add portable mode

Portable mode is a convenient way to share a single directory on demand

cmd/portable.go

@@ -0,0 +1,69 @@
+package cmd
+
+import (
+	"path/filepath"
+
+	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/service"
+	"github.com/spf13/cobra"
+)
+
+var (
+	directoryToServe    string
+	portableSFTPDPort   int
+	portableEnableSCP   bool
+	portableUsername    string
+	portablePassword    string
+	portablePublicKeys  []string
+	portablePermissions []string
+	portableCmd         = &cobra.Command{
+		Use:   "portable",
+		Short: "Serve a single directory",
+		Long: `To serve the current working directory with auto generated credentials simply use:
+
+sftpgo portable
+
+Please take a look at the usage below to customize the serving parameters`,
+		Run: func(cmd *cobra.Command, args []string) {
+			portableDir := directoryToServe
+			if !filepath.IsAbs(portableDir) {
+				portableDir, _ = filepath.Abs(portableDir)
+			}
+			service := service.Service{
+				ConfigDir:     defaultConfigDir,
+				ConfigFile:    defaultConfigName,
+				LogFilePath:   defaultLogFile,
+				LogMaxSize:    defaultLogMaxSize,
+				LogMaxBackups: defaultLogMaxBackup,
+				LogMaxAge:     defaultLogMaxAge,
+				LogCompress:   defaultLogCompress,
+				LogVerbose:    defaultLogVerbose,
+				Shutdown:      make(chan bool),
+				PortableMode:  1,
+				PortableUser: dataprovider.User{
+					Username:    portableUsername,
+					Password:    portablePassword,
+					PublicKeys:  portablePublicKeys,
+					Permissions: portablePermissions,
+					HomeDir:     portableDir,
+				},
+			}
+			if err := service.StartPortableMode(portableSFTPDPort, portableEnableSCP); err == nil {
+				service.Wait()
+			}
+		},
+	}
+)
+
+func init() {
+	portableCmd.Flags().StringVarP(&directoryToServe, "directory", "d", ".",
+		"Path to the directory to serve. This can be an absolute path or a path relative to the current directory")
+	portableCmd.Flags().IntVarP(&portableSFTPDPort, "sftpd-port", "s", 0, "0 means a random non privileged port")
+	portableCmd.Flags().BoolVarP(&portableEnableSCP, "scp", "", false, "Enable SCP")
+	portableCmd.Flags().StringVarP(&portableUsername, "username", "u", "", "Leave empty to use an auto generated value")
+	portableCmd.Flags().StringVarP(&portablePassword, "password", "p", "", "Leave empty to use an auto generated value")
+	portableCmd.Flags().StringSliceVarP(&portablePublicKeys, "public-key", "k", []string{}, "")
+	portableCmd.Flags().StringSliceVarP(&portablePermissions, "permissions", "g", []string{"list", "download"},
+		"User's permissions. \"*\" means any permission")
+	rootCmd.AddCommand(portableCmd)
+}