network: refactor newpodNIC

The factory function newPodNIC exists only to accomodate our tests.
However, it also did something unrelated: verify that a network is
implementable by KubeVirt.

Extracting the verififcation part would allow us to simplify newPodNIC
in a followup commit.

Signed-off-by: Dan Kenigsberg <[email protected]>

pkg/virt-launcher/virtwrap/network/network.go

@@ -71,6 +71,13 @@ func getNetworksAndCniNetworks(vmi *v1.VirtualMachineInstance) (map[string]*v1.N
 	return networks, cniNetworks
 }
 
+func networkIsImplementable(network *v1.Network) error {
+	if network.Pod == nil && network.Multus == nil {
+		return fmt.Errorf("Network not implemented")
+	}
+	return nil
+}
+
 func getPodInterfaceName(networks map[string]*v1.Network, cniNetworks map[string]int, ifaceName string) string {
 	if networks[ifaceName].Multus != nil && !networks[ifaceName].Multus.Default {
 		// multus pod interfaces named netX
@@ -87,6 +94,10 @@ func SetupPodNetworkPhase1(vmi *v1.VirtualMachineInstance, pid int, cacheFactory
 		if !ok {
 			return fmt.Errorf("failed to find a network %s", iface.Name)
 		}
+		err := networkIsImplementable(network)
+		if err != nil {
+			return err
+		}
 		podnic, err := podNICFactory(network, cacheFactory)
 		if err != nil {
 			return err
@@ -107,6 +118,10 @@ func SetupPodNetworkPhase2(vmi *v1.VirtualMachineInstance, domain *api.Domain, c
 		if !ok {
 			return fmt.Errorf("failed to find a network %s", iface.Name)
 		}
+		err := networkIsImplementable(network)
+		if err != nil {
+			return err
+		}
 		podnic, err := podNICFactory(network, cacheFactory)
 		if err != nil {
 			return err
@@ -121,8 +136,5 @@ func SetupPodNetworkPhase2(vmi *v1.VirtualMachineInstance, domain *api.Domain, c
 }
 
 func newpodNIC(network *v1.Network, cacheFactory cache.InterfaceCacheFactory) (podNIC, error) {
-	if network.Pod != nil || network.Multus != nil {
-		return &podNICImpl{cacheFactory: cacheFactory}, nil
-	}
-	return nil, fmt.Errorf("Network not implemented")
+	return &podNICImpl{cacheFactory: cacheFactory}, nil
 }