-- | This module defines the 'Configuration' type, which is just a
-- wrapper around all of the configuration options we accept on the
--- command line. We thread this throughout the rest of the program.
-
+-- command line.
+--
module Configuration (
Configuration(..),
merge_optional )
where
-import System.Console.CmdArgs.Default (Default(..))
+import System.Console.CmdArgs.Default ( Default(..) )
+import System.Log ( Priority( INFO ) )
+import qualified OptionalConfiguration as OC (
+ OptionalConfiguration(..),
+ merge_maybes )
import FeedHosts (FeedHosts(..))
-import qualified OptionalConfiguration as OC (OptionalConfiguration(..))
+-- | The main configuration data type. This will be passed to most of
+-- the important functions once it has been created.
data Configuration =
Configuration {
+ daemonize :: Bool,
feed_hosts :: FeedHosts,
- password :: String,
+ log_file :: Maybe FilePath,
+ log_level :: Priority,
output_directory :: FilePath,
+ password :: String,
+ pidfile :: FilePath,
+ run_as_group :: Maybe String,
+ run_as_user :: Maybe String,
+ syslog :: Bool,
username :: String }
deriving (Show)
-- | A Configuration with all of its fields set to their default
-- values.
instance Default Configuration where
- def = Configuration def def "." def
+ def = Configuration {
+ daemonize = def,
+ feed_hosts = def,
+ log_file = def,
+ log_level = INFO,
+ output_directory = ".",
+ password = def,
+ pidfile = "/run/htsn/htsn.pid",
+ run_as_group = def,
+ run_as_user = def,
+ syslog = def,
+ username = def }
+
+-- | Merge a Configuration with an OptionalConfiguration. This is more
+-- or less the Monoid instance for OptionalConfiguration, but since
+-- the two types are different, we have to repeat ourselves.
merge_optional :: Configuration
-> OC.OptionalConfiguration
-> Configuration
merge_optional cfg opt_cfg =
Configuration
+ (merge (daemonize cfg) (OC.daemonize opt_cfg))
all_feed_hosts
- (merge (password cfg) (OC.password opt_cfg))
+ (OC.merge_maybes (log_file cfg) (OC.log_file opt_cfg))
+ (merge (log_level cfg) (OC.log_level opt_cfg))
(merge (output_directory cfg) (OC.output_directory opt_cfg))
+ (merge (password cfg) (OC.password opt_cfg))
+ (merge (pidfile cfg) (OC.pidfile opt_cfg))
+ (OC.merge_maybes (run_as_group cfg) (OC.run_as_group opt_cfg))
+ (OC.merge_maybes (run_as_user cfg) (OC.run_as_user opt_cfg))
+ (merge (syslog cfg) (OC.syslog opt_cfg))
(merge (username cfg) (OC.username opt_cfg))
where
+ -- | If the thing on the right is Just something, return that
+ -- something, otherwise return the thing on the left.
merge :: a -> Maybe a -> a
merge x Nothing = x
merge _ (Just y) = y
-- If there are any optional usernames, use only those.
all_feed_hosts = if (null (get_feed_hosts (OC.feed_hosts opt_cfg)))
- then (feed_hosts cfg)
- else (OC.feed_hosts opt_cfg)
+ then (feed_hosts cfg)
+ else (OC.feed_hosts opt_cfg)