cmd/kgctl: use KUBECONFIG from env

README.md

@@ -99,7 +99,7 @@ EOF
 This configuration can then be applied to a local WireGuard interface, e.g. `wg0`, with the help of the `kgctl` tool:
 
 ```shell
-kgctl --kubeconfig=$KUBECONFIG showconf peer squat > peer.ini
+kgctl showconf peer squat > peer.ini
 sudo wg setconf wg0 peer.ini
 ```
 
@@ -111,7 +111,7 @@ The topology of a Kilo network can be analyzed using the `kgctl` binary.
 For example, the `graph` command can be used to generate a graph of the network in Graphviz format:
 
 ```shell
-kgctl graph --kubeconfig=$KUBECONFIG | twopi -Tsvg > cluster.svg
+kgctl graph | twopi -Tsvg > cluster.svg
 ```
 
 <img src="./cluster.svg">

cmd/kgctl/main.go

@@ -116,7 +116,7 @@ func main() {
 	}
 	cmd.PersistentFlags().StringVar(&backend, "backend", k8s.Backend, fmt.Sprintf("The backend for the mesh. Possible values: %s", availableBackends))
 	cmd.PersistentFlags().StringVar(&granularity, "mesh-granularity", string(mesh.DataCenterGranularity), fmt.Sprintf("The granularity of the network mesh to create. Possible values: %s", availableGranularities))
-	cmd.PersistentFlags().StringVar(&kubeconfig, "kubeconfig", "", "Path to kubeconfig.")
+	cmd.PersistentFlags().StringVar(&kubeconfig, "kubeconfig", os.Getenv("KUBECONFIG"), "Path to kubeconfig.")
 	cmd.PersistentFlags().StringVar(&subnet, "subnet", "10.4.0.0/16", "CIDR from which to allocate addressees to WireGuard interfaces.")
 
 	for _, subCmd := range []*cobra.Command{

docs/vpn.md

@@ -31,7 +31,7 @@ Now, the `kgctl` tool can be used to generate the WireGuard configuration for th
 
 ```shell
 PEER=squat
-kgctl --kubeconfig=$KUBECONFIG showconf peer $PEER
+kgctl showconf peer $PEER
 ```
 
 This will produce some output like:
@@ -47,7 +47,7 @@ The configuration can then be applied to a local WireGuard interface, e.g. `wg0`
 
 ```shell
 IFACE=wg0
-kgctl --kubeconfig=$KUBECONFIG showconf peer $PEER > peer.ini
+kgctl showconf peer $PEER > peer.ini
 sudo wg setconf $IFACE peer.ini
 ```
 
@@ -55,7 +55,7 @@ Finally, in order to access the cluster, the client will need appropriate routes
 For example, on a Linux machine, the creation of these routes could be automated by running:
 
 ```shell
-for ip in $(kgctl --kubeconfig=$KUBECONFIG showconf peer $PEER | grep AllowedIPs | cut -f 3- -d ' ' | tr -d ','); do
+for ip in $(kgctl showconf peer $PEER | grep AllowedIPs | cut -f 3- -d ' ' | tr -d ','); do
 	sudo ip route add $ip dev $IFACE
 done
 ```