git-annex/Remote/WebDAV.hs
Joey Hess b117efc19b deal with http-conduit changing a data type
Pity that the library does not provide a function to extract the status
code from the StatusCodeException, so when they had to add a new field, it
breaks every single place that does it.
2013-02-27 00:07:28 -04:00

340 lines
11 KiB
Haskell

{- WebDAV remotes.
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE ScopedTypeVariables, CPP #-}
#if defined VERSION_http_conduit
#if ! MIN_VERSION_http_conduit(1,9,0)
#define WITH_OLD_HTTP_CONDUIT
#endif
#endif
module Remote.WebDAV (remote, davCreds, setCredsEnv) where
import Network.Protocol.HTTP.DAV
import qualified Data.Map as M
import qualified Data.ByteString.UTF8 as B8
import qualified Data.ByteString.Lazy.UTF8 as L8
import qualified Data.ByteString.Lazy as L
import Network.URI (normalizePathSegments)
import qualified Control.Exception as E
import Network.HTTP.Conduit (HttpException(..))
import Network.HTTP.Types
import System.IO.Error
import Common.Annex
import Types.Remote
import qualified Git
import Config
import Remote.Helper.Special
import Remote.Helper.Encryptable
import Remote.Helper.Chunked
import Crypto
import Creds
import Meters
import Annex.Content
type DavUrl = String
type DavUser = B8.ByteString
type DavPass = B8.ByteString
remote :: RemoteType
remote = RemoteType {
typename = "webdav",
enumerate = findSpecialRemotes "webdav",
generate = gen,
setup = webdavSetup
}
gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex Remote
gen r u c gc = new <$> remoteCost gc expensiveRemoteCost
where
new cst = encryptableRemote c
(storeEncrypted this)
(retrieveEncrypted this)
this
where
this = Remote {
uuid = u,
cost = cst,
name = Git.repoDescribe r,
storeKey = store this,
retrieveKeyFile = retrieve this,
retrieveKeyFileCheap = retrieveCheap this,
removeKey = remove this,
hasKey = checkPresent this,
hasKeyCheap = False,
whereisKey = Nothing,
config = c,
repo = r,
gitconfig = gc,
localpath = Nothing,
readonly = False,
remotetype = remote
}
webdavSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
webdavSetup u c = do
let url = fromMaybe (error "Specify url=") $
M.lookup "url" c
c' <- encryptionSetup c
creds <- getCreds c' u
testDav url creds
gitConfigSpecialRemote u c' "webdav" "true"
setRemoteCredPair c' (davCreds u)
store :: Remote -> Key -> AssociatedFile -> MeterUpdate -> Annex Bool
store r k _f p = metered (Just p) k $ \meterupdate ->
davAction r False $ \(baseurl, user, pass) ->
sendAnnex k (void $ remove r k) $ \src ->
liftIO $ withMeteredFile src meterupdate $
storeHelper r k baseurl user pass
storeEncrypted :: Remote -> (Cipher, Key) -> Key -> MeterUpdate -> Annex Bool
storeEncrypted r (cipher, enck) k p = metered (Just p) k $ \meterupdate ->
davAction r False $ \(baseurl, user, pass) ->
sendAnnex k (void $ remove r enck) $ \src ->
liftIO $ encrypt cipher (streamMeteredFile src meterupdate) $
readBytes $ storeHelper r enck baseurl user pass
storeHelper :: Remote -> Key -> DavUrl -> DavUser -> DavPass -> L.ByteString -> IO Bool
storeHelper r k baseurl user pass b = catchBoolIO $ do
davMkdir tmpurl user pass
storeChunks k tmpurl keyurl chunksize storer recorder finalizer
where
tmpurl = tmpLocation baseurl k
keyurl = davLocation baseurl k
chunksize = chunkSize $ config r
storer urls = storeChunked chunksize urls storehttp b
recorder url s = storehttp url (L8.fromString s)
finalizer srcurl desturl = do
void $ catchMaybeHttp (deleteContent desturl user pass)
davMkdir (urlParent desturl) user pass
moveContent srcurl (B8.fromString desturl) user pass
storehttp url v = putContent url user pass
(contentType, v)
retrieveCheap :: Remote -> Key -> FilePath -> Annex Bool
retrieveCheap _ _ _ = return False
retrieve :: Remote -> Key -> AssociatedFile -> FilePath -> Annex Bool
retrieve r k _f d = metered Nothing k $ \meterupdate ->
davAction r False $ \(baseurl, user, pass) -> liftIO $ catchBoolIO $
withStoredFiles r k baseurl user pass onerr $ \urls -> do
meteredWriteFileChunks meterupdate d urls $ \url -> do
mb <- davGetUrlContent url user pass
case mb of
Nothing -> throwIO "download failed"
Just b -> return b
return True
where
onerr _ = return False
retrieveEncrypted :: Remote -> (Cipher, Key) -> Key -> FilePath -> Annex Bool
retrieveEncrypted r (cipher, enck) k d = metered Nothing k $ \meterupdate ->
davAction r False $ \(baseurl, user, pass) -> liftIO $ catchBoolIO $
withStoredFiles r enck baseurl user pass onerr $ \urls -> do
decrypt cipher (feeder user pass urls) $
readBytes $ meteredWriteFile meterupdate d
return True
where
onerr _ = return False
feeder _ _ [] _ = noop
feeder user pass (url:urls) h = do
mb <- davGetUrlContent url user pass
case mb of
Nothing -> throwIO "download failed"
Just b -> do
L.hPut h b
feeder user pass urls h
remove :: Remote -> Key -> Annex Bool
remove r k = davAction r False $ \(baseurl, user, pass) -> liftIO $ do
-- Delete the key's whole directory, including any chunked
-- files, etc, in a single action.
let url = davLocation baseurl k
isJust <$> catchMaybeHttp (deleteContent url user pass)
checkPresent :: Remote -> Key -> Annex (Either String Bool)
checkPresent r k = davAction r noconn go
where
noconn = Left $ error $ name r ++ " not configured"
go (baseurl, user, pass) = do
showAction $ "checking " ++ name r
liftIO $ withStoredFiles r k baseurl user pass onerr check
where
check [] = return $ Right True
check (url:urls) = do
v <- davUrlExists url user pass
if v == Right True
then check urls
else return v
{- Failed to read the chunkcount file; see if it's missing,
- or if there's a problem accessing it,
- or perhaps this was an intermittent error. -}
onerr url = do
v <- davUrlExists url user pass
if v == Right True
then return $ Left $ "failed to read " ++ url
else return v
withStoredFiles
:: Remote
-> Key
-> DavUrl
-> DavUser
-> DavPass
-> (DavUrl -> IO a)
-> ([DavUrl] -> IO a)
-> IO a
withStoredFiles r k baseurl user pass onerr a
| isJust $ chunkSize $ config r = do
let chunkcount = keyurl ++ chunkCount
maybe (onerr chunkcount) (a . listChunks keyurl . L8.toString)
=<< davGetUrlContent chunkcount user pass
| otherwise = a [keyurl]
where
keyurl = davLocation baseurl k ++ keyFile k
davAction :: Remote -> a -> ((DavUrl, DavUser, DavPass) -> Annex a) -> Annex a
davAction r unconfigured action = do
mcreds <- getCreds (config r) (uuid r)
case (mcreds, M.lookup "url" $ config r) of
(Just (user, pass), Just url) ->
action (url, toDavUser user, toDavPass pass)
_ -> return unconfigured
toDavUser :: String -> DavUser
toDavUser = B8.fromString
toDavPass :: String -> DavPass
toDavPass = B8.fromString
{- The directory where files(s) for a key are stored. -}
davLocation :: DavUrl -> Key -> DavUrl
davLocation baseurl k = addTrailingPathSeparator $
davUrl baseurl $ hashDirLower k </> keyFile k
{- Where we store temporary data for a key as it's being uploaded. -}
tmpLocation :: DavUrl -> Key -> DavUrl
tmpLocation baseurl k = addTrailingPathSeparator $
davUrl baseurl $ "tmp" </> keyFile k
davUrl :: DavUrl -> FilePath -> DavUrl
davUrl baseurl file = baseurl </> file
davUrlExists :: DavUrl -> DavUser -> DavPass -> IO (Either String Bool)
davUrlExists url user pass = decode <$> catchHttp (getProps url user pass)
where
decode (Right _) = Right True
#ifdef WITH_OLD_HTTP_CONDUIT
decode (Left (Left (StatusCodeException status _)))
#else
decode (Left (Left (StatusCodeException status _ _)))
#endif
| statusCode status == statusCode notFound404 = Right False
decode (Left e) = Left $ showEitherException e
davGetUrlContent :: DavUrl -> DavUser -> DavPass -> IO (Maybe L.ByteString)
davGetUrlContent url user pass = fmap (snd . snd) <$>
catchMaybeHttp (getPropsAndContent url user pass)
{- Creates a directory in WebDAV, if not already present; also creating
- any missing parent directories. -}
davMkdir :: DavUrl -> DavUser -> DavPass -> IO ()
davMkdir url user pass = go url
where
make u = makeCollection u user pass
go u = do
r <- E.try (make u) :: IO (Either E.SomeException Bool)
case r of
{- Parent directory is missing. Recurse to create
- it, and try once more to create the directory. -}
Right False -> do
go (urlParent u)
void $ make u
{- Directory created successfully -}
Right True -> return ()
{- Directory already exists, or some other error
- occurred. In the latter case, whatever wanted
- to use this directory will fail. -}
Left _ -> return ()
{- Catches HTTP and IO exceptions. -}
catchMaybeHttp :: IO a -> IO (Maybe a)
catchMaybeHttp a = (Just <$> a) `E.catches`
[ E.Handler $ \(_e :: HttpException) -> return Nothing
, E.Handler $ \(_e :: E.IOException) -> return Nothing
]
{- Catches HTTP and IO exceptions -}
catchHttp :: IO a -> IO (Either EitherException a)
catchHttp a = (Right <$> a) `E.catches`
[ E.Handler $ \(e :: HttpException) -> return $ Left $ Left e
, E.Handler $ \(e :: E.IOException) -> return $ Left $ Right e
]
type EitherException = Either HttpException E.IOException
showEitherException :: EitherException -> String
#ifdef WITH_OLD_HTTP_CONDUIT
showEitherException (Left (StatusCodeException status _)) =
#else
showEitherException (Left (StatusCodeException status _ _)) =
#endif
show $ statusMessage status
showEitherException (Left httpexception) = show httpexception
showEitherException (Right ioexception) = show ioexception
throwIO :: String -> IO a
throwIO msg = ioError $ mkIOError userErrorType msg Nothing Nothing
urlParent :: DavUrl -> DavUrl
urlParent url = dropTrailingPathSeparator $
normalizePathSegments (dropTrailingPathSeparator url ++ "/..")
where
{- Test if a WebDAV store is usable, by writing to a test file, and then
- deleting the file. Exits with an IO error if not. -}
testDav :: String -> Maybe CredPair -> Annex ()
testDav baseurl (Just (u, p)) = do
showSideAction "testing WebDAV server"
test "make directory" $ davMkdir baseurl user pass
test "write file" $ putContent testurl user pass
(contentType, L.empty)
test "delete file" $ deleteContent testurl user pass
where
test desc a = liftIO $
either (\e -> throwIO $ "WebDAV failed to " ++ desc ++ ": " ++ showEitherException e)
(const noop)
=<< catchHttp a
user = toDavUser u
pass = toDavPass p
testurl = davUrl baseurl "git-annex-test"
testDav _ Nothing = error "Need to configure webdav username and password."
{- Content-Type to use for files uploaded to WebDAV. -}
contentType :: Maybe B8.ByteString
contentType = Just $ B8.fromString "application/octet-stream"
getCreds :: RemoteConfig -> UUID -> Annex (Maybe CredPair)
getCreds c u = getRemoteCredPairFor "webdav" c (davCreds u)
davCreds :: UUID -> CredPairStorage
davCreds u = CredPairStorage
{ credPairFile = fromUUID u
, credPairEnvironment = ("WEBDAV_USERNAME", "WEBDAV_PASSWORD")
, credPairRemoteKey = Just "davcreds"
}
setCredsEnv :: (String, String) -> IO ()
setCredsEnv creds = setEnvCredPair creds $ davCreds undefined