src/CommandLine.hs

   1 -- | Parse the command-line options, and display help text if
   2 --   necessary.
   3 --
   4 module CommandLine (
   5   get_args )
   6 where
   7
   8 -- System imports.
   9 import System.Console.CmdArgs (
  10   (&=),
  11   args,
  12   cmdArgs,
  13   def,
  14   details,
  15   help,
  16   program,
  17   summary,
  18   typ,
  19   typFile )
  20 import Paths_htsn_import ( version ) -- These let us get the
  21 import Data.Version ( showVersion )  -- version from Cabal.
  22
  23 -- Local imports.
  24 import OptionalConfiguration ( OptionalConfiguration(..) )
  25
  26
  27 -- | The description of the program, displayed as part of the help.
  28 description :: String
  29 description = "Import XML files from The Sports Network into an RDBMS."
  30
  31
  32 -- | The name of this program.
  33 program_name :: String
  34 program_name = "htsn-import"
  35
  36
  37 -- | A summary string output as part of the help.
  38 my_summary :: String
  39 my_summary = program_name ++ "-" ++ (showVersion version)
  40
  41
  42 -- | A description of the "backend" option.
  43 backend_help :: String
  44 backend_help =
  45   "Database choice, either \"Sqlite\" or \"Postgres\"."
  46
  47
  48 -- | A description of the "connection_string" option.
  49 connection_string_help :: String
  50 connection_string_help =
  51   "A database-specific connection string (depends on the backend)."
  52
  53
  54 -- | A description of the "log_file" option.
  55 log_file_help :: String
  56 log_file_help =
  57   "Log to the given file."
  58
  59
  60 -- | A description of the "log_level" option.
  61 log_level_help :: String
  62 log_level_help =
  63   "How verbose should the logs be? One of INFO, WARNING, ERROR."
  64
  65
  66 -- | A description of the "remove" option.
  67 remove_help :: String
  68 remove_help =
  69   "Remove files that have been successfully imported."
  70
  71
  72 -- | A description of the "syslog" option.
  73 syslog_help :: String
  74 syslog_help =
  75   "Enable logging to syslog."
  76
  77
  78 -- | A data structure representing the possible command-line
  79 --   options. The CmdArgs library is doing heavy magic beneath the
  80 --   hood here.
  81 --
  82 arg_spec :: OptionalConfiguration
  83 arg_spec =
  84   OptionalConfiguration {
  85     backend           = def &= typ "BACKEND"  &= help backend_help,
  86     connection_string = def &= typ "STRING"   &= help connection_string_help,
  87     log_file          = def &= typFile        &= help log_file_help,
  88     log_level         = def &= typ "LEVEL"    &= help log_level_help,
  89     remove            = def &= typ "BOOL"     &= help remove_help,
  90     syslog            = def &= typ "BOOL"     &= help syslog_help,
  91     xml_files         = def &= typ "XMLFILES" &= args }
  92   &= program program_name
  93   &= summary my_summary
  94   &= details [description]
  95
  96
  97 -- | A convenience function; our only export. Meant to be used in
  98 --   'main' to retrieve the command-line arguments.
  99 --
 100 get_args :: IO OptionalConfiguration
 101 get_args = cmdArgs arg_spec