git-annex/Assistant/XMPP/Client.hs
2012-11-02 14:28:36 -04:00

84 lines
2.3 KiB
Haskell

{- xmpp client support
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Assistant.XMPP.Client where
import Assistant.Common
import Utility.FileMode
import Utility.SRV
import Network.Protocol.XMPP
import Network
import Control.Concurrent
import qualified Data.Text as T
import Control.Exception (SomeException)
{- Everything we need to know to connect to an XMPP server. -}
data XMPPCreds = XMPPCreds
{ xmppUsername :: T.Text
, xmppPassword :: T.Text
, xmppHostname :: HostName
, xmppPort :: Int
, xmppJID :: T.Text
}
deriving (Read, Show)
connectXMPP :: XMPPCreds -> (JID -> XMPP a) -> IO (Either SomeException ())
connectXMPP c a = case parseJID (xmppJID c) of
Nothing -> error "bad JID"
Just jid -> connectXMPP' jid c a
{- Do a SRV lookup, but if it fails, fall back to the cached xmppHostname. -}
connectXMPP' :: JID -> XMPPCreds -> (JID -> XMPP a) -> IO (Either SomeException ())
connectXMPP' jid c a = go =<< lookupSRV srvrecord
where
srvrecord = mkSRVTcp "xmpp-client" $
T.unpack $ strDomain $ jidDomain jid
serverjid = JID Nothing (jidDomain jid) Nothing
go [] = run (xmppHostname c)
(PortNumber $ fromIntegral $ xmppPort c)
(a jid)
go ((h,p):rest) = do
{- Try each SRV record in turn, until one connects,
- at which point the MVar will be full. -}
mv <- newEmptyMVar
r <- run h p $ do
liftIO $ putMVar mv ()
a jid
ifM (isEmptyMVar mv) (go rest, return r)
{- Async exceptions are let through so the XMPP thread can
- be killed. -}
run h p a' = tryNonAsync $
runClientError (Server serverjid h p) jid
(xmppUsername c) (xmppPassword c) (void a')
{- XMPP runClient, that throws errors rather than returning an Either -}
runClientError :: Server -> JID -> T.Text -> T.Text -> XMPP a -> IO a
runClientError s j u p x = either (error . show) return =<< runClient s j u p x
getXMPPCreds :: Annex (Maybe XMPPCreds)
getXMPPCreds = do
f <- xmppCredsFile
s <- liftIO $ catchMaybeIO $ readFile f
return $ readish =<< s
setXMPPCreds :: XMPPCreds -> Annex ()
setXMPPCreds creds = do
f <- xmppCredsFile
liftIO $ do
h <- openFile f WriteMode
modifyFileMode f $ removeModes
[groupReadMode, otherReadMode]
hPutStr h (show creds)
hClose h
xmppCredsFile :: Annex FilePath
xmppCredsFile = do
dir <- fromRepo gitAnnexCredsDir
return $ dir </> "notify-xmpp"