Network.DNS.Resolver

DNS Resolver and lookup functions.

Sample code:

    import qualified Network.DNS as DNS (lookup)
    import Network.DNS hiding (lookup)
    main :: IO ()
    main = do
        rs <- makeResolvSeed defaultResolvConf
        withResolver rs $ \resolver -> do
            DNS.lookup resolver "www.example.com" A >>= print

Documentation

Configuration for resolver

data FileOrNumericHost

Union type for FilePath and HostName. Specify FilePath to "resolv.conf" or numeric IP address in String form.

Constructors

RCFilePath FilePath

RCHostName HostName

data ResolvConf

Type for resolver configuration

Constructors

ResolvConf

Fields

resolvInfo :: FileOrNumericHost

resolvTimeout :: Int

resolvBufsize :: Int64

defaultResolvConf :: ResolvConf

Default ResolvConf. resolvInfo is RCFilePath "/etc/resolv.conf". resolvTimeout is 3,000,000 micro seconds. resolvBufsize is 512.

Intermediate data type for resolver

data ResolvSeed

Abstract data type of DNS Resolver seed

makeResolvSeed :: ResolvConf -> IO ResolvSeed

Making ResolvSeed from an IP address of a DNS cache server.

Type and function for resolver

data Resolver

Abstract data type of DNS Resolver

withResolver :: ResolvSeed -> (Resolver -> IO ()) -> IO ()

Giving a thread-safe Resolver to the function of the second argument. withResolver should be passed to forkIO.

Looking up functions

lookup :: Resolver -> Domain -> TYPE -> IO (Maybe [RDATA])

Looking up resource records of a domain.

lookupRaw :: Resolver -> Domain -> TYPE -> IO (Maybe DNSFormat)

Looking up a domain and returning an entire DNS Response.