Network.SocketServer

MissingH-1.1.1.0: Large utility library

Portability | systems with networking
Stability | experimental
Maintainer | John Goerzen <jgoerzen@complete.org>

Network.SocketServer

Contents

- Generic Options and Types
- TCP server convenient setup
- Lower-Level Processing
- Combinators

Description

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.

Synopsis

- data InetServerOptions = InetServerOptions {
  - listenQueueSize :: Int
  - portNumber :: PortNumber
  - interface :: HostAddress
  - reuse :: Bool
  - family :: Family
  - sockType :: SocketType
  - protoStr :: String
  }
- simpleTCPOptions :: Int -> InetServerOptions
- data SocketServer = SocketServer {
  - optionsSS :: InetServerOptions
  - sockSS :: Socket
  }
- type HandlerT = Socket -> SockAddr -> SockAddr -> IO ()
- serveTCPforever :: InetServerOptions -> HandlerT -> IO ()
- setupSocketServer :: InetServerOptions -> IO SocketServer
- handleOne :: SocketServer -> HandlerT -> IO ()
- serveForever :: SocketServer -> HandlerT -> IO ()
- closeSocketServer :: SocketServer -> IO ()
- loggingHandler :: String -> Priority -> HandlerT -> HandlerT
- threadedHandler :: HandlerT -> HandlerT
- handleHandler :: (Handle -> SockAddr -> SockAddr -> IO ()) -> HandlerT

# Generic Options and Types

data InetServerOptions

Options for your server.

Constructors

InetServerOptions |
Fields listenQueueSize :: Int portNumber :: PortNumber interface :: HostAddress reuse :: Bool family :: Family sockType :: SocketType protoStr :: String

Instances

Eq InetServerOptions |
Show InetServerOptions |

simpleTCPOptions

Arguments

:: Int | Port Number
-> InetServerOptions |

Get Default options. You can always modify it later.

data SocketServer

Constructors

SocketServer |
Fields optionsSS :: InetServerOptions sockSS :: Socket

Instances

Eq SocketServer |
Show SocketServer |

type HandlerT = Socket -> SockAddr -> SockAddr -> IO ()

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.

# TCP server convenient setup

serveTCPforever

Arguments

:: InetServerOptions | Server options
-> HandlerT | Handler function
-> IO () |

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

# Lower-Level Processing

setupSocketServer :: InetServerOptions -> IO SocketServer

Takes some options and sets up the `SocketServer`. I will bind and begin listening, but will not accept any connections itself.

handleOne :: SocketServer -> HandlerT -> IO ()

Handle one incoming request from the given `SocketServer`.

serveForever :: SocketServer -> HandlerT -> IO ()

Handle all incoming requests from the given `SocketServer`.

closeSocketServer :: SocketServer -> IO ()

Close the socket server. Does not terminate active handlers, if any.

# Combinators

loggingHandler

Arguments

:: String | Name of logger to use
-> Priority | Priority of logged messages
-> HandlerT | Handler to call after logging
-> HandlerT | Resulting handler

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.

threadedHandler

Arguments

:: HandlerT | Handler to call in the new thread
-> HandlerT | Resulting handler

Handle each incoming connection in its own thread to make the server multi-tasking.

handleHandler

Arguments

:: (Handle -> SockAddr -> SockAddr -> IO ()) | Handler to call
-> HandlerT |

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.