git-annex/Command/TransferKeys.hs
Joey Hess 8a2d1988d3 expose Control.Monad.join
I think I've been looking for that function for some time.
Ie, I remember wanting to collapse Just Nothing to Nothing.
2013-04-22 20:24:53 -04:00

143 lines
3.7 KiB
Haskell

{- git-annex command, used internally by assistant
-
- Copyright 2012, 2013 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE TypeSynonymInstances, FlexibleInstances #-}
module Command.TransferKeys where
import Common.Annex
import Command
import Annex.Content
import Logs.Location
import Logs.Transfer
import qualified Remote
import Types.Remote (AssociatedFile)
import Types.Key
import qualified Option
data TransferRequest = TransferRequest Direction Remote Key AssociatedFile
def :: [Command]
def = [withOptions options $
command "transferkeys" paramNothing seek
SectionPlumbing "transfers keys"]
options :: [Option]
options = [readFdOption, writeFdOption]
readFdOption :: Option
readFdOption = Option.field [] "readfd" paramNumber "read from this fd"
writeFdOption :: Option
writeFdOption = Option.field [] "writefd" paramNumber "write to this fd"
seek :: [CommandSeek]
seek = [withField readFdOption convertFd $ \readh ->
withField writeFdOption convertFd $ \writeh ->
withNothing $ start readh writeh]
convertFd :: Maybe String -> Annex (Maybe Handle)
convertFd Nothing = return Nothing
convertFd (Just s) = liftIO $ do
case readish s of
Nothing -> error "bad fd"
Just fd -> Just <$> fdToHandle fd
start :: Maybe Handle -> Maybe Handle -> CommandStart
start readh writeh = do
runRequests (fromMaybe stdin readh) (fromMaybe stdout writeh) runner
stop
where
runner (TransferRequest direction remote key file)
| direction == Upload =
upload (Remote.uuid remote) key file forwardRetry $ \p -> do
ok <- Remote.storeKey remote key file p
when ok $
Remote.logStatus remote key InfoPresent
return ok
| otherwise = download (Remote.uuid remote) key file forwardRetry $ \p ->
getViaTmp key $ \t -> Remote.retrieveKeyFile remote key file t p
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:u:k:f:rest) = do
case (deserialize d, deserialize u, deserialize k, deserialize f) of
(Just direction, Just uuid, Just key, Just file) -> do
mremote <- Remote.remoteFromUUID uuid
case mremote of
Nothing -> sendresult False
Just 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 -> AssociatedFile -> Handle -> IO ()
sendRequest t f h = do
hPutStr h $ intercalate fieldSep
[ serialize (transferDirection t)
, serialize (transferUUID t)
, serialize (transferKey t)
, serialize f
, "" -- adds a trailing null
]
hFlush h
readResponse :: Handle -> IO Bool
readResponse h = fromMaybe False . deserialize <$> hGetLine h
fieldSep :: String
fieldSep = "\0"
class Serialized a where
serialize :: a -> String
deserialize :: String -> Maybe a
instance Serialized Bool where
serialize True = "1"
serialize False = "0"
deserialize "1" = Just True
deserialize "0" = Just False
deserialize _ = Nothing
instance Serialized Direction where
serialize Upload = "u"
serialize Download = "d"
deserialize "u" = Just Upload
deserialize "d" = Just Download
deserialize _ = Nothing
instance Serialized AssociatedFile where
serialize (Just f) = f
serialize Nothing = ""
deserialize "" = Just Nothing
deserialize f = Just $ Just f
instance Serialized UUID where
serialize = fromUUID
deserialize = Just . toUUID
instance Serialized Key where
serialize = key2file
deserialize = file2key