Create a manager cache only when a ns is specified:

A cache with a "" namespace causes reconcile errors:
"unable to get: namespace/machine because of unknown namespace for the cache"
With this change is the ns is "" we use the default behavior
of the manager which is to watch and list all namespaces.

Signed-off-by: Jacob Weinstock <[email protected]>

main.go

@@ -116,18 +116,23 @@ func main() {
 
 	setupLog.Info("Watching objects in namespace for reconciliation", "namespace", kubeNamespace)
 
-	mgr, err := ctrl.NewManager(cfg, ctrl.Options{
+	opts := ctrl.Options{
 		Scheme: scheme,
-		Cache: cache.Options{
-			DefaultNamespaces: map[string]cache.Config{kubeNamespace: {}},
-		},
 		Metrics: metricsserver.Options{
 			BindAddress: metricsAddr,
 		},
 		HealthProbeBindAddress: probeAddr,
 		LeaderElection:         enableLeaderElection,
 		LeaderElectionID:       "e74dec1a.tinkerbell.org",
-	})
+	}
+	// If a namespace is specified, only watch that namespace. Otherwise, watch all namespaces.
+	if kubeNamespace != "" {
+		opts.Cache = cache.Options{
+			DefaultNamespaces: map[string]cache.Config{kubeNamespace: {}},
+		}
+	}
+
+	mgr, err := ctrl.NewManager(cfg, opts)
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")
 		os.Exit(1)