git-annex/Remote/S3.hs
Joey Hess 5fe49b98f8 Support hot-swapping of removable drives containing gcrypt repositories.
To support this, a core.gcrypt-id is stored by git-annex inside the git
config of a local gcrypt repository, when setting it up.

That is compared with the remote's cached gcrypt-id. When different, a
drive has been changed. git-annex then looks up the remote config for
the uuid mapped from the core.gcrypt-id, and tweaks the configuration
appropriately. When there is no known config for the uuid, it will refuse to
use the remote.
2013-09-12 15:54:35 -04:00

342 lines
11 KiB
Haskell

{- S3 remotes
-
- Copyright 2011-2013 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.S3 (remote, iaHost, isIA, isIAHost, iaItemUrl) where
import Network.AWS.AWSConnection
import Network.AWS.S3Object hiding (getStorageClass)
import Network.AWS.S3Bucket hiding (size)
import Network.AWS.AWSResult
import qualified Data.Text as T
import qualified Data.ByteString.Lazy.Char8 as L
import qualified Data.Map as M
import Data.Char
import Network.Socket (HostName)
import Common.Annex
import Types.Remote
import Types.Key
import qualified Git
import Config
import Config.Cost
import Remote.Helper.Special
import Remote.Helper.Encryptable
import qualified Remote.Helper.AWS as AWS
import Crypto
import Creds
import Utility.Metered
import Annex.Content
import Annex.UUID
import Logs.Web
type Bucket = String
remote :: RemoteType
remote = RemoteType {
typename = "S3",
enumerate = findSpecialRemotes "s3",
generate = gen,
setup = s3Setup
}
gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex (Maybe Remote)
gen r u c gc = new <$> remoteCost gc expensiveRemoteCost
where
new cst = Just $ 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 c,
hasKey = checkPresent this,
hasKeyCheap = False,
whereisKey = Nothing,
config = c,
repo = r,
gitconfig = gc,
localpath = Nothing,
readonly = False,
globallyAvailable = True,
remotetype = remote
}
s3Setup :: Maybe UUID -> RemoteConfig -> Annex (RemoteConfig, UUID)
s3Setup mu c = do
u <- maybe (liftIO genUUID) return mu
s3Setup' u c
s3Setup' :: UUID -> RemoteConfig -> Annex (RemoteConfig, UUID)
s3Setup' u c = if isIA c then archiveorg else defaulthost
where
remotename = fromJust (M.lookup "name" c)
defbucket = remotename ++ "-" ++ fromUUID u
defaults = M.fromList
[ ("datacenter", T.unpack $ AWS.defaultRegion AWS.S3)
, ("storageclass", "STANDARD")
, ("host", defaultAmazonS3Host)
, ("port", show defaultAmazonS3Port)
, ("bucket", defbucket)
]
use fullconfig = do
gitConfigSpecialRemote u fullconfig "s3" "true"
c' <- setRemoteCredPair fullconfig (AWS.creds u)
return (c', u)
defaulthost = do
c' <- encryptionSetup c
let fullconfig = c' `M.union` defaults
genBucket fullconfig u
use fullconfig
archiveorg = do
showNote "Internet Archive mode"
maybe (error "specify bucket=") (const noop) $
getBucket archiveconfig
writeUUIDFile archiveconfig u
use archiveconfig
where
archiveconfig =
-- hS3 does not pass through x-archive-* headers
M.mapKeys (replace "x-archive-" "x-amz-") $
-- encryption does not make sense here
M.insert "encryption" "none" $
M.union c $
-- special constraints on key names
M.insert "mungekeys" "ia" $
-- bucket created only when files are uploaded
M.insert "x-amz-auto-make-bucket" "1" $
-- no default bucket name; should be human-readable
M.delete "bucket" defaults
store :: Remote -> Key -> AssociatedFile -> MeterUpdate -> Annex Bool
store r k _f p = s3Action r False $ \(conn, bucket) ->
sendAnnex k (void $ remove' r k) $ \src -> do
ok <- s3Bool =<< storeHelper (conn, bucket) r k p src
-- Store public URL to item in Internet Archive.
when (ok && isIA (config r)) $
setUrlPresent k (iaKeyUrl r k)
return ok
storeEncrypted :: Remote -> (Cipher, Key) -> Key -> MeterUpdate -> Annex Bool
storeEncrypted r (cipher, enck) k p = s3Action r False $ \(conn, bucket) ->
-- To get file size of the encrypted content, have to use a temp file.
-- (An alternative would be chunking to to a constant size.)
withTmp enck $ \tmp -> sendAnnex k (void $ remove' r enck) $ \src -> do
liftIO $ encrypt (getGpgEncParams r) cipher (feedFile src) $
readBytes $ L.writeFile tmp
s3Bool =<< storeHelper (conn, bucket) r enck p tmp
storeHelper :: (AWSConnection, Bucket) -> Remote -> Key -> MeterUpdate -> FilePath -> Annex (AWSResult ())
storeHelper (conn, bucket) r k p file = do
size <- maybe getsize (return . fromIntegral) $ keySize k
meteredBytes (Just p) size $ \meterupdate ->
liftIO $ withMeteredFile file meterupdate $ \content -> do
-- size is provided to S3 so the whole content
-- does not need to be buffered to calculate it
let object = S3Object
bucket (bucketFile r k) ""
(("Content-Length", show size) : getXheaders (config r))
content
sendObject conn $
setStorageClass (getStorageClass $ config r) object
where
getsize = liftIO $ fromIntegral . fileSize <$> getFileStatus file
retrieve :: Remote -> Key -> AssociatedFile -> FilePath -> MeterUpdate -> Annex Bool
retrieve r k _f d p = s3Action r False $ \(conn, bucket) ->
metered (Just p) k $ \meterupdate -> do
res <- liftIO $ getObject conn $ bucketKey r bucket k
case res of
Right o -> do
liftIO $ meteredWriteFile meterupdate d $
obj_data o
return True
Left e -> s3Warning e
retrieveCheap :: Remote -> Key -> FilePath -> Annex Bool
retrieveCheap _ _ _ = return False
retrieveEncrypted :: Remote -> (Cipher, Key) -> Key -> FilePath -> MeterUpdate -> Annex Bool
retrieveEncrypted r (cipher, enck) k d p = s3Action r False $ \(conn, bucket) ->
metered (Just p) k $ \meterupdate -> do
res <- liftIO $ getObject conn $ bucketKey r bucket enck
case res of
Right o -> liftIO $ decrypt cipher (\h -> meteredWrite meterupdate h $ obj_data o) $
readBytes $ \content -> do
L.writeFile d content
return True
Left e -> s3Warning e
{- Internet Archive doesn't easily allow removing content.
- While it may remove the file, there are generally other files
- derived from it that it does not remove. -}
remove :: Remote -> RemoteConfig -> Key -> Annex Bool
remove r c k
| isIA c = do
warning "Cannot remove content from the Internet Archive"
return False
| otherwise = remove' r k
remove' :: Remote -> Key -> Annex Bool
remove' r k = s3Action r False $ \(conn, bucket) ->
s3Bool =<< liftIO (deleteObject conn $ bucketKey r bucket k)
checkPresent :: Remote -> Key -> Annex (Either String Bool)
checkPresent r k = s3Action r noconn $ \(conn, bucket) -> do
showAction $ "checking " ++ name r
res <- liftIO $ getObjectInfo conn $ bucketKey r bucket k
case res of
Right _ -> return $ Right True
Left (AWSError _ _) -> return $ Right False
Left e -> return $ Left (s3Error e)
where
noconn = Left $ error "S3 not configured"
s3Warning :: ReqError -> Annex Bool
s3Warning e = do
warning $ prettyReqError e
return False
s3Error :: ReqError -> a
s3Error e = error $ prettyReqError e
s3Bool :: AWSResult () -> Annex Bool
s3Bool (Right _) = return True
s3Bool (Left e) = s3Warning e
s3Action :: Remote -> a -> ((AWSConnection, Bucket) -> Annex a) -> Annex a
s3Action r noconn action = do
let bucket = M.lookup "bucket" $ config r
conn <- s3Connection (config r) (uuid r)
case (bucket, conn) of
(Just b, Just c) -> action (c, b)
_ -> return noconn
bucketFile :: Remote -> Key -> FilePath
bucketFile r = munge . key2file
where
munge s = case M.lookup "mungekeys" c of
Just "ia" -> iaMunge $ filePrefix c ++ s
_ -> filePrefix c ++ s
c = config r
filePrefix :: RemoteConfig -> String
filePrefix = M.findWithDefault "" "fileprefix"
bucketKey :: Remote -> Bucket -> Key -> S3Object
bucketKey r bucket k = S3Object bucket (bucketFile r k) "" [] L.empty
{- Internet Archive limits filenames to a subset of ascii,
- with no whitespace. Other characters are xml entity
- encoded. -}
iaMunge :: String -> String
iaMunge = (>>= munge)
where
munge c
| isAsciiUpper c || isAsciiLower c || isNumber c = [c]
| c `elem` "_-.\"" = [c]
| isSpace c = []
| otherwise = "&" ++ show (ord c) ++ ";"
genBucket :: RemoteConfig -> UUID -> Annex ()
genBucket c u = do
conn <- s3ConnectionRequired c u
showAction "checking bucket"
loc <- liftIO $ getBucketLocation conn bucket
case loc of
Right _ -> writeUUIDFile c u
Left err@(NetworkError _) -> s3Error err
Left (AWSError _ _) -> do
showAction $ "creating bucket in " ++ datacenter
res <- liftIO $ createBucketIn conn bucket datacenter
case res of
Right _ -> writeUUIDFile c u
Left err -> s3Error err
where
bucket = fromJust $ getBucket c
datacenter = fromJust $ M.lookup "datacenter" c
{- Writes the UUID to an annex-uuid file within the bucket.
-
- If the file already exists in the bucket, it must match.
-
- Note that IA items do not get created by createBucketIn.
- Rather, they are created the first time a file is stored in them.
- So this also takes care of that.
-}
writeUUIDFile :: RemoteConfig -> UUID -> Annex ()
writeUUIDFile c u = do
conn <- s3ConnectionRequired c u
go conn =<< liftIO (tryNonAsync $ getObject conn $ mkobject L.empty)
where
go _conn (Right (Right o)) = unless (obj_data o == uuidb) $
error $ "This bucket is already in use by a different S3 special remote, with UUID: " ++ L.unpack (obj_data o)
go conn _ = do
let object = setStorageClass (getStorageClass c) (mkobject uuidb)
either s3Error return =<< liftIO (sendObject conn object)
file = filePrefix c ++ "annex-uuid"
uuidb = L.pack $ fromUUID u
bucket = fromJust $ getBucket c
mkobject = S3Object bucket file "" (getXheaders c)
s3ConnectionRequired :: RemoteConfig -> UUID -> Annex AWSConnection
s3ConnectionRequired c u =
maybe (error "Cannot connect to S3") return =<< s3Connection c u
s3Connection :: RemoteConfig -> UUID -> Annex (Maybe AWSConnection)
s3Connection c u = go =<< getRemoteCredPairFor "S3" c (AWS.creds u)
where
go Nothing = return Nothing
go (Just (ak, sk)) = return $ Just $ AWSConnection host port ak sk
host = fromJust $ M.lookup "host" c
port = let s = fromJust $ M.lookup "port" c in
case reads s of
[(p, _)] -> p
_ -> error $ "bad S3 port value: " ++ s
getBucket :: RemoteConfig -> Maybe Bucket
getBucket = M.lookup "bucket"
getStorageClass :: RemoteConfig -> StorageClass
getStorageClass c = case fromJust $ M.lookup "storageclass" c of
"REDUCED_REDUNDANCY" -> REDUCED_REDUNDANCY
_ -> STANDARD
getXheaders :: RemoteConfig -> [(String, String)]
getXheaders = filter isxheader . M.assocs
where
isxheader (h, _) = "x-amz-" `isPrefixOf` h
{- Hostname to use for archive.org S3. -}
iaHost :: HostName
iaHost = "s3.us.archive.org"
isIA :: RemoteConfig -> Bool
isIA c = maybe False isIAHost (M.lookup "host" c)
isIAHost :: HostName -> Bool
isIAHost h = ".archive.org" `isSuffixOf` map toLower h
iaItemUrl :: Bucket -> URLString
iaItemUrl bucket = "http://archive.org/details/" ++ bucket
iaKeyUrl :: Remote -> Key -> URLString
iaKeyUrl r k = "http://archive.org/download/" ++ bucket ++ "/" ++ bucketFile r k
where
bucket = fromMaybe "" $ getBucket $ config r