gameServer/OfficialServer/DBInteraction.hs
author unc0rr
Sun, 02 Dec 2012 01:25:11 +0400
changeset 8178 8bd087478b48
parent 7331 0e50456d652c
child 9399 1767c92eff37
permissions -rw-r--r--
Fix QSettings problems: - Reopen file in ReadOnly mode if it was open in ReadWrite mode and is being read. This is needed for stupid QSettings which opens file in ReadWrite mode just to call readAll() on it. - Implement setSize(0)

{-# LANGUAGE CPP, ScopedTypeVariables, OverloadedStrings #-}
module OfficialServer.DBInteraction
(
    startDBConnection
) where

import Prelude hiding (catch);
import Control.Concurrent
import Control.Monad
import Data.List as L
import Data.ByteString.Char8 as B
#if defined(OFFICIAL_SERVER)
import System.Process
import System.IO as SIO
import qualified Control.Exception as Exception
import qualified Data.Map as Map
import Data.Maybe
import Data.Time
import System.Log.Logger
#endif
------------------------
import CoreTypes
#if defined(OFFICIAL_SERVER)
import Utils
#endif

localAddressList :: [B.ByteString]
localAddressList = ["127.0.0.1", "0:0:0:0:0:0:0:1", "0:0:0:0:0:ffff:7f00:1"]

fakeDbConnection :: forall b. ServerInfo -> IO b
fakeDbConnection si = forever $ do
    q <- readChan $ dbQueries si
    case q of
        CheckAccount clId clUid _ clHost ->
            writeChan (coreChan si) $ ClientAccountInfo clId clUid (if clHost `L.elem` localAddressList then Admin else Guest)
        ClearCache -> return ()
        SendStats {} -> return ()

dbConnectionLoop :: ServerInfo -> IO ()

#if defined(OFFICIAL_SERVER)
flushRequests :: ServerInfo -> IO ()
flushRequests si = do
    e <- isEmptyChan $ dbQueries si
    unless e $ do
        q <- readChan $ dbQueries si
        case q of
            CheckAccount clId clUid _ clHost ->
                writeChan (coreChan si) $ ClientAccountInfo clId clUid (if clHost `L.elem` localAddressList then Admin else Guest)
            ClearCache -> return ()
            SendStats {} -> return ()
        flushRequests si

pipeDbConnectionLoop :: Chan DBQuery -> Chan CoreMessage -> Handle -> Handle -> Map.Map ByteString (UTCTime, AccountInfo) -> Int -> IO (Map.Map ByteString (UTCTime, AccountInfo), Int)
pipeDbConnectionLoop queries cChan hIn hOut accountsCache req =
    Exception.handle (\(e :: Exception.IOException) -> warningM "Database" (show e) >> return (accountsCache, req)) $
    do
    q <- readChan queries
    (updatedCache, newReq) <- case q of
        CheckAccount clId clUid clNick _ -> do
            let cacheEntry = clNick `Map.lookup` accountsCache
            currentTime <- getCurrentTime
            if (isNothing cacheEntry) || (currentTime `diffUTCTime` (fst . fromJust) cacheEntry > 10 * 60) then
                do
                    SIO.hPutStrLn hIn $ show q
                    hFlush hIn

                    (clId', clUid', accountInfo) <- SIO.hGetLine hOut >>= (maybeException . maybeRead)

                    writeChan cChan $ ClientAccountInfo clId' clUid' accountInfo

                    return $ (Map.insert clNick (currentTime, accountInfo) accountsCache, req + 1)
                `Exception.onException`
                    (unGetChan queries q)
                else
                do
                    writeChan cChan $ ClientAccountInfo clId clUid (snd $ fromJust cacheEntry)
                    return (accountsCache, req)

        ClearCache -> return (Map.empty, req)
        SendStats {} -> (
                (SIO.hPutStrLn hIn $ show q) >>
                hFlush hIn >>
                return (accountsCache, req))
                `Exception.onException`
                (unGetChan queries q)

    pipeDbConnectionLoop queries cChan hIn hOut updatedCache newReq
    where
        maybeException (Just a) = return a
        maybeException Nothing = ioError (userError "Can't read")

pipeDbConnection ::
        Map.Map ByteString (UTCTime, AccountInfo)
        -> ServerInfo
        -> Int
        -> IO ()

pipeDbConnection accountsCache si errNum = do
    (updatedCache, newErrNum) <-
        Exception.handle (\(e :: Exception.IOException) -> warningM "Database" (show e) >> return (accountsCache, errNum + 1)) $ do
            (Just hIn, Just hOut, _, _) <- createProcess (proc "./OfficialServer/extdbinterface" [])
                    {std_in = CreatePipe,
                    std_out = CreatePipe}
            hSetBuffering hIn LineBuffering
            hSetBuffering hOut LineBuffering

            B.hPutStrLn hIn $ dbHost si
            B.hPutStrLn hIn $ dbName si
            B.hPutStrLn hIn $ dbLogin si
            B.hPutStrLn hIn $ dbPassword si
            (c, r) <- pipeDbConnectionLoop (dbQueries si) (coreChan si) hIn hOut accountsCache 0
            return (c, if r > 0 then 0 else errNum + 1)

    when (newErrNum > 1) $ flushRequests si
    threadDelay (3000000)
    pipeDbConnection updatedCache si newErrNum

dbConnectionLoop si =
        if (not . B.null $ dbHost si) then
            pipeDbConnection Map.empty si 0
        else
            fakeDbConnection si
#else
dbConnectionLoop = fakeDbConnection
#endif

startDBConnection :: ServerInfo -> IO ()
startDBConnection serverInfo =
    forkIO (dbConnectionLoop serverInfo) >> return ()