feat: add support for custom device hostname (#789)

Configure via --hostname (or -n) flag in the `up` and `login` commands
---------

Signed-off-by: Chinmay D. Pai <chinmay.pai@zerodha.com>

client/cmd/login.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/netbirdio/netbird/client/internal"
 	"github.com/netbirdio/netbird/client/proto"
+	"github.com/netbirdio/netbird/client/system"
 )
 
 var loginCmd = &cobra.Command{
@@ -32,6 +33,11 @@ var loginCmd = &cobra.Command{
 
 		ctx := internal.CtxInitState(context.Background())
 
+		if hostName != "" {
+			// nolint
+			ctx = context.WithValue(ctx, system.DeviceNameCtxKey, hostName)
+		}
+
 		// workaround to run without service
 		if logFile == "console" {
 			err = handleRebrand(cmd)

client/cmd/root.go

@@ -45,6 +45,7 @@ var (
 	managementURL           string
 	adminURL                string
 	setupKey                string
+	hostName                string
 	preSharedKey            string
 	natExternalIPs          []string
 	customDNSAddress        string
@@ -94,6 +95,7 @@ func init() {
 	rootCmd.PersistentFlags().StringVar(&logFile, "log-file", defaultLogFile, "sets Netbird log path. If console is specified the the log will be output to stdout")
 	rootCmd.PersistentFlags().StringVarP(&setupKey, "setup-key", "k", "", "Setup key obtained from the Management Service Dashboard (used to register peer)")
 	rootCmd.PersistentFlags().StringVar(&preSharedKey, "preshared-key", "", "Sets Wireguard PreSharedKey property. If set, then only peers that have the same key can communicate.")
+	rootCmd.PersistentFlags().StringVarP(&hostName, "hostname", "n", "", "Sets a custom hostname for the device")
 	rootCmd.AddCommand(serviceCmd)
 	rootCmd.AddCommand(upCmd)
 	rootCmd.AddCommand(downCmd)

client/cmd/up.go

@@ -15,6 +15,7 @@ import (
 	"github.com/netbirdio/netbird/client/internal"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/proto"
+	"github.com/netbirdio/netbird/client/system"
 	"github.com/netbirdio/netbird/util"
 )
 
@@ -55,6 +56,11 @@ func upFunc(cmd *cobra.Command, args []string) error {
 
 	ctx := internal.CtxInitState(cmd.Context())
 
+	if hostName != "" {
+		// nolint
+		ctx = context.WithValue(ctx, system.DeviceNameCtxKey, hostName)
+	}
+
 	if foregroundMode {
 		return runInForegroundMode(ctx, cmd)
 	}