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   args,
  10   cmdArgs,
  11   def,
  12   details,
  13   help,
  14   program,
  15   summary,
  16   typ,
  17   typFile,
  18   typDir )
  19
  20 -- This let's us get the version from Cabal.
  21 import Paths_htsn (version)
  22 import Data.Version (showVersion)
  23
  24 import OptionalConfiguration ( OptionalConfiguration(..) )
  25
  26 -- | The description of the program, displayed as part of the help.
  27 description :: String
  28 description = "Parse XML files from The Sports Network feed."
  29
  30 -- | The name of this program.
  31 program_name :: String
  32 program_name = "htsn"
  33
  34 -- | A summary string output as part of the help.
  35 my_summary :: String
  36 my_summary = program_name ++ "-" ++ (showVersion version)
  37
  38
  39 daemonize_help :: String
  40 daemonize_help =
  41   "Run as a daemon, in the background."
  42
  43 -- | A description of the "log_file" option.
  44 log_file_help :: String
  45 log_file_help =
  46   "Log to the given file."
  47
  48 log_level_help :: String
  49 log_level_help =
  50   "How verbose should the logs be? One of INFO, WARNING, ERROR."
  51
  52 -- | A description of the "output_directory" option.
  53 output_directory_help :: String
  54 output_directory_help =
  55   "Directory in which to output the XML files; must be writable"
  56
  57 -- | A description of the "password" option.
  58 password_help :: String
  59 password_help =
  60   "Password to use when connecting to the feed"
  61
  62 pidfile_help :: String
  63 pidfile_help =
  64   "Location to create PID file (daemon only)."
  65
  66 run_as_group_help :: String
  67 run_as_group_help =
  68   "System group to run as (daemon only)."
  69
  70 run_as_user_help :: String
  71 run_as_user_help =
  72   "System user to run under (daemon only)."
  73
  74 -- | A description of the "syslog" option.
  75 syslog_help :: String
  76 syslog_help =
  77   "Enable logging to syslog."
  78
  79 -- | A description of the "username" option.
  80 username_help :: String
  81 username_help =
  82   "Username to use when connecting to the feed"
  83
  84 -- | A data structure representing the possible command-line
  85 --   options. The CmdArgs library is doing heavy magic beneath the
  86 --   hood here.
  87 arg_spec :: OptionalConfiguration
  88 arg_spec =
  89   OptionalConfiguration {
  90     -- Use an empty list for feed_hosts since cmdargs will appends to
  91     -- the default when the user supplies feed hosts. If he specifies
  92     -- any, those are all we should use.
  93     daemonize        = def &= typ "BOOL"      &= help daemonize_help,
  94     feed_hosts       = def &= typ "HOSTNAMES" &= args,
  95     log_file         = def &= typFile         &= help log_file_help,
  96     log_level        = def &= typ "LEVEL"     &= help log_level_help,
  97     output_directory = def &= typDir          &= help output_directory_help,
  98     password         = def &= typ "PASSWORD"  &= help password_help,
  99     pidfile          = def &= typFile         &= help pidfile_help,
 100     run_as_group     = def &= typ "GROUP"     &= help run_as_group_help,
 101     run_as_user      = def &= typ "USER"      &= help run_as_user_help,
 102     syslog           = def &= typ "BOOL"      &= help syslog_help,
 103     username         = def &= typ "USERNAME"  &= help username_help }
 104   &= program program_name
 105   &= summary my_summary
 106   &= details [description]
 107
 108
 109 -- | A convenience function; our only export. Meant to be used in
 110 --   'main' to retrieve the command-line arguments.
 111 get_args :: IO OptionalConfiguration
 112 get_args = cmdArgs arg_spec