feat(lms): random ident pw generation without db

src/Handler/Utils/LMS.hs

@@ -14,6 +14,7 @@ module Handler.Utils.LMS
   , csvFilenameLmsResult  
   , lmsUserToDelete, _lmsUserToDelete
   , lmsUserToDeleteExpr
+  , randomLMSIdent, randomLMSpw
   ) where
 
 -- general utils for LMS Interface Handlers
@@ -22,6 +23,10 @@ import Import
 import Handler.Utils
 import qualified Database.Esqueleto.Legacy as E
 
+import qualified Data.Text    as T
+import qualified Data.UUID    as UUID (toText) 
+import qualified Data.UUID.V4 as UUID (nextRandom)
+
 -- generic Column names 
 csvLmsIdent   :: IsString a => a
 csvLmsIdent = fromString "user" -- "Benutzerkennung"
@@ -83,3 +88,24 @@ lmsUserToDelete LmsUser{lmsUserEnded, lmsUserStatus} = isNothing lmsUserEnded &&
 _lmsUserToDelete :: Getter LmsUser Bool 
 _lmsUserToDelete = to lmsUserToDelete
 
+
+-- random generation of LmsIdentifiers, maybe this should be in Model.Types.Lms since length specifications are type-y?
+
+lengthIdent :: Int 
+lengthIdent = 8 
+
+lengthPassword :: Int 
+lengthPassword = 8 
+
+randomText :: MonadIO m => Int -> m Text 
+randomText n 
+  | n <=  8   = T.take n                     . UUID.toText <$> liftIO UUID.nextRandom
+  | n <= 32   = T.take n . T.filter ('-' ==) . UUID.toText <$> liftIO UUID.nextRandom
+  | otherwise = (<>) <$> randomText 32 <*> randomText (n - 32)
+
+randomLMSIdent :: MonadIO m => m LmsIdent 
+randomLMSIdent = LmsIdent <$> randomText lengthIdent
+
+randomLMSpw :: MonadIO m => m Text 
+randomLMSpw = randomText lengthPassword
+