HTTP-4000.0.7: A library for client-side HTTP

Portabilitynon-portable (not tested)
MaintainerSigbjorn Finne <>



Some utility functions for working with the Haskell network package. Mostly for internal use by the Network.HTTP code, but



data Connection Source

The Connection newtype is a wrapper that allows us to make connections an instance of the Stream class, without GHC extensions. While this looks sort of like a generic reference to the transport layer it is actually TCP specific, which can be seen in the implementation of the 'Stream Connection' instance.


openTCPPort :: String -> Int -> IO ConnectionSource

openTCPPort uri port establishes a connection to a remote host, using getHostByName which possibly queries the DNS system, hence may trigger a network connection.

isConnectedTo :: Connection -> String -> IO BoolSource

Checks both that the underlying Socket is connected and that the connection peer matches the given host name (which is recorded locally).

socketConnection :: BufferType ty => String -> Socket -> IO (HandleStream ty)Source

socketConnection, like openConnection but using a pre-existing Socket.

class BufferType bufType => HStream bufType whereSource

HStream overloads the use of HandleStreams, letting you overload the handle operations over the type that is communicated across the handle. It is used in the context of Network.HTTP to buy us freedom in how HTTP Request and Response payloads are represented.

The package provides instances for ByteStrings and String, but should you want to plug in your own payload representation, defining your own HStream instance is all it takes.


openStream :: String -> Int -> IO (HandleStream bufType)Source

openSocketStream :: String -> Socket -> IO (HandleStream bufType)Source

readLine :: HandleStream bufType -> IO (Result bufType)Source

readBlock :: HandleStream bufType -> Int -> IO (Result bufType)Source

writeBlock :: HandleStream bufType -> bufType -> IO (Result ())Source

close :: HandleStream bufType -> IO ()Source

data StreamHooks ty Source




hook_readLine :: (ty -> String) -> Result ty -> IO ()
hook_readBlock :: (ty -> String) -> Int -> Result ty -> IO ()
hook_writeBlock :: (ty -> String) -> ty -> Result () -> IO ()
hook_close :: IO ()


Eq ty => Eq (StreamHooks ty)