNumberOfGameServersToDelete += int(math.Min(float64(totalNumberOfGameServersToDelete+(nonActiveGameServersCount+activeCount-gsb.Spec.Max)), float64(r.Config.MaxNumberOfGameServersToDelete)))
 	}
 	if totalNumberOfGameServersToDelete > 0 {
 		err := r.deleteNonActiveGameServers(ctx, &gsb, &gameServers, totalNumberOfGameServersToDelete)
@@ -205,12 +199,12 @@ func (r *GameServerBuildReconciler) Reconcile(ctx context.Context, req ctrl.Requ
 	// we're also limiting the number of game servers that are created to avoid issues like this https://github.com/kubernetes-sigs/controller-runtime/issues/1782
 	// we attempt to create the missing number of game servers, but we don't want to create more than the max
 	// an error channel for the go routines to write errors
-	errCh := make(chan error, maxNumberOfGameServersToAdd)
+	errCh := make(chan error, r.Config.MaxNumberOfGameServersToAdd)
 	// a waitgroup for async create calls
 	var wg sync.WaitGroup
 	for i := 0; i < gsb.Spec.StandingBy-nonActiveGameServersCount &&
 		i+nonActiveGameServersCount+activeCount < gsb.Spec.Max &&
-		i < maxNumberOfGameServersToAdd; i++ {
+		i < r.Config.MaxNumberOfGameServersToAdd; i++ {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()

pkg/operator/controllers/suite_test.go

@@ -37,9 +37,11 @@ import (
 )
 
 const (
-	assertPollingInterval = 20 * time.Millisecond
-	assertTimeout         = 2 * time.Second
-	allocationApiSvcPort  = 5000
+	assertPollingInterval          = 20 * time.Millisecond
+	assertTimeout                  = 2 * time.Second
+	allocationApiSvcPort           = 5000
+	maxNumberOfGameServersToAdd    = 20
+	maxNumberOfGameServersToDelete = 20
 )
 
 // These tests use Ginkgo (BDD-style Go testing framework). Refer to
@@ -72,6 +74,8 @@ var _ = BeforeSuite(func() {
 		ErrorIfCRDPathMissing: true,
 	}
 
+	config := &Config{}
+
 	cfg, err := testEnv.Start()
 	Expect(err).NotTo(HaveOccurred())
 	Expect(cfg).NotTo(BeNil())
@@ -98,7 +102,7 @@ var _ = BeforeSuite(func() {
 	err = portRegistry.SetupWithManager(k8sManager)
 	Expect(err).ToNot(HaveOccurred())
 
-	err = (NewGameServerBuildReconciler(k8sManager, portRegistry)).SetupWithManager(k8sManager)
+	err = (NewGameServerBuildReconciler(k8sManager, portRegistry, config)).SetupWithManager(k8sManager)
 	Expect(err).ToNot(HaveOccurred())
 
 	initContainerImageLinux, initContainerImageWin := "testImageLinux", "testImageWin"

pkg/operator/main.go

@@ -48,23 +48,6 @@ import (
 	corev1 "k8s.io/api/core/v1"
 )
 
-// Config is a struct containing configuration from environment variables
-// source: https://github.com/caarlos0/env
-type Config struct {
-	ApiServiceSecurity                     string `env:"API_SERVICE_SECURITY"`
-	TlsSecretName                          string `env:"TLS_SECRET_NAME" envDefault:"tls-secret"`
-	TlsSecretNamespace                     string `env:"TLS_SECRET_NAMESPACE" envDefault:"thundernetes-system"`
-	TlsCertificateName                     string `env:"TLS_CERTIFICATE_FILENAME" envDefault:"tls.crt"`
-	TlsPrivateKeyFilename                  string `env:"TLS_PRIVATE_KEY_FILENAME" envDefault:"tls.key"`
-	PortRegistryExclusivelyGameServerNodes bool   `env:"PORT_REGISTRY_EXCLUSIVELY_GAME_SERVER_NODES" envDefault:"false"`
-	LogLevel                               string `env:"LOG_LEVEL" envDefault:"info"`
-	MinPort                                int32  `env:"MIN_PORT" envDefault:"10000"`
-	MaxPort                                int32  `env:"MAX_PORT" envDefault:"12000"`
-	AllocationApiSvcPort                   int32  `env:"ALLOC_API_SVC_PORT" envDefault:"5000"`
-	InitContainerImageLinux                string `env:"THUNDERNETES_INIT_CONTAINER_IMAGE,notEmpty"`
-	InitContainerImageWin                  string `env:"THUNDERNETES_INIT_CONTAINER_IMAGE_WIN,notEmpty"`
-}
-
 var (
 	scheme   = runtime.NewScheme()
 	setupLog = ctrl.Log.WithName("setup")
@@ -79,7 +62,7 @@ func init() {
 
 func main() {
 	// load configuration from env variables
-	cfg := &Config{}
+	cfg := &controllers.Config{}
 	if err := env.Parse(cfg); err != nil {
 		log.Fatal(err, "Cannot load configuration from environment variables")
 	}
@@ -151,7 +134,7 @@ func main() {
 	}
 
 	// initialize the GameServerBuild controller
-	if err = controllers.NewGameServerBuildReconciler(mgr, portRegistry).SetupWithManager(mgr); err != nil {
+	if err = controllers.NewGameServerBuildReconciler(mgr, portRegistry, cfg).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "GameServerBuild")
 		os.Exit(1)
 	}
@@ -187,7 +170,7 @@ func main() {
 // initializePortRegistry performs some initialization and creates a new PortRegistry struct
 // the k8sClient is a live API client and is used to get the existing gameservers and the "Ready" Nodes
 // the crClient is the cached controller-runtime client, used to watch for changes to the nodes from inside the PortRegistry
-func initializePortRegistry(k8sClient client.Reader, crClient client.Client, setupLog logr.Logger, cfg *Config) (*controllers.PortRegistry, error) {
+func initializePortRegistry(k8sClient client.Reader, crClient client.Client, setupLog logr.Logger, cfg *controllers.Config) (*controllers.PortRegistry, error) {
 	var gameServers mpsv1alpha1.GameServerList
 	if err := k8sClient.List(context.Background(), &gameServers); err != nil {
 		return nil, err
@@ -228,7 +211,7 @@ func initializePortRegistry(k8sClient client.Reader, crClient client.Client, set
 
 // getTlsSecret returns the TLS secret from the given namespace
 // used in the allocation API service
-func getTlsSecret(k8sClient client.Reader, cfg *Config) ([]byte, []byte, error) {
+func getTlsSecret(k8sClient client.Reader, cfg *controllers.Config) ([]byte, []byte, error) {
 	var secret corev1.Secret
 	err := k8sClient.Get(context.Background(), types.NamespacedName{
 		Name:      cfg.TlsSecretName,
@@ -241,7 +224,7 @@ func getTlsSecret(k8sClient client.Reader, cfg *Config) ([]byte, []byte, error)
 }
 
 // validateMinMaxPort validates minimum and maximum ports
-func validateMinMaxPort(cfg *Config) (int32, int32, error) {
+func validateMinMaxPort(cfg *controllers.Config) (int32, int32, error) {
 	if cfg.MinPort >= cfg.MaxPort {
 		return 0, 0, errors.New("MIN_PORT cannot be greater or equal than MAX_PORT")
 	}
@@ -273,7 +256,7 @@ func getLogLevel(logLevel string) zapcore.LevelEnabler {
 // for this to happen, user has to set "API_SERVICE_SECURITY" env as "usetls" and set the env "TLS_SECRET_NAMESPACE" with the namespace
 // that contains the Kubernetes Secret with the cert
 // if any of the mentioned conditions are not set, method returns nil
-func getCrtKeyIfTlsEnabled(c client.Reader, cfg *Config) ([]byte, []byte) {
+func getCrtKeyIfTlsEnabled(c client.Reader, cfg *controllers.Config) ([]byte, []byte) {
 	if cfg.ApiServiceSecurity == "usetls" {
 		crt, key, err := getTlsSecret(c, cfg)
 		if err != nil {