Added deprecation warning for --network-plugin=cni

Signed-off-by: Pablo Caderno <[email protected]>

Author: kadern0

cmd/minikube/cmd/start_flags.go

@@ -276,6 +276,15 @@ func generateClusterConfig(cmd *cobra.Command, existing *config.ClusterConfig, k
 			glog.Errorf("Found deprecated --enable-default-cni flag, setting --cni=bridge")
 			chosenCNI = "bridge"
 		}
+		// networkPlugin cni deprecation warning
+		chosenNetworkPlugin := viper.GetString(networkPlugin)
+		if chosenNetworkPlugin == "cni" {
+			glog.Errorf("Found deprecated --network-plugin=cni flag (new flag: --cni), setting --cni=auto if not already set")
+			if chosenCNI == "" {
+				chosenCNI = "auto"
+			}
+			chosenNetworkPlugin = ""
+		}
 
 		cc = config.ClusterConfig{
 			Name:                    ClusterFlagValue(),
@@ -321,7 +330,7 @@ func generateClusterConfig(cmd *cobra.Command, existing *config.ClusterConfig, k
 				FeatureGates:           viper.GetString(featureGates),
 				ContainerRuntime:       viper.GetString(containerRuntime),
 				CRISocket:              viper.GetString(criSocket),
-				NetworkPlugin:          viper.GetString(networkPlugin),
+				NetworkPlugin:          chosenNetworkPlugin,
 				ServiceCIDR:            viper.GetString(serviceCIDR),
 				ImageRepository:        repository,
 				ExtraOptions:           config.ExtraOptions,