src/CommandLine.hs

   1 {-# LANGUAGE DeriveDataTypeable #-}
   2
   3 module CommandLine (
   4   Args(..),
   5   get_args
   6   )
   7 where
   8
   9 import System.Console.CmdArgs (
  10   Data,
  11   Typeable,
  12   (&=),
  13   args,
  14   auto,
  15   cmdArgs,
  16   def,
  17   details,
  18   explicit,
  19   groupname,
  20   help,
  21   helpArg,
  22   modes,
  23   name,
  24   program,
  25   summary,
  26   typ,
  27   versionArg )
  28
  29 -- Get the version from Cabal.
  30 import Paths_haeredes (version)
  31 import Data.Version (showVersion)
  32
  33 -- | Description of the 'NS' mode.
  34 ns_description :: String
  35 ns_description =
  36   "Confirm delegation of NS records. " ++
  37   "This is the default mode."
  38
  39 -- | Description of the 'MX' mode.
  40 mx_description :: String
  41 mx_description = "Confirm delegation of MX records."
  42
  43 program_name :: String
  44 program_name = "haeredes"
  45
  46 my_summary :: String
  47 my_summary = program_name ++ "-" ++ (showVersion version)
  48
  49 no_append_root_help :: String
  50 no_append_root_help =
  51   "Don't append a trailing dot to DNS names."
  52
  53 -- | Help string for the --server flag.
  54 server_help :: String
  55 server_help =
  56   "IP address or hostname of server to query " ++
  57   "(will use resolv.conf if not specified)."
  58
  59 -- | The Args type represents the possible command-line options. The
  60 --   duplication here seems necessary; CmdArgs' magic requires us to
  61 --   define some things explicitly.
  62 data Args =
  63   NS { no_append_root :: Bool,
  64        server :: Maybe String,
  65        delegates :: [String] } |
  66   MX { no_append_root :: Bool,
  67        server :: Maybe String,
  68        delegates :: [String] }
  69   deriving (Data, Show, Typeable)
  70
  71 arg_spec :: Args
  72 arg_spec =
  73   modes [ns &= auto, mx]
  74     &= program program_name
  75     &= summary my_summary
  76     &= helpArg [explicit,
  77                 name "help",
  78                 name "h",
  79                 groupname "Common flags"]
  80     &= versionArg [explicit,
  81                    name "version",
  82                    name "v",
  83                    groupname "Common flags"]
  84   where
  85     -- The repetition here is necessary, some CmdArgs magic going on.
  86     ns :: Args
  87     ns = NS {
  88            no_append_root = def
  89                          &= groupname "Common flags"
  90                          &= help no_append_root_help,
  91
  92            server = def
  93                  &= groupname "Common flags"
  94                  &= typ "IP"
  95                  &= help server_help,
  96
  97            delegates = def
  98                     &= args
  99                     &= typ "DELEGATES" }
 100
 101             &= details [ns_description]
 102
 103     mx :: Args
 104     mx = MX {
 105            no_append_root = def
 106                          &= groupname "Common flags"
 107                          &= help no_append_root_help,
 108
 109            server = def
 110                  &= groupname "Common flags"
 111                  &= typ "IP"
 112                  &= help server_help,
 113
 114            delegates = def
 115                     &= args
 116                     &= typ "DELEGATES" }
 117
 118             &= details [mx_description]
 119
 120 get_args :: IO Args
 121 get_args = cmdArgs arg_spec