From 48d747b6bb44ac6c932751bcaaf7b27283ab5350 Mon Sep 17 00:00:00 2001
From: Aditya Thebe <contact@adityathebe.com>
Date: Fri, 22 Nov 2024 08:39:04 +0545
Subject: [PATCH] feat: only set namespace for namespaced resources

---
 api/v1/checks.go              | 17 ++++++++++---
 checks/kubernetes_resource.go | 48 ++++++++++++++++++++++++++++++++---
 2 files changed, 59 insertions(+), 6 deletions(-)

diff --git a/api/v1/checks.go b/api/v1/checks.go
index 56ec70994..34e415cef 100644
--- a/api/v1/checks.go
+++ b/api/v1/checks.go
@@ -16,6 +16,7 @@ import (
 	"github.com/samber/lo"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	k8sTypes "k8s.io/apimachinery/pkg/types"
 )
 
@@ -978,17 +979,27 @@ type KubernetesResourceCheck struct {
 	WaitFor KubernetesResourceCheckWaitFor `json:"waitFor,omitempty"`
 }
 
+func (c *KubernetesResourceCheck) HasResourcesWithMissingNamespace() bool {
+	for _, r := range append(c.StaticResources, c.Resources...) {
+		if r.GetNamespace() == "" {
+			return true
+		}
+	}
+
+	return false
+}
+
 // SetMissingNamespace will set the parent canaries name to resources whose namespace
 // is not explicitly specified.
-func (c *KubernetesResourceCheck) SetMissingNamespace(parent Canary) {
+func (c *KubernetesResourceCheck) SetMissingNamespace(parent Canary, namespacedResources map[schema.GroupVersionKind]bool) {
 	for i, r := range c.StaticResources {
-		if r.GetNamespace() == "" {
+		if r.GetNamespace() == "" && namespacedResources[r.GroupVersionKind()] {
 			c.StaticResources[i].SetNamespace(parent.GetNamespace())
 		}
 	}
 
 	for i, r := range c.Resources {
-		if r.GetNamespace() == "" {
+		if r.GetNamespace() == "" && namespacedResources[r.GroupVersionKind()] {
 			c.Resources[i].SetNamespace(parent.GetNamespace())
 		}
 	}
diff --git a/checks/kubernetes_resource.go b/checks/kubernetes_resource.go
index 83159836b..39e2d9acc 100644
--- a/checks/kubernetes_resource.go
+++ b/checks/kubernetes_resource.go
@@ -12,6 +12,7 @@ import (
 	"github.com/flanksource/gomplate/v3"
 	"github.com/flanksource/is-healthy/pkg/health"
 	"github.com/flanksource/is-healthy/pkg/lua"
+	"github.com/patrickmn/go-cache"
 	"github.com/samber/lo"
 	"github.com/sethvargo/go-retry"
 	"golang.org/x/sync/errgroup"
@@ -70,9 +71,6 @@ func (c *KubernetesResourceChecker) Check(ctx context.Context, check v1.Kubernet
 		return results.Failf("validation: %v", err)
 	}
 
-	check.SetMissingNamespace(ctx.Canary)
-	check.SetCanaryOwnerReference(ctx.Canary)
-
 	if check.Kubeconfig != nil {
 		var err error
 		ctx, err = ctx.WithKubeconfig(*check.Kubeconfig)
@@ -81,6 +79,17 @@ func (c *KubernetesResourceChecker) Check(ctx context.Context, check v1.Kubernet
 		}
 	}
 
+	if check.HasResourcesWithMissingNamespace() {
+		namespacedResources, err := fetchNamespacedResources(ctx)
+		if err != nil {
+			return results.Failf("failed to get api resources: %w", err)
+		}
+
+		check.SetMissingNamespace(ctx.Canary, namespacedResources)
+	}
+
+	check.SetCanaryOwnerReference(ctx.Canary)
+
 	if err := templateKubernetesResourceCheck(ctx.Canary.GetPersistedID(), ctx.Canary.GetCheckID(check.GetName()), &check); err != nil {
 		return results.Failf("templating error: %v", err)
 	}
@@ -478,3 +487,36 @@ func templateKubernetesResourceCheck(canaryID, checkID string, check *v1.Kuberne
 
 	return nil
 }
+
+var apiResourceCache = cache.New(time.Hour*24, time.Hour*24)
+
+func fetchNamespacedResources(ctx context.Context) (map[schema.GroupVersionKind]bool, error) {
+	kubeconfigCacheKey := ctx.KubernetesRestConfig().Host + ctx.KubernetesRestConfig().APIPath
+	if val, ok := apiResourceCache.Get(kubeconfigCacheKey); ok {
+		return val.(map[schema.GroupVersionKind]bool), nil
+	}
+
+	_, resourceList, err := ctx.Kubernetes().Discovery().ServerGroupsAndResources()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get server groups & resources: %w", err)
+	}
+
+	namespaceResources := make(map[schema.GroupVersionKind]bool)
+	for _, apiResourceList := range resourceList {
+		for _, resource := range apiResourceList.APIResources {
+			if resource.Namespaced {
+				gv, _ := schema.ParseGroupVersion(apiResourceList.GroupVersion)
+				key := schema.GroupVersionKind{
+					Group:   gv.Group,
+					Version: gv.Version,
+					Kind:    resource.Kind,
+				}
+
+				namespaceResources[key] = true
+			}
+		}
+	}
+
+	apiResourceCache.SetDefault(kubeconfigCacheKey, namespaceResources)
+	return namespaceResources, nil
+}