git-annex/Command/TransferKeys.hs
Joey Hess 5f0b551c0c
assistant: Fix race in v6 mode that caused downloaded file content to sometimes not replace pointer files.
The keys database handle needs to be closed after merging, because the
smudge filter, in another process, updates the database. Old cached info
can be read for a while from the open database handle; closing it ensures
that the info written by the smudge filter is available.

This is pretty horribly ad-hoc, and it's especially nasty that the
transferrer closes the database every time.
2016-05-16 14:49:12 -04:00

136 lines
3.6 KiB
Haskell

{- git-annex command, used internally by assistant
-
- Copyright 2012, 2013 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE TypeSynonymInstances, FlexibleInstances #-}
module Command.TransferKeys where
import Command
import Annex.Content
import Logs.Location
import Annex.Transfer
import qualified Remote
import Utility.SimpleProtocol (dupIoHandles)
import Git.Types (RemoteName)
import qualified Database.Keys
data TransferRequest = TransferRequest Direction Remote Key AssociatedFile
cmd :: Command
cmd = command "transferkeys" SectionPlumbing "transfers keys"
paramNothing (withParams seek)
seek :: CmdParams -> CommandSeek
seek = withNothing start
start :: CommandStart
start = do
(readh, writeh) <- liftIO dupIoHandles
runRequests readh writeh runner
stop
where
runner (TransferRequest direction remote key file)
| direction == Upload = notifyTransfer direction file $
upload (Remote.uuid remote) key file forwardRetry observer $ \p -> do
ok <- Remote.storeKey remote key file p
when ok $
Remote.logStatus remote key InfoPresent
return ok
| otherwise = notifyTransfer direction file $
download (Remote.uuid remote) key file forwardRetry observer $ \p ->
getViaTmp (RemoteVerify remote) key $ \t -> do
r <- Remote.retrieveKeyFile remote key file t p
-- Make sure we get the current
-- associated files data for the key,
-- not old cached data.
Database.Keys.closeDb
return r
observer False t tinfo = recordFailedTransfer t tinfo
observer True _ _ = noop
runRequests
:: Handle
-> Handle
-> (TransferRequest -> Annex Bool)
-> Annex ()
runRequests readh writeh a = do
liftIO $ do
hSetBuffering readh NoBuffering
fileEncoding readh
fileEncoding writeh
go =<< readrequests
where
go (d:rn:k:f:rest) = do
case (deserialize d, deserialize rn, deserialize k, deserialize f) of
(Just direction, Just remotename, Just key, Just file) -> do
mremote <- Remote.byName' remotename
case mremote of
Left _ -> sendresult False
Right remote -> sendresult =<< a
(TransferRequest direction remote key file)
_ -> sendresult False
go rest
go [] = noop
go [""] = noop
go v = error $ "transferkeys protocol error: " ++ show v
readrequests = liftIO $ split fieldSep <$> hGetContents readh
sendresult b = liftIO $ do
hPutStrLn writeh $ serialize b
hFlush writeh
sendRequest :: Transfer -> TransferInfo -> Handle -> IO ()
sendRequest t tinfo h = do
hPutStr h $ intercalate fieldSep
[ serialize (transferDirection t)
, maybe (serialize (fromUUID (transferUUID t)))
(serialize . Remote.name)
(transferRemote tinfo)
, serialize (transferKey t)
, serialize (associatedFile tinfo)
, "" -- adds a trailing null
]
hFlush h
readResponse :: Handle -> IO Bool
readResponse h = fromMaybe False . deserialize <$> hGetLine h
fieldSep :: String
fieldSep = "\0"
class TCSerialized a where
serialize :: a -> String
deserialize :: String -> Maybe a
instance TCSerialized Bool where
serialize True = "1"
serialize False = "0"
deserialize "1" = Just True
deserialize "0" = Just False
deserialize _ = Nothing
instance TCSerialized Direction where
serialize Upload = "u"
serialize Download = "d"
deserialize "u" = Just Upload
deserialize "d" = Just Download
deserialize _ = Nothing
instance TCSerialized AssociatedFile where
serialize (Just f) = f
serialize Nothing = ""
deserialize "" = Just Nothing
deserialize f = Just $ Just f
instance TCSerialized RemoteName where
serialize n = n
deserialize n = Just n
instance TCSerialized Key where
serialize = key2file
deserialize = file2key