feat: add --kubeconfig flag (#858)

* feat: add --kubeconfig flag

* docs: add kubeconfig flag example

README.md

@@ -194,6 +194,11 @@ kubescape scan framework mitre --submit
 kubescape scan control "Privileged container"
 ```
 
+#### Scan using an anternative kubeconfig file
+```
+kubescape scan --kubeconfig cluster.conf
+```
+
 #### Scan specific namespaces
 ```
 kubescape scan --include-namespaces development,staging,production

cmd/scan/scan.go

@@ -1,6 +1,7 @@
 package scan
 
 import (
+	"flag"
 	"fmt"
 
 	"github.com/kubescape/k8s-interface/k8sinterface"
@@ -97,6 +98,9 @@ func GetScanCommand(ks meta.IKubescape) *cobra.Command {
 	scanCmd.PersistentFlags().MarkHidden("silent")         // this flag should be deprecated since we added the --logger support
 	// scanCmd.PersistentFlags().MarkHidden("format-version") // meant for testing different output approaches and not for common use
 
+	// Retrieve --kubeconfig flag from https://github.com/kubernetes/kubectl/blob/master/pkg/cmd/cmd.go
+	scanCmd.PersistentFlags().AddGoFlag(flag.Lookup("kubeconfig"))
+
 	hostF := scanCmd.PersistentFlags().VarPF(&scanInfo.HostSensorEnabled, "enable-host-scan", "", "Deploy ARMO K8s host-sensor daemonset in the scanned cluster. Deleting it right after we collecting the data. Required to collect valuable data from cluster nodes for certain controls. Yaml file: https://github.com/kubescape/kubescape/blob/master/core/pkg/hostsensorutils/hostsensor.yaml")
 	hostF.NoOptDefVal = "true"
 	hostF.DefValue = "false, for no TTY in stdin"