-
--- | Perform query and return error string or parsed domain object
-queryNmcDom ::
- (String -> IO (Either String ByteString)) -- ^ query operation action
- -> String -- ^ key
- -> IO (Either String NmcDom) -- ^ error string or domain
-queryNmcDom queryOp key = do
- l <- queryOp key
- case l of
- Left estr -> return $ Left estr
- Right str -> case decode str :: Maybe NmcDom of
- Nothing -> return $ Left $ "Unparseable value: " ++ (show str)
- Just dom -> return $ Right dom
-
--- | Try to fetch "import" object and merge it into the base domain
--- Original "import" element is removed, but new imports from the
--- imported objects are processed recursively until there are none.
-mergeImport ::
- (String -> IO (Either String ByteString)) -- ^ query operation action
- -> Int -- ^ recursion counter
- -> NmcDom -- ^ base domain
- -> IO (Either String NmcDom) -- ^ result with merged import
-mergeImport queryOp depth base = do
- let
- mbase = mergeSelf base
- base' = mbase {domImport = Nothing}
- -- print base
- if depth <= 0 then return $ Left "Nesting of imports is too deep"
- else case domImport mbase of
- Nothing -> return $ Right base'
- Just key -> do
- sub <- queryNmcDom queryOp key
- case sub of
- Left e -> return $ Left e
- Right sub' -> mergeImport queryOp (depth - 1) $ sub' `merge` base'
-
--- | If there is an element in the map with key "", merge the contents
--- and remove this element. Do this recursively.
-mergeSelf :: NmcDom -> NmcDom
-mergeSelf base =
- let
- map = domMap base
- base' = base {domMap = removeSelf map}
- removeSelf Nothing = Nothing
- removeSelf (Just map) = if size map' == 0 then Nothing else Just map'
- where map' = M.delete "" map
- in
- case map of
- Nothing -> base'
- Just map' ->
- case M.lookup "" map' of
- Nothing -> base'
- Just sub -> (mergeSelf sub) `merge` base'
- -- recursion depth limited by the size of the record
-
--- | SRV case - remove everyting and filter SRV records
-normalizeSrv :: String -> String -> NmcDom -> NmcDom
-normalizeSrv serv proto dom =
- emptyNmcDom {domService = fmap (filter needed) (domService dom)}
- where
- needed r = srvName r == serv && srvProto r == proto
-
--- | Presence of some elements require removal of some others
-normalizeDom :: NmcDom -> NmcDom
-normalizeDom dom = foldr id dom [ srvNormalizer
- , translateNormalizer
- , nsNormalizer
- ]
- where
- nsNormalizer dom = case domNs dom of
- Nothing -> dom
- Just ns -> emptyNmcDom { domNs = domNs dom, domEmail = domEmail dom }
- translateNormalizer dom = case domTranslate dom of
- Nothing -> dom
- Just tr -> dom { domMap = Nothing }
- srvNormalizer dom = dom { domService = Nothing, domMx = makemx }
- where
- makemx = case domService dom of
- Nothing -> Nothing
- Just svl -> Just $ map makerec (filter needed svl)
- where
- needed sr = srvName sr == "smtp"
- && srvProto sr == "tcp"
- && srvPort sr == 25
- makerec sr = (show (srvPrio sr)) ++ " " ++ (srvHost sr)
-
--- | Merge imports and Selfs and follow the maps tree to get dom
-descendNmcDom ::
- (String -> IO (Either String ByteString)) -- ^ query operation action
- -> [String] -- ^ subdomain chain
- -> NmcDom -- ^ base domain
- -> IO (Either String NmcDom) -- ^ fully processed result
-descendNmcDom queryOp subdom base = do
- base' <- mergeImport queryOp 10 base
- case subdom of
- [] -> return $ fmap normalizeDom base'
- -- A hack to handle SRV records: don't descend if ["_prot","_serv"]
- [('_':p),('_':s)] -> return $ fmap (normalizeSrv s p) base'
- d:ds ->
- case base' of
- Left err -> return base'
- Right base'' ->
- case domMap base'' of
- Nothing -> return $ Right emptyNmcDom
- Just map ->
- case M.lookup d map of
- Nothing -> return $ Right emptyNmcDom
- Just sub -> descendNmcDom queryOp ds sub
-
--- | Initial NmcDom populated with "import" only, suitable for "descend"
-seedNmcDom ::
- String -- ^ domain key (without namespace prefix)
- -> NmcDom -- ^ resulting seed domain
-seedNmcDom dn = emptyNmcDom { domImport = Just ("d/" ++ dn)}