policy: Remove useless parsing of old CNP/CCNP

Whenever we handle an update event for a CNP or a CCNP, we should not
parse again the old version of the policy, since what comes from the CNP
cache has already been parsed and sanitized when handling the previous
upsert event.

Signed-off-by: Fabio Falzoi <[email protected]>

pkg/k8s/watchers/cilium_network_policy.go

@@ -5,7 +5,6 @@ package watchers
 
 import (
 	"context"
-	"errors"
 	"sync/atomic"
 
 	"github.com/sirupsen/logrus"
@@ -362,25 +361,7 @@ func (k *K8sWatcher) deleteCiliumNetworkPolicyV2(cnp *types.SlimCNP, resourceID
 func (k *K8sWatcher) updateCiliumNetworkPolicyV2(ciliumNPClient clientset.Interface,
 	oldRuleCpy, newRuleCpy *types.SlimCNP, initialRecvTime time.Time, resourceID ipcacheTypes.ResourceID) error {
 
-	_, err := oldRuleCpy.Parse()
-	if err != nil {
-		ns := oldRuleCpy.GetNamespace() // Disambiguates CNP & CCNP
-
-		// We want to ignore parsing errors for empty policies, otherwise the
-		// update to the new policy will be skipped.
-		switch {
-		case ns != "" && !errors.Is(err, cilium_v2.ErrEmptyCNP):
-			log.WithError(err).WithField(logfields.Object, logfields.Repr(oldRuleCpy)).
-				Warn("Error parsing old CiliumNetworkPolicy rule")
-			return err
-		case ns == "" && !errors.Is(err, cilium_v2.ErrEmptyCCNP):
-			log.WithError(err).WithField(logfields.Object, logfields.Repr(oldRuleCpy)).
-				Warn("Error parsing old CiliumClusterwideNetworkPolicy rule")
-			return err
-		}
-	}
-
-	_, err = newRuleCpy.Parse()
+	_, err := newRuleCpy.Parse()
 	if err != nil {
 		log.WithError(err).WithField(logfields.Object, logfields.Repr(newRuleCpy)).
 			Warn("Error parsing new CiliumNetworkPolicy rule")