Support running ip reconciler with KUBECONFIG

Sometimes, we want to run the reconciler outside of the cluster for development convenience. This patch allows the reconciler process to use the KUBECONFIG environment variable. Signed-off-by: Peng Liu <[email protected]>
k8snetworkplumbingwg · Mar 4, 2024 · c9e55dd · c9e55dd
1 parent 271aa86
commit c9e55dd
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Showing 2 changed files with 23 additions and 4 deletions.
diff --git a/cmd/controlloop/controlloop.go b/cmd/controlloop/controlloop.go
@@ -15,6 +15,7 @@ import (
 	typedcorev1 "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/record"
+	"k8s.io/client-go/tools/clientcmd"
 
 	nadclient "github.com/k8snetworkplumbingwg/network-attachment-definition-client/pkg/client/clientset/versioned"
 	nadinformers "github.com/k8snetworkplumbingwg/network-attachment-definition-client/pkg/client/informers/externalversions"
@@ -125,9 +126,19 @@ func handleSignals(stopChannel chan struct{}, signals ...os.Signal) {
 }
 
 func newPodController(stopChannel chan struct{}) (*controlloop.PodController, error) {
-	cfg, err := rest.InClusterConfig()
+	var cfg *rest.Config
+	var err error
+	cfg, err = rest.InClusterConfig()
 	if err != nil {
-		return nil, fmt.Errorf("failed to implicitly generate the kubeconfig: %w", err)
+		logging.Debugf("failed to generate the kubeconfig from service account: %v", err)
+		kubeConfigFile := os.Getenv("KUBECONFIG")
+		if kubeConfigFile == "" {
+			return nil, fmt.Errorf("KUBECONFIG environment variable not set")
+		}
+		cfg, err = clientcmd.BuildConfigFromFlags("", kubeConfigFile)
+		if err != nil {
+			return nil, fmt.Errorf("failed to generate kubeconfig from file %s: %v", kubeConfigFile, err)
+		}
 	}
 
 	k8sClientSet, err := kubernetes.NewForConfig(cfg)

diff --git a/pkg/reconciler/ip.go b/pkg/reconciler/ip.go
@@ -2,6 +2,7 @@ package reconciler
 
 import (
 	"context"
+	"os"
 	"time"
 
 	"github.com/k8snetworkplumbingwg/whereabouts/pkg/logging"
@@ -16,13 +17,20 @@ func ReconcileIPs(errorChan chan error) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(defaultReconcilerTimeout*time.Second))
 	defer cancel()
 
-	ipReconcileLoop, err := NewReconcileLooper(ctx, defaultReconcilerTimeout)
+	var err error
+	var ipReconcileLoop *ReconcileLooper
+	kubeConfigFile := os.Getenv("KUBECONFIG")
+
+	if kubeConfigFile == "" {
+		ipReconcileLoop, err = NewReconcileLooper(ctx, defaultReconcilerTimeout)
+	} else {
+		ipReconcileLoop, err = NewReconcileLooperWithKubeconfig(ctx, kubeConfigFile, defaultReconcilerTimeout)
+	}
 	if err != nil {
 		_ = logging.Errorf("failed to create the reconcile looper: %v", err)
 		errorChan <- err
 		return
 	}
-
 	cleanedUpIps, err := ipReconcileLoop.ReconcileIPPools(ctx)
 	if err != nil {
 		_ = logging.Errorf("failed to clean up IP for allocations: %v", err)