redone backend handling and config parsing

app/Backend/Backend.hs

@@ -0,0 +1,39 @@
+module Backend.Backend where
+  
+import Control.Concurrent.MVar
+import qualified Network.Wai as Wai
+
+#ifdef HTTP_SUPPORT
+import qualified Backend.Http as HTTP
+#endif
+#ifdef HTTPS_SUPPORT
+import qualified Backend.Https as HTTPS
+#endif
+
+-- maybe we want a String instead of T.Text depends on
+-- the argument parser
+
+-- A backend consists of three things, The backend action, a Text to be
+-- used as the command line option Flag, and a Bool if it has a config file.
+--
+-- The backend action must be non blocking and fork the backend, the returned
+-- list of MVar is there to communicate the termination of the backend. (The main
+-- threat will wait till all MVar are present (not neccesarry at once)).
+-- The action takes two parameter, the application the backend should run and
+-- the path of the config File. If the Bool is False there are no guarantees on the FilePath
+-- and the action should not try to evaluate the FilePath.
+-- type Backend = (Wai.Application -> FilePath -> IO [MVar ()],T.Text,Bool)
+
+data Backend =
+  BackendWithConfig (Wai.Application -> FilePath -> IO [MVar ()]) String String
+  | BackendWithoutConfig (Wai.Application -> IO [MVar ()]) String String
+
+backends :: [Backend]
+backends =
+#ifdef HTTP_SUPPORT
+  BackendWithConfig HTTP.forkHttpBackend "http" "Host as a simple http server, using Warp" :
+#endif
+#ifdef HTTPS_SUPPORT
+  BackendWithConfig HTTPS.forkHttpsBackend "https" "Host as as simple https server, using Warp" :
+#endif
+  []