Fix node-disruption-types containing empty strings

Split was containing empty string. Now we filter them out
to avoid rejecting maintenances.

Author: geobeau

cmd/main.go

@@ -35,6 +35,7 @@ import (
 
 	nodedisruptionv1alpha1 "github.com/criteo/node-disruption-controller/api/v1alpha1"
 	"github.com/criteo/node-disruption-controller/internal/controller"
+	"github.com/criteo/node-disruption-controller/pkg/utils"
 	//+kubebuilder:scaffold:imports
 )
 
@@ -57,7 +58,7 @@ func main() {
 	var rejectEmptyNodeDisruption bool
 	var retryInterval time.Duration
 	var rejectOverlappingDisruption bool
-	var nodeDisruptionTypes string
+	var nodeDisruptionTypesRaw string
 	flag.StringVar(&metricsAddr, "metrics-bind-address", ":8080", "The address the metric endpoint binds to.")
 	flag.StringVar(&probeAddr, "health-probe-bind-address", ":8081", "The address the probe endpoint binds to.")
 	flag.BoolVar(&enableLeaderElection, "leader-elect", false,
@@ -66,7 +67,7 @@ func main() {
 	flag.BoolVar(&rejectEmptyNodeDisruption, "reject-empty-node-disruption", false, "Reject NodeDisruption matching no actual node.")
 	flag.DurationVar(&retryInterval, "retry-interval", controller.DefaultRetryInterval, "How long to wait between each retry (Default 60s)")
 	flag.BoolVar(&rejectOverlappingDisruption, "reject-overlapping-disruption", false, "Automatically reject any overlapping NodeDisruption (based on node selector), preserving the oldest one")
-	flag.StringVar(&nodeDisruptionTypes, "node-disruption-types", "", "The list of types allowed for a node disruption separated by a comma.")
+	flag.StringVar(&nodeDisruptionTypesRaw, "node-disruption-types", "", "The list of types allowed for a node disruption separated by a comma.")
 
 	opts := zap.Options{
 		Development: true,
@@ -100,14 +101,16 @@ func main() {
 		os.Exit(1)
 	}
 
+	nodeDisruptionTypes := utils.FilterEmptyString(strings.Split(nodeDisruptionTypesRaw, ","))
+
 	if err = (&controller.NodeDisruptionReconciler{
 		Client: mgr.GetClient(),
 		Scheme: mgr.GetScheme(),
 		Config: controller.NodeDisruptionReconcilerConfig{
 			RejectEmptyNodeDisruption:   rejectEmptyNodeDisruption,
 			RetryInterval:               retryInterval,
 			RejectOverlappingDisruption: rejectOverlappingDisruption,
-			NodeDisruptionTypes:         strings.Split(nodeDisruptionTypes, ","),
+			NodeDisruptionTypes:         nodeDisruptionTypes,
 		},
 	}).SetupWithManager(mgr); err != nil {
 		setupLog.Error(err, "unable to create controller", "controller", "NodeDisruption")

pkg/utils/utils.go

@@ -0,0 +1,10 @@
+package utils
+
+func FilterEmptyString(source []string) (filtered []string) {
+	for _, element := range source {
+		if element != "" {
+			filtered = append(filtered, element)
+		}
+	}
+	return filtered
+}

pkg/utils/utils_test.go

@@ -0,0 +1,15 @@
+package utils
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestFilterEmptyString(t *testing.T) {
+	result := FilterEmptyString(strings.Split(",,foo,,bar,,", ","))
+	expected := []string{"foo", "bar"}
+	if !reflect.DeepEqual(result, expected) {
+		t.Fatalf("Mismatching strings: %s != %s", result, expected)
+	}
+}