more changes

internal/controller/resolution_controller.go

@@ -17,11 +17,11 @@ limitations under the License.
 package controller
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"net"
 	"slices"
+	"time"
 
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -30,6 +30,7 @@ import (
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 
 	dnsv1 "stinnesbeck.com/dns/api/v1"
+	v1 "stinnesbeck.com/dns/api/v1"
 )
 
 // ResolutionReconciler reconciles a Resolution object
@@ -68,16 +69,31 @@ func (r *ResolutionReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 		return ctrl.Result{}, err
 	}
 
+	resolver := net.DefaultResolver
+
+	// check if a resolver was given
+	if resolution.Spec.Resolver != nil {
+		customResolver, err := r.getResolver(ctx, req, &resolution)
+		if err != nil {
+			return ctrl.Result{}, err
+		}
+
+		resolution.Status.Resolver = resolution.Spec.Resolver
+		resolver = customResolver
+	}
+
 	// Snapshot before mutation
 	patchBase := resolution.DeepCopy()
 
-	addrs, err := net.LookupHost(resolution.Spec.Address)
+	var addrs []string
+
+	addrs, err := resolver.LookupHost(ctx, resolution.Spec.Address)
 	if err != nil {
 		log.Error(err, "error while resolving resolution")
 		return ctrl.Result{}, err
 	}
 
-	// Build new desired status (IMPORTANT: no append)
+	// Build new desired status
 	var ips []net.IP
 	for _, addr := range addrs {
 		if ip := net.ParseIP(addr); ip != nil {
@@ -85,24 +101,11 @@ func (r *ResolutionReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 		}
 	}
 
-	slices.SortStableFunc(ips, func(a, b net.IP) int {
-		for i := range 15 {
-			if a[i] < b[i] {
-				return -1
-			}
-
-			if a[i] > b[i] {
-				return 1
-			}
-		}
-
-		return 0
-	})
+	// sort to make states comparable
+	slices.SortStableFunc(ips, stableSortIPs)
 
 	// check if both ip address slices are the same
-	if slices.EqualFunc(patchBase.Status.IPAddresses, ips, func(s1, s2 net.IP) bool {
-		return bytes.Equal(s1, s2)
-	}) {
+	if slices.EqualFunc(patchBase.Status.IPAddresses, ips, equalIPs) {
 		return ctrl.Result{}, nil
 	}
 
@@ -111,30 +114,70 @@ func (r *ResolutionReconciler) Reconcile(ctx context.Context, req ctrl.Request)
 	resolution.Status.IPAddresses = ips
 
 	// Only patch status (clean + minimal diff)
-	if err := r.Status().Patch(
-		ctx,
-		&resolution,
-		client.MergeFrom(patchBase),
-	); err != nil {
+	if err := r.Status().Patch(ctx, &resolution, client.MergeFrom(patchBase)); err != nil {
 		return ctrl.Result{}, err
 	}
 
 	return ctrl.Result{}, nil
+}
 
-	// if err := r.Patch(ctx, &resolution, client.Merge); err != nil {
+func (r *ResolutionReconciler) getResolver(ctx context.Context, req ctrl.Request, resolution *v1.Resolution) (*net.Resolver, error) {
+	var resolver v1.Resolver
+
+	resolverFQDN := client.ObjectKey{
+		Namespace: req.Namespace,
+		Name:      *resolution.Spec.Resolver,
+	}
+
+	if err := r.Get(ctx, resolverFQDN, &resolver); err != nil {
+		// retrieval of resolver failed
+		return nil, err
+	}
+
+	netResolver := net.Resolver{
+		PreferGo: true,
+		Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
+			d := net.Dialer{
+				Timeout: 3 * time.Second,
+			}
+			return d.DialContext(ctx, network, fmt.Sprintf("%s:%d", resolver.Spec.IPAddress, resolver.Spec.Port))
+		},
+	}
+
+	return &netResolver, nil
+
+	// // Snapshot before mutation
+	// patchBase := resolution.DeepCopy()
+
+	// ip, _ := netResolver.LookupHost(context.Background(), resolution.Spec.Address)
+
+	// if err := r.Status().Patch(ctx, resolution, client.MergeFrom(patchBase)); err != nil {
 	// 	return ctrl.Result{}, err
 	// }
 
-	// r := &net.Resolver{
-	// 	PreferGo: true,
-	// 	Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
-	// 		d := net.Dialer{
-	// 			Timeout: time.Millisecond * time.Duration(10000),
-	// 		}
-	// 		return d.DialContext(ctx, network, "8.8.8.8:53")
-	// 	},
-	// }
-	// ip, _ := r.LookupHost(context.Background(), "www.google.com")
+	// return ctrl.Result{}, nil
+}
+
+func equalIPs(a, b net.IP) bool {
+	return a.Equal(b)
+}
+
+func stableSortIPs(a, b net.IP) int {
+	if len(a) != len(b) {
+		a, b = a.To16(), b.To16()
+	}
+
+	for i := range a {
+		if a[i] < b[i] {
+			return -1
+		}
+
+		if a[i] > b[i] {
+			return 1
+		}
+	}
+
+	return 0
 }
 
 // SetupWithManager sets up the controller with the Manager.