Safe Haskell	None
Language	Haskell2010

Network.Mux.Channel

Description

An extension of Channel, with additional Channel implementations.

Synopsis

data Channel (m :: Type -> Type) = Channel {
- send :: ByteString -> m ()
- recv :: m (Maybe ByteString)
}
createBufferConnectedChannels :: MonadSTM m => m (Channel m, Channel m)
createPipeConnectedChannels :: IO (Channel IO, Channel IO)
createSocketConnectedChannels :: Family -> IO (Channel IO, Channel IO)
withFifosAsChannel :: FilePath -> FilePath -> (Channel IO -> IO a) -> IO a
socketAsChannel :: Socket -> Channel IO
channelEffect :: Monad m => (ByteString -> m ()) -> (Maybe ByteString -> m ()) -> Channel m -> Channel m
delayChannel :: forall (m :: Type -> Type). MonadDelay m => DiffTime -> Channel m -> Channel m
loggingChannel :: forall (m :: Type -> Type) id. (MonadSay m, Show id) => id -> Channel m -> Channel m

Documentation

data Channel (m :: Type -> Type) Source #

Constructors

Channel
Fields send :: ByteString -> m () Write bytes to the channel. It maybe raise exceptions. recv :: m (Maybe ByteString) Read some input from the channel, or `Nothing` to indicate EOF. Note that having received EOF it is still possible to send. The EOF condition is however monotonic. It may raise exceptions (as appropriate for the monad and kind of channel).

createBufferConnectedChannels :: MonadSTM m => m (Channel m, Channel m) Source #

Create a pair of Channels that are connected internally.

This is intended for inter-thread communication, such as between a multiplexing thread and a thread running a peer.

It uses lazy ByteStrings but it ensures that data written to the channel is fully evaluated first. This ensures that any work to serialise the data takes place on the writer side and not the reader side.

createPipeConnectedChannels :: IO (Channel IO, Channel IO) Source #

Create a local pipe, with both ends in this process, and expose that as a pair of Channels, one for each end.

This is primarily for testing purposes since it does not allow actual IPC.

createSocketConnectedChannels Source #

Arguments

:: Family	Usually AF_UNIX or AF_INET
-> IO (Channel IO, Channel IO)

withFifosAsChannel Source #

Arguments

:: FilePath	FIFO for reading
-> FilePath	FIFO for writing
-> (Channel IO -> IO a)
-> IO a

Open a pair of Unix FIFOs, and expose that as a Channel.

The peer process needs to open the same files but the other way around, for writing and reading.

This is primarily for the purpose of demonstrations that use communication between multiple local processes. It is Unix specific.

socketAsChannel :: Socket -> Channel IO Source #

Make a Channel from a Socket. The socket must be a stream socket

channelEffect Source #

Arguments

:: Monad m
=> (ByteString -> m ())	Action before `send`
-> (Maybe ByteString -> m ())	Action after `recv`
-> Channel m
-> Channel m

delayChannel :: forall (m :: Type -> Type). MonadDelay m => DiffTime -> Channel m -> Channel m Source #

Delay a channel on the receiver end.

This is intended for testing, as a crude approximation of network delays. More accurate models along these lines are of course possible.

loggingChannel :: forall (m :: Type -> Type) id. (MonadSay m, Show id) => id -> Channel m -> Channel m Source #

Channel which logs sent and received messages.