From a287bed75538c313d4ede915114b43fdba8db6bb Mon Sep 17 00:00:00 2001
From: aasifkhan7 <aasifk106@gmail.com>
Date: Sun, 29 Dec 2024 18:41:09 +0530
Subject: [PATCH] remove unused network policy as well

---
 pkg/determiner/determiner.go | 25 ++++++++++++++++++++++++-
 pkg/resource/resource.go     | 16 ++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/pkg/determiner/determiner.go b/pkg/determiner/determiner.go
index 1496546..f086523 100644
--- a/pkg/determiner/determiner.go
+++ b/pkg/determiner/determiner.go
@@ -138,12 +138,35 @@ func (d *determiner) DetermineDeletion(ctx context.Context, info *cliresource.In
 
 	case resource.KindHorizontalPodAutoscaler:
 		return d.determineDeletionHorizontalPodAutoscaler(ctx, info)
-
+	case resource.KindNetworkPolicy:
+        return d.determineDeletionNetworkPolicy(info)
 	default:
 		return false, fmt.Errorf("unsupported kind: %s/%s", kind, info.Name)
 	}
 }
 
+func (d *determiner) determineDeletionNetworkPolicy(info *cliresource.Info) (bool, error) {
+    np, err := resource.ObjectToNetworkPolicy(info.Object)
+    if err != nil {
+        return false, err
+    }
+
+    // Get the selector from the Network Policy
+    selector, err := metav1.LabelSelectorAsSelector(&np.Spec.PodSelector)
+    if err != nil {
+        return false, fmt.Errorf("invalid label selector (%s): %w", np.Name, err)
+    }
+
+    // Iterate over pods to check if any match the selector
+    for _, pod := range d.pods {
+        if selector.Matches(labels.Set(pod.Labels)) {
+            return false, nil // Pod matches the selector, so the Network Policy is used
+        }
+    }
+
+    return true, nil // No pods match the selector, so the Network Policy is unused
+}
+
 func (d *determiner) determineDeletionPod(info *cliresource.Info) (bool, error) {
 	pod, err := resource.ObjectToPod(info.Object)
 	if err != nil {
diff --git a/pkg/resource/resource.go b/pkg/resource/resource.go
index df0fd81..46b2ff1 100644
--- a/pkg/resource/resource.go
+++ b/pkg/resource/resource.go
@@ -7,6 +7,7 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	policyv1beta1 "k8s.io/api/policy/v1beta1"
 	"k8s.io/apimachinery/pkg/runtime"
+	networkingv1 "k8s.io/api/networking/v1"
 )
 
 const (
@@ -20,6 +21,7 @@ const (
 	KindJob                     = "Job"
 	KindPodDisruptionBudget     = "PodDisruptionBudget"
 	KindHorizontalPodAutoscaler = "HorizontalPodAutoscaler"
+	KindNetworkPolicy           = "NetworkPolicy"
 )
 
 var unstructuredConverter = runtime.DefaultUnstructuredConverter
@@ -108,6 +110,20 @@ func ObjectToHorizontalPodAutoscaler(obj runtime.Object) (*autoscalingv1.Horizon
 	return &hpa, nil
 }
 
+func ObjectToNetworkPolicy(obj runtime.Object) (*networkingv1.NetworkPolicy, error) {
+    u, err := toUnstructured(obj)
+    if err != nil {
+        return nil, err
+    }
+
+    var np networkingv1.NetworkPolicy
+    if err := fromUnstructured(u, &np); err != nil {
+        return nil, err
+    }
+
+    return &np, nil
+}
+
 func toUnstructured(obj runtime.Object) (map[string]interface{}, error) {
 	return unstructuredConverter.ToUnstructured(obj)
 }