git-annex/Remote/S3real.hs
2011-10-16 00:50:12 -04:00

311 lines
9.2 KiB
Haskell

{- Amazon S3 remotes.
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.S3 (remote) where
import Network.AWS.AWSConnection
import Network.AWS.S3Object
import Network.AWS.S3Bucket hiding (size)
import Network.AWS.AWSResult
import qualified Data.ByteString.Lazy.Char8 as L
import qualified Data.Map as M
import Data.Char
import System.Environment
import System.Posix.Env (setEnv)
import Common.Annex
import Types.Remote
import Types.Key
import qualified Git
import Config
import Remote.Helper.Special
import Remote.Helper.Encryptable
import Crypto
import Annex.Content
import Utility.Base64
remote :: RemoteType Annex
remote = RemoteType {
typename = "S3",
enumerate = findSpecialRemotes "s3",
generate = gen,
setup = s3Setup
}
gen :: Git.Repo -> UUID -> Maybe RemoteConfig -> Annex (Remote Annex)
gen r u c = do
cst <- remoteCost r expensiveRemoteCost
return $ gen' r u c cst
gen' :: Git.Repo -> UUID -> Maybe RemoteConfig -> Int -> Remote Annex
gen' r u c 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,
removeKey = remove this,
hasKey = checkPresent this,
hasKeyCheap = False,
config = c,
repo = r
}
s3Setup :: UUID -> RemoteConfig -> Annex RemoteConfig
s3Setup u c = handlehost $ M.lookup "host" c
where
remotename = fromJust (M.lookup "name" c)
defbucket = remotename ++ "-" ++ u
defaults = M.fromList
[ ("datacenter", "US")
, ("storageclass", "STANDARD")
, ("host", defaultAmazonS3Host)
, ("port", show defaultAmazonS3Port)
, ("bucket", defbucket)
]
handlehost Nothing = defaulthost
handlehost (Just h)
| ".archive.org" `isSuffixOf` map toLower h = archiveorg
| otherwise = defaulthost
use fullconfig = do
gitConfigSpecialRemote u fullconfig "s3" "true"
s3SetCreds fullconfig
defaulthost = do
c' <- encryptionSetup c
let fullconfig = c' `M.union` defaults
genBucket fullconfig
use fullconfig
archiveorg = do
showNote "Internet Archive mode"
maybe (error "specify bucket=") (const $ return ()) $
M.lookup "bucket" archiveconfig
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 Annex -> Key -> Annex Bool
store r k = s3Action r False $ \(conn, bucket) -> do
g <- gitRepo
res <- liftIO $ storeHelper (conn, bucket) r k $ gitAnnexLocation g k
s3Bool res
storeEncrypted :: Remote Annex -> (Cipher, Key) -> Key -> Annex Bool
storeEncrypted r (cipher, enck) k = 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 -> do
g <- gitRepo
let f = gitAnnexLocation g k
liftIO $ withEncryptedContent cipher (L.readFile f) $ \s -> L.writeFile tmp s
res <- liftIO $ storeHelper (conn, bucket) r enck tmp
s3Bool res
storeHelper :: (AWSConnection, String) -> Remote Annex -> Key -> FilePath -> IO (AWSResult ())
storeHelper (conn, bucket) r k file = do
content <- liftIO $ L.readFile file
-- size is provided to S3 so the whole content does not need to be
-- buffered to calculate it
size <- maybe getsize (return . fromIntegral) $ keySize k
let object = setStorageClass storageclass $
S3Object bucket (bucketFile r k) ""
(("Content-Length", show size) : xheaders) content
sendObject conn object
where
storageclass =
case fromJust $ M.lookup "storageclass" $ fromJust $ config r of
"REDUCED_REDUNDANCY" -> REDUCED_REDUNDANCY
_ -> STANDARD
getsize = do
s <- liftIO $ getFileStatus file
return $ fileSize s
xheaders = filter isxheader $ M.assocs $ fromJust $ config r
isxheader (h, _) = "x-amz-" `isPrefixOf` h
retrieve :: Remote Annex -> Key -> FilePath -> Annex Bool
retrieve r k f = s3Action r False $ \(conn, bucket) -> do
res <- liftIO $ getObject conn $ bucketKey r bucket k
case res of
Right o -> do
liftIO $ L.writeFile f $ obj_data o
return True
Left e -> s3Warning e
retrieveEncrypted :: Remote Annex -> (Cipher, Key) -> FilePath -> Annex Bool
retrieveEncrypted r (cipher, enck) f = s3Action r False $ \(conn, bucket) -> do
res <- liftIO $ getObject conn $ bucketKey r bucket enck
case res of
Right o -> liftIO $
withDecryptedContent cipher (return $ obj_data o) $ \content -> do
L.writeFile f content
return True
Left e -> s3Warning e
remove :: Remote Annex -> Key -> Annex Bool
remove r k = s3Action r False $ \(conn, bucket) -> do
res <- liftIO $ deleteObject conn $ bucketKey r bucket k
s3Bool res
checkPresent :: Remote Annex -> Key -> Annex (Either IOException 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 Annex -> a -> ((AWSConnection, String) -> Annex a) -> Annex a
s3Action r noconn action = do
when (isNothing $ config r) $
error $ "Missing configuration for special remote " ++ name r
let bucket = M.lookup "bucket" $ fromJust $ config r
conn <- s3Connection $ fromJust $ config r
case (bucket, conn) of
(Just b, Just c) -> action (c, b)
_ -> return noconn
bucketFile :: Remote Annex -> Key -> FilePath
bucketFile r = munge . show
where
munge s = case M.lookup "mungekeys" $ fromJust $ config r of
Just "ia" -> iaMunge s
_ -> s
bucketKey :: Remote Annex -> String -> 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 -> Annex ()
genBucket c = do
conn <- s3ConnectionRequired c
showAction "checking bucket"
loc <- liftIO $ getBucketLocation conn bucket
case loc of
Right _ -> return ()
Left err@(NetworkError _) -> s3Error err
Left (AWSError _ _) -> do
showAction $ "creating bucket in " ++ datacenter
res <- liftIO $ createBucketIn conn bucket datacenter
case res of
Right _ -> return ()
Left err -> s3Error err
where
bucket = fromJust $ M.lookup "bucket" c
datacenter = fromJust $ M.lookup "datacenter" c
s3ConnectionRequired :: RemoteConfig -> Annex AWSConnection
s3ConnectionRequired c =
maybe (error "Cannot connect to S3") return =<< s3Connection c
s3Connection :: RemoteConfig -> Annex (Maybe AWSConnection)
s3Connection c = do
creds <- s3GetCreds c
case creds of
Just (ak, sk) -> return $ Just $ AWSConnection host port ak sk
_ -> do
warning $ "Set both " ++ s3AccessKey ++ " and " ++ s3SecretKey ++ " to use S3"
return Nothing
where
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
{- S3 creds come from the environment if set.
- Otherwise, might be stored encrypted in the remote's config. -}
s3GetCreds :: RemoteConfig -> Annex (Maybe (String, String))
s3GetCreds c = do
ak <- getEnvKey s3AccessKey
sk <- getEnvKey s3SecretKey
if null ak || null sk
then do
mcipher <- remoteCipher c
case (M.lookup "s3creds" c, mcipher) of
(Just encrypted, Just cipher) -> do
s <- liftIO $ withDecryptedContent cipher
(return $ L.pack $ fromB64 encrypted)
(return . L.unpack)
let [ak', sk', _rest] = lines s
liftIO $ do
setEnv s3AccessKey ak True
setEnv s3SecretKey sk True
return $ Just (ak', sk')
_ -> return Nothing
else return $ Just (ak, sk)
where
getEnvKey s = liftIO $ catch (getEnv s) (const $ return "")
{- Stores S3 creds encrypted in the remote's config if possible. -}
s3SetCreds :: RemoteConfig -> Annex RemoteConfig
s3SetCreds c = do
creds <- s3GetCreds c
case creds of
Just (ak, sk) -> do
mcipher <- remoteCipher c
case mcipher of
Just cipher -> do
s <- liftIO $ withEncryptedContent cipher
(return $ L.pack $ unlines [ak, sk])
(return . L.unpack)
return $ M.insert "s3creds" (toB64 s) c
Nothing -> return c
_ -> return c
s3AccessKey :: String
s3AccessKey = "AWS_ACCESS_KEY_ID"
s3SecretKey :: String
s3SecretKey = "AWS_SECRET_ACCESS_KEY"