git-annex/Remote/Rsync.hs

222 lines
6.7 KiB
Haskell
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

{- A remote that is only accessible by rsync.
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.Rsync (remote) where
import qualified Data.ByteString.Lazy as L
import qualified Data.Map as M
import System.Posix.Process (getProcessID)
import Common.Annex
import Types.Remote
import qualified Git
import Config
import Annex.Content
import Remote.Helper.Special
import Remote.Helper.Encryptable
import Crypto
import Utility.Rsync
import Annex.Perms
type RsyncUrl = String
data RsyncOpts = RsyncOpts
{ rsyncUrl :: RsyncUrl
, rsyncOptions :: [CommandParam]
, rsyncShellEscape :: Bool
}
remote :: RemoteType
remote = RemoteType {
typename = "rsync",
enumerate = findSpecialRemotes "rsyncurl",
generate = gen,
setup = rsyncSetup
}
gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex Remote
gen r u c gc = do
cst <- remoteCost gc expensiveRemoteCost
return $ encryptableRemote c
(storeEncrypted o)
(retrieveEncrypted o)
Remote
{ uuid = u
, cost = cst
, name = Git.repoDescribe r
, storeKey = store o
, retrieveKeyFile = retrieve o
, retrieveKeyFileCheap = retrieveCheap o
, removeKey = remove o
, hasKey = checkPresent r o
, hasKeyCheap = False
, whereisKey = Nothing
, config = M.empty
, repo = r
, gitconfig = gc
, localpath = if rsyncUrlIsPath $ rsyncUrl o
then Just $ rsyncUrl o
else Nothing
, readonly = False
, remotetype = remote
}
where
o = RsyncOpts url opts escape
url = fromMaybe (error "missing rsyncurl") $ remoteAnnexRsyncUrl gc
opts = map Param $ filter safe $ remoteAnnexRsyncOptions gc
escape = M.lookup "shellescape" c /= Just "no"
safe opt
-- Don't allow user to pass --delete to rsync;
-- that could cause it to delete other keys
-- in the same hash bucket as a key it sends.
| opt == "--delete" = False
| opt == "--delete-excluded" = False
| otherwise = True
rsyncSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
rsyncSetup u c = do
-- verify configuration is sane
let url = fromMaybe (error "Specify rsyncurl=") $
M.lookup "rsyncurl" c
c' <- encryptionSetup c
-- The rsyncurl is stored in git config, not only in this remote's
-- persistant state, so it can vary between hosts.
gitConfigSpecialRemote u c' "rsyncurl" url
return c'
rsyncEscape :: RsyncOpts -> String -> String
rsyncEscape o s
| rsyncShellEscape o && rsyncUrlIsShell (rsyncUrl o) = shellEscape s
| otherwise = s
rsyncUrls :: RsyncOpts -> Key -> [String]
rsyncUrls o k = map use annexHashes
where
use h = rsyncUrl o </> h k </> rsyncEscape o (f </> f)
f = keyFile k
store :: RsyncOpts -> Key -> AssociatedFile -> MeterUpdate -> Annex Bool
store o k _f p = sendAnnex k $ rsyncSend o p k
storeEncrypted :: RsyncOpts -> (Cipher, Key) -> Key -> MeterUpdate -> Annex Bool
storeEncrypted o (cipher, enck) k p = withTmp enck $ \tmp ->
sendAnnex k $ \src -> do
liftIO $ encrypt cipher (feedFile src) $
readBytes $ L.writeFile tmp
rsyncSend o p enck tmp
retrieve :: RsyncOpts -> Key -> AssociatedFile -> FilePath -> Annex Bool
retrieve o k _ f = untilTrue (rsyncUrls o k) $ \u -> rsyncRemote o Nothing
-- use inplace when retrieving to support resuming
[ Param "--inplace"
, Param u
, Param f
]
retrieveCheap :: RsyncOpts -> Key -> FilePath -> Annex Bool
retrieveCheap o k f = ifM (preseedTmp k f) ( retrieve o k undefined f , return False )
retrieveEncrypted :: RsyncOpts -> (Cipher, Key) -> Key -> FilePath -> Annex Bool
retrieveEncrypted o (cipher, enck) _ f = withTmp enck $ \tmp -> do
ifM (retrieve o enck undefined tmp)
( liftIO $ catchBoolIO $ do
decrypt cipher (feedFile tmp) $
readBytes $ L.writeFile f
return True
, return False
)
remove :: RsyncOpts -> Key -> Annex Bool
remove o k = withRsyncScratchDir $ \tmp -> liftIO $ do
{- Send an empty directory to rysnc to make it delete. -}
let dummy = tmp </> keyFile k
createDirectoryIfMissing True dummy
rsync $ rsyncOptions o ++
map (\s -> Param $ "--include=" ++ s) includes ++
[ Param "--exclude=*" -- exclude everything else
, Params "--quiet --delete --recursive"
, partialParams
, Param $ addTrailingPathSeparator dummy
, Param $ rsyncUrl o
]
where
{- Specify include rules to match the directories where the
- content could be. Note that the parent directories have
- to also be explicitly included, due to how rsync
- traverses directories. -}
includes = concatMap use annexHashes
use h = let dir = h k in
[ parentDir dir
, dir
-- match content directory and anything in it
, dir </> keyFile k </> "***"
]
checkPresent :: Git.Repo -> RsyncOpts -> Key -> Annex (Either String Bool)
checkPresent r o k = do
showAction $ "checking " ++ Git.repoDescribe r
-- note: Does not currently differentiate between rsync failing
-- to connect, and the file not being present.
Right <$> check
where
check = untilTrue (rsyncUrls o k) $ \u ->
liftIO $ catchBoolIO $ do
withQuietOutput createProcessSuccess $
proc "rsync" $ toCommand $
rsyncOptions o ++ [Param u]
return True
{- Rsync params to enable resumes of sending files safely,
- ensure that files are only moved into place once complete
-}
partialParams :: CommandParam
partialParams = Params "--partial --partial-dir=.rsync-partial"
{- Runs an action in an empty scratch directory that can be used to build
- up trees for rsync. -}
withRsyncScratchDir :: (FilePath -> Annex Bool) -> Annex Bool
withRsyncScratchDir a = do
pid <- liftIO getProcessID
t <- fromRepo gitAnnexTmpDir
createAnnexDirectory t
let tmp = t </> "rsynctmp" </> show pid
nuke tmp
liftIO $ createDirectoryIfMissing True tmp
nuke tmp `after` a tmp
where
nuke d = liftIO $ whenM (doesDirectoryExist d) $
removeDirectoryRecursive d
rsyncRemote :: RsyncOpts -> (Maybe MeterUpdate) -> [CommandParam] -> Annex Bool
rsyncRemote o callback params = do
showOutput -- make way for progress bar
ifM (liftIO $ (maybe rsync rsyncProgress callback) ps)
( return True
, do
showLongNote "rsync failed -- run git annex again to resume file transfer"
return False
)
where
defaultParams = [Params "--progress"]
ps = rsyncOptions o ++ defaultParams ++ params
{- To send a single key is slightly tricky; need to build up a temporary
- directory structure to pass to rsync so it can create the hash
- directories. -}
rsyncSend :: RsyncOpts -> MeterUpdate -> Key -> FilePath -> Annex Bool
rsyncSend o callback k src = withRsyncScratchDir $ \tmp -> do
let dest = tmp </> Prelude.head (keyPaths k)
liftIO $ createDirectoryIfMissing True $ parentDir dest
liftIO $ createLink src dest
rsyncRemote o (Just callback)
[ Param "--recursive"
, partialParams
-- tmp/ to send contents of tmp dir
, Param $ addTrailingPathSeparator tmp
, Param $ rsyncUrl o
]