{- arch-tag: Generic Server Support Copyright (C) 2004 John Goerzen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA -} {- | Module : Network.SocketServer Copyright : Copyright (C) 2004-2006 John Goerzen License : GNU GPL, version 2 or above Maintainer : John Goerzen Stability : experimental Portability: systems with networking This module provides an infrastructure to simplify server design. Written by John Goerzen, jgoerzen\@complete.org Please note: this module is designed to work with TCP, UDP, and Unix domain sockets, but only TCP sockets have been tested to date. This module is presently under-documented. For an example of usage, please see the description of "Network.FTP.Server". -} module Network.SocketServer(-- * Generic Options and Types InetServerOptions(..), simpleTCPOptions, SocketServer(..), HandlerT, -- * TCP server convenient setup serveTCPforever, -- * Lower-Level Processing setupSocketServer, handleOne, serveForever, closeSocketServer, -- * Combinators loggingHandler, threadedHandler, handleHandler ) where import Network.Socket import Network.BSD import Network.Utils import Control.Concurrent import System.IO import qualified System.Log.Logger {- | Options for your server. -} data InetServerOptions = InetServerOptions {listenQueueSize :: Int, portNumber :: PortNumber, interface :: HostAddress, reuse :: Bool, family :: Family, sockType :: SocketType, protoStr :: String } deriving (Eq, Show) {- | The main handler type. The first parameter is the socket itself. The second is the address of the remote endpoint. The third is the address of the local endpoint. -} type HandlerT = Socket -> SockAddr -> SockAddr -> IO () {- | Get Default options. You can always modify it later. -} simpleTCPOptions :: Int -- ^ Port Number -> InetServerOptions simpleTCPOptions p = InetServerOptions {listenQueueSize = 5, portNumber = (fromIntegral p), interface = iNADDR_ANY, reuse = False, family = AF_INET, sockType = Stream, protoStr = "tcp" } data SocketServer = SocketServer {optionsSS :: InetServerOptions, sockSS :: Socket} deriving (Eq, Show) {- | Takes some options and sets up the 'SocketServer'. I will bind and begin listening, but will not accept any connections itself. -} setupSocketServer :: InetServerOptions -> IO SocketServer setupSocketServer opts = do proto <- getProtocolNumber (protoStr opts) s <- socket (family opts) (sockType opts) proto setSocketOption s ReuseAddr (case (reuse opts) of True -> 1 False -> 0) bindSocket s (SockAddrInet (portNumber opts) (interface opts)) listen s (listenQueueSize opts) return $ SocketServer {optionsSS = opts, sockSS = s} {- | Close the socket server. Does not terminate active handlers, if any. -} closeSocketServer :: SocketServer -> IO () closeSocketServer ss = sClose (sockSS ss) {- | Handle one incoming request from the given 'SocketServer'. -} handleOne :: SocketServer -> HandlerT -> IO () handleOne ss func = let opts = (optionsSS ss) in do a <- accept (sockSS ss) localaddr <- getSocketName (fst a) func (fst a) (snd a) localaddr {- | Handle all incoming requests from the given 'SocketServer'. -} serveForever :: SocketServer -> HandlerT -> IO () serveForever ss func = sequence_ (repeat (handleOne ss func)) {- | Convenience function to completely set up a TCP 'SocketServer' and handle all incoming requests. This function is literally this: >serveTCPforever options func = > do sockserv <- setupSocketServer options > serveForever sockserv func -} serveTCPforever :: InetServerOptions -- ^ Server options -> HandlerT -- ^ Handler function -> IO () serveTCPforever options func = do sockserv <- setupSocketServer options serveForever sockserv func ---------------------------------------------------------------------- -- Combinators ---------------------------------------------------------------------- {- | Log each incoming connection using the interface in "System.Log.Logger". Log when the incoming connection disconnects. Also, log any failures that may occur in the child handler. -} loggingHandler :: String -- ^ Name of logger to use -> System.Log.Logger.Priority -- ^ Priority of logged messages -> HandlerT -- ^ Handler to call after logging -> HandlerT -- ^ Resulting handler loggingHandler hname prio nexth socket r_sockaddr l_sockaddr = do sockStr <- showSockAddr r_sockaddr System.Log.Logger.logM hname prio ("Received connection from " ++ sockStr) System.Log.Logger.traplogging hname System.Log.Logger.WARNING "" (nexth socket r_sockaddr l_sockaddr) System.Log.Logger.logM hname prio ("Connection " ++ sockStr ++ " disconnected") -- | Handle each incoming connection in its own thread to -- make the server multi-tasking. threadedHandler :: HandlerT -- ^ Handler to call in the new thread -> HandlerT -- ^ Resulting handler threadedHandler nexth socket r_sockaddr l_sockaddr= do forkIO (nexth socket r_sockaddr l_sockaddr) return () {- | Give your handler function a Handle instead of a Socket. The Handle will be opened with ReadWriteMode (you use one handle for both directions of the Socket). Also, it will be initialized with LineBuffering. Unlike other handlers, the handle will be closed when the function returns. Therefore, if you are doing threading, you should to it before you call this handler. -} handleHandler :: (Handle -> SockAddr -> SockAddr -> IO ()) -- ^ Handler to call -> HandlerT handleHandler func socket r_sockaddr l_sockaddr = do h <- socketToHandle socket ReadWriteMode hSetBuffering h LineBuffering func h r_sockaddr l_sockaddr hClose h