src/DNS.hs

   1 module DNS ( lookup_mxs )
   2 where
   3
   4 import Network.DNS (
   5   Domain,
   6   defaultResolvConf,
   7   lookupMX,
   8   makeResolvSeed,
   9   withResolver )
  10
  11 -- Slow since we create the resolver every time.
  12 lookup_mxs :: Domain -> IO [Domain]
  13 lookup_mxs domain = do
  14   default_rs <- makeResolvSeed defaultResolvConf
  15   withResolver default_rs $ \resolver -> do
  16     mxs <- lookupMX resolver domain
  17     return $ case mxs of
  18                Left  _     -> []
  19                Right pairs -> map fst pairs