git-annex/Remote/Glacier.hs
Joey Hess 8025decc7f run Preparer to get Remover and CheckPresent actions
This will allow special remotes to eg, open a http connection and reuse it,
while checking if chunks are present, or removing chunks.

S3 and WebDAV both need this to support chunks with reasonable speed.

Note that a special remote might want to cache a http connection across
multiple requests. A simple case of this is that CheckPresent is typically
called before Store or Remove. A remote using this interface can certianly
use a Preparer that eg, uses a MVar to cache a http connection.

However, it's up to the remote to then deal with things like stale or
stalled http connections when eg, doing a series of downloads from a remote
and other places. There could be long delays between calls to a remote,
which could lead to eg, http connection stalls; the machine might even
move to a new network, etc.

It might be nice to improve this interface later to allow
the simple case without needing to handle the full complex case.
One way to do it would be to have a `Transaction SpecialRemote cache`,
where SpecialRemote contains methods for Storer, Retriever, Remover, and
CheckPresent, that all expect to be passed a `cache`.
2014-08-06 14:28:36 -04:00

295 lines
8.1 KiB
Haskell

{- Amazon Glacier remotes.
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.Glacier (remote, jobList) where
import qualified Data.Map as M
import qualified Data.Text as T
import qualified Data.ByteString.Lazy as L
import Common.Annex
import Types.Remote
import Types.Key
import qualified Git
import Config
import Config.Cost
import Remote.Helper.Special
import qualified Remote.Helper.AWS as AWS
import Creds
import Utility.Metered
import qualified Annex
import Annex.UUID
import Utility.Env
type Vault = String
type Archive = FilePath
remote :: RemoteType
remote = RemoteType {
typename = "glacier",
enumerate = findSpecialRemotes "glacier",
generate = gen,
setup = glacierSetup
}
gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex (Maybe Remote)
gen r u c gc = new <$> remoteCost gc veryExpensiveRemoteCost
where
new cst = Just $ specialRemote' specialcfg c
(prepareStore this)
(prepareRetrieve this)
(simplyPrepare $ remove this)
(simplyPrepare $ checkKey this)
this
where
this = Remote {
uuid = u,
cost = cst,
name = Git.repoDescribe r,
storeKey = storeKeyDummy,
retrieveKeyFile = retreiveKeyFileDummy,
retrieveKeyFileCheap = retrieveCheap this,
removeKey = removeKeyDummy,
checkPresent = checkPresentDummy,
checkPresentCheap = False,
whereisKey = Nothing,
remoteFsck = Nothing,
repairRepo = Nothing,
config = c,
repo = r,
gitconfig = gc,
localpath = Nothing,
readonly = False,
availability = GloballyAvailable,
remotetype = remote
}
specialcfg = (specialRemoteCfg c)
-- Disabled until jobList gets support for chunks.
{ chunkConfig = NoChunks
}
glacierSetup :: Maybe UUID -> Maybe CredPair -> RemoteConfig -> Annex (RemoteConfig, UUID)
glacierSetup mu mcreds c = do
u <- maybe (liftIO genUUID) return mu
c' <- setRemoteCredPair c (AWS.creds u) mcreds
glacierSetup' (isJust mu) u c'
glacierSetup' :: Bool -> UUID -> RemoteConfig -> Annex (RemoteConfig, UUID)
glacierSetup' enabling u c = do
c' <- encryptionSetup c
let fullconfig = c' `M.union` defaults
unless enabling $
genVault fullconfig u
gitConfigSpecialRemote u fullconfig "glacier" "true"
return (fullconfig, u)
where
remotename = fromJust (M.lookup "name" c)
defvault = remotename ++ "-" ++ fromUUID u
defaults = M.fromList
[ ("datacenter", T.unpack $ AWS.defaultRegion AWS.Glacier)
, ("vault", defvault)
]
prepareStore :: Remote -> Preparer Storer
prepareStore r = checkPrepare nonEmpty (byteStorer $ store r)
nonEmpty :: Key -> Annex Bool
nonEmpty k
| keySize k == Just 0 = do
warning "Cannot store empty files in Glacier."
return False
| otherwise = return True
store :: Remote -> Key -> L.ByteString -> MeterUpdate -> Annex Bool
store r k b p = go =<< glacierEnv c u
where
c = config r
u = uuid r
params = glacierParams c
[ Param "archive"
, Param "upload"
, Param "--name", Param $ archive r k
, Param $ getVault $ config r
, Param "-"
]
go Nothing = return False
go (Just e) = do
let cmd = (proc "glacier" (toCommand params)) { env = Just e }
liftIO $ catchBoolIO $
withHandle StdinHandle createProcessSuccess cmd $ \h -> do
meteredWrite p h b
return True
prepareRetrieve :: Remote -> Preparer Retriever
prepareRetrieve = simplyPrepare . byteRetriever . retrieve
retrieve :: Remote -> Key -> (L.ByteString -> Annex Bool) -> Annex Bool
retrieve r k sink = go =<< glacierEnv c u
where
c = config r
u = uuid r
params = glacierParams c
[ Param "archive"
, Param "retrieve"
, Param "-o-"
, Param $ getVault $ config r
, Param $ archive r k
]
go Nothing = error "cannot retrieve from glacier"
go (Just e) = do
let cmd = (proc "glacier" (toCommand params)) { env = Just e }
(_, Just h, _, pid) <- liftIO $ createProcess cmd
-- Glacier cannot store empty files, so if the output is
-- empty, the content is not available yet.
ok <- ifM (liftIO $ hIsEOF h)
( return False
, sink =<< liftIO (L.hGetContents h)
)
liftIO $ hClose h
liftIO $ forceSuccessProcess cmd pid
unless ok $ do
showLongNote "Recommend you wait up to 4 hours, and then run this command again."
return ok
retrieveCheap :: Remote -> Key -> FilePath -> Annex Bool
retrieveCheap _ _ _ = return False
remove :: Remote -> Remover
remove r k = glacierAction r
[ Param "archive"
, Param "delete"
, Param $ getVault $ config r
, Param $ archive r k
]
checkKey :: Remote -> CheckPresent
checkKey r k = do
showAction $ "checking " ++ name r
go =<< glacierEnv (config r) (uuid r)
where
go Nothing = error "cannot check glacier"
go (Just e) = do
{- glacier checkpresent outputs the archive name to stdout if
- it's present. -}
s <- liftIO $ readProcessEnv "glacier" (toCommand params) (Just e)
let probablypresent = key2file k `elem` lines s
if probablypresent
then ifM (Annex.getFlag "trustglacier")
( return True, error untrusted )
else return False
params = glacierParams (config r)
[ Param "archive"
, Param "checkpresent"
, Param $ getVault $ config r
, Param "--quiet"
, Param $ archive r k
]
untrusted = unlines
[ "Glacier's inventory says it has a copy."
, "However, the inventory could be out of date, if it was recently removed."
, "(Use --trust-glacier if you're sure it's still in Glacier.)"
, ""
]
glacierAction :: Remote -> [CommandParam] -> Annex Bool
glacierAction r = runGlacier (config r) (uuid r)
runGlacier :: RemoteConfig -> UUID -> [CommandParam] -> Annex Bool
runGlacier c u params = go =<< glacierEnv c u
where
go Nothing = return False
go (Just e) = liftIO $
boolSystemEnv "glacier" (glacierParams c params) (Just e)
glacierParams :: RemoteConfig -> [CommandParam] -> [CommandParam]
glacierParams c params = datacenter:params
where
datacenter = Param $ "--region=" ++
fromMaybe (error "Missing datacenter configuration")
(M.lookup "datacenter" c)
glacierEnv :: RemoteConfig -> UUID -> Annex (Maybe [(String, String)])
glacierEnv c u = go =<< getRemoteCredPairFor "glacier" c creds
where
go Nothing = return Nothing
go (Just (user, pass)) = do
e <- liftIO getEnvironment
return $ Just $ addEntries [(uk, user), (pk, pass)] e
creds = AWS.creds u
(uk, pk) = credPairEnvironment creds
getVault :: RemoteConfig -> Vault
getVault = fromMaybe (error "Missing vault configuration")
. M.lookup "vault"
archive :: Remote -> Key -> Archive
archive r k = fileprefix ++ key2file k
where
fileprefix = M.findWithDefault "" "fileprefix" $ config r
genVault :: RemoteConfig -> UUID -> Annex ()
genVault c u = unlessM (runGlacier c u params) $
error "Failed creating glacier vault."
where
params =
[ Param "vault"
, Param "create"
, Param $ getVault c
]
{- Partitions the input list of keys into ones which have
- glacier retieval jobs that have succeeded, or failed.
-
- A complication is that `glacier job list` will display the encrypted
- keys when the remote is encrypted.
-
- Dealing with encrypted chunked keys would be tricky. However, there
- seems to be no benefit to using chunking with glacier, so chunking is
- not supported.
-}
jobList :: Remote -> [Key] -> Annex ([Key], [Key])
jobList r keys = go =<< glacierEnv (config r) (uuid r)
where
params = [ Param "job", Param "list" ]
nada = ([], [])
myvault = getVault $ config r
go Nothing = return nada
go (Just e) = do
v <- liftIO $ catchMaybeIO $
readProcessEnv "glacier" (toCommand params) (Just e)
maybe (return nada) extract v
extract s = do
let result@(succeeded, failed) =
parse nada $ (map words . lines) s
if result == nada
then return nada
else do
enckeys <- forM keys $ \k ->
maybe k (\(_, enck) -> enck k)
<$> cipherKey (config r)
let keymap = M.fromList $ zip enckeys keys
let convert = mapMaybe (`M.lookup` keymap)
return (convert succeeded, convert failed)
parse c [] = c
parse c@(succeeded, failed) ((status:_date:vault:key:[]):rest)
| vault == myvault =
case file2key key of
Nothing -> parse c rest
Just k
| "a/d" `isPrefixOf` status ->
parse (k:succeeded, failed) rest
| "a/e" `isPrefixOf` status ->
parse (succeeded, k:failed) rest
| otherwise ->
parse c rest
parse c (_:rest) = parse c rest