.00title-haskell-udp.txt

.gitignore

.stack-work

Client.hs

module Main where

import Data.List(find)
import qualified Network.Socket  as S
import qualified Network.Socket.ByteString as SB
import qualified Data.ByteString.Char8 as C
import Data.Maybe
import Control.Monad (unless)

main :: IO ()
main = S.withSocketsDo client


hint = S.defaultHints { S.addrSocketType = S.Datagram, S.addrProtocol = 17}


host = "localhost"

client = do 
       info <- S.getAddrInfo (Just hint) (Just host) (Just "3000")
       let saddr =  find (\ i -> S.AF_INET == S.addrFamily i ) info
       unless ( isNothing saddr ) $ do
         sock <- S.socket (S.addrFamily $ fromJust saddr) S.Datagram S.defaultProtocol
         print $ S.addrAddress $ fromJust saddr
         SB.sendTo sock
                (C.pack "Hello, world!")
                (S.addrAddress $ fromJust saddr)
         msg <- SB.recv sock 1024
         S.close sock
         putStr "Received "
         C.putStrLn msg

DESCRIPTION.md

IPv4 IPv6の取扱について

socketのaddress family AF_UNSPECを用いるとv4/6を同じソケットで扱えるが serverのbindにaddrinfoを用いる方法がないため、v4決め打ちのコードで実装している。

いま、思いつく方法の一つはbind4 <|> bind6みたいにMonadPlusかなんかで 両方を実行して両方が失敗したときのみ例外を捕まえるやりかた。

あとは、network packageをどうにかしないと行けないと思う。

LICENSE

Copyright Kouichi Nakanishi (c) 2017

All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following
      disclaimer in the documentation and/or other materials provided
      with the distribution.

    * Neither the name of Kouichi Nakanishi nor the names of other
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Server.hs

{-# LANGUAGE OverloadedStrings #-}
module Main where

import qualified Control.Exception as E
import Network.Socket
import qualified Network.Socket.ByteString as B
import qualified Data.ByteString.Char8 as B8

port = 3000
maxline = 1024


main :: IO ()
main = withSocketsDo echoserver

echoserver :: IO ()
echoserver = do
  sockv4 <- socket AF_INET Datagram 0
  bind4 sockv4  `E.catch` (print :: E.SomeException -> IO())

  sockv6 <- socket AF_INET6 Datagram 0
  setSocketOption sockv6 IPv6Only 1  
  bind6 sockv6  `E.catch` (print :: E.SomeException -> IO ())
  echo sockv4

    where 
          bind4 s = bind s (SockAddrInet port iNADDR_ANY) 
          bind6 s = bind s (SockAddrInet6 port 0 (0,0,0,1) 0)


echo :: Socket -> IO ()
echo sock = do
  (mesg, client) <- B.recvFrom sock maxline
  B.sendTo sock ("resp:" `B8.append` mesg)  client
  close sock

Setup.hs

import Distribution.Simple
main = defaultMain

stack.yaml

# This file was automatically generated by 'stack init'
#
# Some commonly used options have been documented as comments in this file.
# For advanced use and comprehensive documentation of the format, please see:
# http://docs.haskellstack.org/en/stable/yaml_configuration/

# Resolver to choose a 'specific' stackage snapshot or a compiler version.
# A snapshot resolver dictates the compiler version and the set of packages
# to be used for project dependencies. For example:
#
# resolver: lts-3.5
# resolver: nightly-2015-09-21
# resolver: ghc-7.10.2
# resolver: ghcjs-0.1.0_ghc-7.10.2
# resolver:
#  name: custom-snapshot
#  location: "./custom-snapshot.yaml"
resolver: lts-7.16

# User packages to be built.
# Various formats can be used as shown in the example below.
#
# packages:
# - some-directory
# - https://example.com/foo/bar/baz-0.0.2.tar.gz
# - location:
#    git: https://github.com/commercialhaskell/stack.git
#    commit: e7b331f14bcffb8367cd58fbfc8b40ec7642100a
# - location: https://github.com/commercialhaskell/stack/commit/e7b331f14bcffb8367cd58fbfc8b40ec7642100a
#   extra-dep: true
#  subdirs:
#  - auto-update
#  - wai
#
# A package marked 'extra-dep: true' will only be built if demanded by a
# non-dependency (i.e. a user package), and its test suites and benchmarks
# will not be run. This is useful for tweaking upstream packages.
packages:
- '.'
# Dependency packages to be pulled from upstream that are not in the resolver
# (e.g., acme-missiles-0.3)
extra-deps: []


# Override default flag values for local packages and extra-deps
flags: {}

# Extra package databases containing global packages
extra-package-dbs: []

# Control whether we use the GHC we find on the path
# system-ghc: true
#
# Require a specific version of stack, using version ranges
# require-stack-version: -any # Default
# require-stack-version: ">=1.3"
#
# Override the architecture used by stack, especially useful on Windows
# arch: i386
# arch: x86_64
#
# Extra directories used by stack for building
# extra-include-dirs: [/path/to/dir]
# extra-lib-dirs: [/path/to/dir]
#
# Allow a newer minor version of GHC than the snapshot specifies
# compiler-check: newer-minor

udp-sample.cabal

name:                udp-sample
version:             0.1.0.0
synopsis:            upd sample server/client by haskell
description:         Please see README.md
homepage:            https://github.com/keizo042/upd-sample#readme
license:             BSD3
license-file:        LICENSE
author:              Kouichi Nakanishi
maintainer:          keizo.bookman@gmail.com
copyright:           2017 Kouichi Nakanishi
category:            Web
build-type:          Simple
cabal-version:       >=1.10
extra-source-files:  DESCRIPTION.md

executable server
  main-is:             Server.hs
  default-language:    Haskell2010
  build-depends:       base >= 4.7 && < 5
                      ,network
                      ,conduit-extra
                      ,unix
                      ,bytestring

executable client
  main-is:             Client.hs
  default-language:    Haskell2010
  build-depends:       base >= 4.7 && < 5
                      ,network
                      ,conduit-extra
                      ,unix
                      ,bytestring