git-annex/Remote/Git.hs
Joey Hess 1db7d27a45 add back debug logging
Make Utility.Process wrap the parts of System.Process that I use,
and add debug logging to them.

Also wrote some higher-level code that allows running an action
with handles to a processes stdin or stdout (or both), and checking
its exit status, all in a single function call.

As a bonus, the debug logging now indicates whether the process
is being run to read from it, feed it data, chat with it (writing and
reading), or just call it for its side effect.
2012-07-19 00:46:52 -04:00

349 lines
11 KiB
Haskell

{- Standard git remotes.
-
- Copyright 2011-2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.Git (remote, repoAvail) where
import qualified Data.Map as M
import Control.Exception.Extensible
import Common.Annex
import Utility.CopyFile
import Utility.RsyncFile
import Remote.Helper.Ssh
import Types.Remote
import qualified Git
import qualified Git.Command
import qualified Git.Config
import qualified Git.Construct
import qualified Annex
import Logs.Presence
import Logs.Transfer
import Annex.UUID
import qualified Annex.Content
import qualified Annex.BranchState
import qualified Annex.Branch
import qualified Utility.Url as Url
import Utility.TempFile
import Config
import Init
import Types.Key
import qualified Fields
remote :: RemoteType
remote = RemoteType {
typename = "git",
enumerate = list,
generate = gen,
setup = error "not supported"
}
list :: Annex [Git.Repo]
list = do
c <- fromRepo Git.config
rs <- mapM (tweakurl c) =<< fromRepo Git.remotes
mapM configread rs
where
annexurl n = "remote." ++ n ++ ".annexurl"
tweakurl c r = do
let n = fromJust $ Git.remoteName r
case M.lookup (annexurl n) c of
Nothing -> return r
Just url -> inRepo $ \g ->
Git.Construct.remoteNamed n $
Git.Construct.fromRemoteLocation url g
{- It's assumed to be cheap to read the config of non-URL
- remotes, so this is done each time git-annex is run
- in a way that uses remotes.
- Conversely, the config of an URL remote is only read
- when there is no cached UUID value. -}
configread r = do
notignored <- repoNotIgnored r
u <- getRepoUUID r
case (repoCheap r, notignored, u) of
(_, False, _) -> return r
(True, _, _) -> tryGitConfigRead r
(False, _, NoUUID) -> tryGitConfigRead r
_ -> return r
repoCheap :: Git.Repo -> Bool
repoCheap = not . Git.repoIsUrl
gen :: Git.Repo -> UUID -> Maybe RemoteConfig -> Annex Remote
gen r u _ = new <$> remoteCost r defcst
where
defcst = if repoCheap r then cheapRemoteCost else expensiveRemoteCost
new cst = Remote {
uuid = u,
cost = cst,
name = Git.repoDescribe r,
storeKey = copyToRemote r,
retrieveKeyFile = copyFromRemote r,
retrieveKeyFileCheap = copyFromRemoteCheap r,
removeKey = dropKey r,
hasKey = inAnnex r,
hasKeyCheap = repoCheap r,
whereisKey = Nothing,
config = Nothing,
repo = r,
remotetype = remote
}
{- Checks relatively inexpensively if a repository is available for use. -}
repoAvail :: Git.Repo -> Annex Bool
repoAvail r
| Git.repoIsHttp r = return True
| Git.repoIsUrl r = return True
| Git.repoIsLocalUnknown r = return False
| otherwise = liftIO $ catchBoolIO $ onLocal r $ return True
{- Avoids performing an action on a local repository that's not usable.
- Does not check that the repository is still available on disk. -}
guardUsable :: Git.Repo -> a -> Annex a -> Annex a
guardUsable r onerr a
| Git.repoIsLocalUnknown r = return onerr
| otherwise = a
{- Tries to read the config for a specified remote, updates state, and
- returns the updated repo. -}
tryGitConfigRead :: Git.Repo -> Annex Git.Repo
tryGitConfigRead r
| not $ M.null $ Git.config r = return r -- already read
| Git.repoIsSsh r = store $ onRemote r (pipedconfig, r) "configlist" [] []
| Git.repoIsHttp r = do
headers <- getHttpHeaders
store $ safely $ geturlconfig headers
| Git.repoIsUrl r = return r
| otherwise = store $ safely $ onLocal r $ do
ensureInitialized
Annex.getState Annex.repo
where
-- Reading config can fail due to IO error or
-- for other reasons; catch all possible exceptions.
safely a = either (const $ return r) return
=<< liftIO (try a :: IO (Either SomeException Git.Repo))
pipedconfig cmd params = safely $
withHandle StdoutHandle createProcessSuccess p $
Git.Config.hRead r
where
p = proc cmd $ toCommand params
geturlconfig headers = do
s <- Url.get (Git.repoLocation r ++ "/config") headers
withTempFile "git-annex.tmp" $ \tmpfile h -> do
hPutStr h s
hClose h
pipedconfig "git" [Param "config", Param "--null", Param "--list", Param "--file", File tmpfile]
store = observe $ \r' -> do
g <- gitRepo
let l = Git.remotes g
let g' = g { Git.remotes = exchange l r' }
Annex.changeState $ \s -> s { Annex.repo = g' }
exchange [] _ = []
exchange (old:ls) new
| Git.remoteName old == Git.remoteName new =
new : exchange ls new
| otherwise =
old : exchange ls new
{- Checks if a given remote has the content for a key inAnnex.
- If the remote cannot be accessed, or if it cannot determine
- whether it has the content, returns a Left error message.
-}
inAnnex :: Git.Repo -> Key -> Annex (Either String Bool)
inAnnex r key
| Git.repoIsHttp r = checkhttp =<< getHttpHeaders
| Git.repoIsUrl r = checkremote
| otherwise = checklocal
where
checkhttp headers = liftIO $ go undefined $ keyUrls r key
where
go e [] = return $ Left e
go _ (u:us) = do
res <- catchMsgIO $
Url.check u headers (keySize key)
case res of
Left e -> go e us
v -> return v
checkremote = do
showAction $ "checking " ++ Git.repoDescribe r
onRemote r (check, unknown) "inannex" [Param (show key)] []
where
check c p = dispatch <$> safeSystem c p
dispatch ExitSuccess = Right True
dispatch (ExitFailure 1) = Right False
dispatch _ = unknown
checklocal = guardUsable r unknown $ dispatch <$> check
where
check = liftIO $ catchMsgIO $ onLocal r $
Annex.Content.inAnnexSafe key
dispatch (Left e) = Left e
dispatch (Right (Just b)) = Right b
dispatch (Right Nothing) = unknown
unknown = Left $ "unable to check " ++ Git.repoDescribe r
{- Runs an action on a local repository inexpensively, by making an annex
- monad using that repository. -}
onLocal :: Git.Repo -> Annex a -> IO a
onLocal r a = do
s <- Annex.new r
Annex.eval s $ do
-- No need to update the branch; its data is not used
-- for anything onLocal is used to do.
Annex.BranchState.disableUpdate
liftIO Git.Command.reap `after` a
keyUrls :: Git.Repo -> Key -> [String]
keyUrls r key = map tourl (annexLocations key)
where
tourl l = Git.repoLocation r ++ "/" ++ l
dropKey :: Git.Repo -> Key -> Annex Bool
dropKey r key
| not $ Git.repoIsUrl r =
guardUsable r False $ commitOnCleanup r $ liftIO $ onLocal r $ do
ensureInitialized
whenM (Annex.Content.inAnnex key) $ do
Annex.Content.lockContent key $
Annex.Content.removeAnnex key
Annex.Content.logStatus key InfoMissing
Annex.Content.saveState True
return True
| Git.repoIsHttp r = error "dropping from http repo not supported"
| otherwise = commitOnCleanup r $ onRemote r (boolSystem, False) "dropkey"
[ Params "--quiet --force"
, Param $ show key
]
[]
{- Tries to copy a key's content from a remote's annex to a file. -}
copyFromRemote :: Git.Repo -> Key -> AssociatedFile -> FilePath -> Annex Bool
copyFromRemote r key file dest
| not $ Git.repoIsUrl r = guardUsable r False $ do
params <- rsyncParams r
u <- getUUID
-- run copy from perspective of remote
liftIO $ onLocal r $ do
ensureInitialized
loc <- inRepo $ gitAnnexLocation key
upload u key file $
rsyncOrCopyFile params loc dest
| Git.repoIsSsh r = rsyncHelper =<< rsyncParamsRemote r True key dest file
| Git.repoIsHttp r = Annex.Content.downloadUrl (keyUrls r key) dest
| otherwise = error "copying from non-ssh, non-http repo not supported"
copyFromRemoteCheap :: Git.Repo -> Key -> FilePath -> Annex Bool
copyFromRemoteCheap r key file
| not $ Git.repoIsUrl r = guardUsable r False $ do
loc <- liftIO $ gitAnnexLocation key r
liftIO $ catchBoolIO $ createSymbolicLink loc file >> return True
| Git.repoIsSsh r =
ifM (Annex.Content.preseedTmp key file)
( copyFromRemote r key Nothing file
, return False
)
| otherwise = return False
{- Tries to copy a key's content to a remote's annex. -}
copyToRemote :: Git.Repo -> Key -> AssociatedFile -> Annex Bool
copyToRemote r key file
| not $ Git.repoIsUrl r = guardUsable r False $ commitOnCleanup r $ do
keysrc <- inRepo $ gitAnnexLocation key
params <- rsyncParams r
u <- getUUID
-- run copy from perspective of remote
liftIO $ onLocal r $ do
ensureInitialized
download u key file $
Annex.Content.saveState True `after`
Annex.Content.getViaTmp key
(rsyncOrCopyFile params keysrc)
| Git.repoIsSsh r = commitOnCleanup r $ do
keysrc <- inRepo $ gitAnnexLocation key
rsyncHelper =<< rsyncParamsRemote r False key keysrc file
| otherwise = error "copying to non-ssh repo not supported"
rsyncHelper :: [CommandParam] -> Annex Bool
rsyncHelper p = do
showOutput -- make way for progress bar
ifM (liftIO $ rsync p)
( return True
, do
showLongNote "rsync failed -- run git annex again to resume file transfer"
return False
)
{- Copys a file with rsync unless both locations are on the same
- filesystem. Then cp could be faster. -}
rsyncOrCopyFile :: [CommandParam] -> FilePath -> FilePath -> Annex Bool
rsyncOrCopyFile rsyncparams src dest =
ifM (sameDeviceIds src dest)
( liftIO $ copyFileExternal src dest
, rsyncHelper $ rsyncparams ++ [Param src, Param dest]
)
where
sameDeviceIds a b = (==) <$> (getDeviceId a) <*> (getDeviceId b)
getDeviceId f = deviceID <$> liftIO (getFileStatus $ parentDir f)
{- Generates rsync parameters that ssh to the remote and asks it
- to either receive or send the key's content. -}
rsyncParamsRemote :: Git.Repo -> Bool -> Key -> FilePath -> AssociatedFile -> Annex [CommandParam]
rsyncParamsRemote r sending key file afile = do
u <- getUUID
let fields = (Fields.remoteUUID, fromUUID u)
: maybe [] (\f -> [(Fields.associatedFile, f)]) afile
Just (shellcmd, shellparams) <- git_annex_shell r
(if sending then "sendkey" else "recvkey")
[ Param $ show key ]
fields
-- Convert the ssh command into rsync command line.
let eparam = rsyncShell (Param shellcmd:shellparams)
o <- rsyncParams r
if sending
then return $ o ++ rsyncopts eparam dummy (File file)
else return $ o ++ rsyncopts eparam (File file) dummy
where
rsyncopts ps source dest
| end ps == [dashdash] = ps ++ [source, dest]
| otherwise = ps ++ [dashdash, source, dest]
dashdash = Param "--"
-- The rsync shell parameter controls where rsync
-- goes, so the source/dest parameter can be a dummy value,
-- that just enables remote rsync mode.
-- For maximum compatability with some patched rsyncs,
-- the dummy value needs to still contain a hostname,
-- even though this hostname will never be used.
dummy = Param "dummy:"
rsyncParams :: Git.Repo -> Annex [CommandParam]
rsyncParams r = do
o <- getRemoteConfig r "rsync-options" ""
return $ options ++ map Param (words o)
where
-- --inplace to resume partial files
options = [Params "-p --progress --inplace"]
commitOnCleanup :: Git.Repo -> Annex a -> Annex a
commitOnCleanup r a = go `after` a
where
go = Annex.addCleanup (Git.repoLocation r) cleanup
cleanup
| not $ Git.repoIsUrl r = liftIO $ onLocal r $
doQuietSideAction $
Annex.Branch.commit "update"
| otherwise = void $ do
Just (shellcmd, shellparams) <-
git_annex_shell r "commit" [] []
-- Throw away stderr, since the remote may not
-- have a new enough git-annex shell to
-- support committing.
let cmd = shellcmd ++ " "
++ unwords (map shellEscape $ toCommand shellparams)
++ ">/dev/null 2>/dev/null"
liftIO $ boolSystem "sh" [Param "-c", Param cmd]