src/CommandLine.hs

   1 -- | Parse the command-line options, and display help text if
   2 --   necessary.
   3 module CommandLine (
   4   get_args )
   5 where
   6
   7 import System.Console.CmdArgs (
   8   (&=),
   9   cmdArgs,
  10   def,
  11   details,
  12   help,
  13   program,
  14   summary,
  15   typ,
  16   typDir )
  17
  18 -- This let's us get the version from Cabal.
  19 import Paths_htsn (version)
  20 import Data.Version (showVersion)
  21
  22 import OptionalConfiguration (OptionalConfiguration(..))
  23
  24
  25 -- | The description of the program, displayed as part of the help.
  26 description :: String
  27 description = "Parse XML files from The Sports Network feed."
  28
  29 -- | The name of this program.
  30 program_name :: String
  31 program_name = "htsn"
  32
  33 -- | A summary string output as part of the help.
  34 my_summary :: String
  35 my_summary = program_name ++ "-" ++ (showVersion version)
  36
  37
  38 -- | A description of the "password" option.
  39 password_help :: String
  40 password_help =
  41   "Password to use when connecting to the feed"
  42
  43 -- | A description of the "output_directory" option.
  44 output_directory_help :: String
  45 output_directory_help =
  46   "Directory in which to output the XML files; must be writable"
  47
  48 -- | A description of the "username" option.
  49 username_help :: String
  50 username_help =
  51   "Username to use when connecting to the feed"
  52
  53 -- | A data structure representing the possible command-line
  54 --   options. The CmdArgs library is doing heavy magic beneath the
  55 --   hood here.
  56 arg_spec :: OptionalConfiguration
  57 arg_spec =
  58   OptionalConfiguration {
  59     password         = def &= typ "PASSWORD" &= help password_help,
  60     output_directory = def &= typDir         &= help output_directory_help,
  61     username         = def &= typ "USERNAME" &= help username_help,
  62     feed_hosts       = def &= typ "HOSTNAMES" }
  63   &= program program_name
  64   &= summary my_summary
  65   &= details [description]
  66
  67
  68 -- | A convenience function; our only export. Meant to be used in
  69 --   'main' to retrieve the command-line arguments.
  70 get_args :: IO OptionalConfiguration
  71 get_args = cmdArgs arg_spec