git-annex/Upgrade/V1.hs

240 lines
6.7 KiB
Haskell

{- git-annex v1 -> v2 upgrade support
-
- Copyright 2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Upgrade.V1 where
import System.IO.Error (try)
import System.Directory
import Control.Monad.State (liftIO)
import Control.Monad (filterM, forM_, unless)
import System.Posix.Files
import System.FilePath
import Data.String.Utils
import System.Posix.Types
import Data.Maybe
import Data.Char
import Key
import Content
import Types
import Locations
import LocationLog
import qualified Annex
import qualified GitRepo as Git
import Backend
import Messages
import Version
import Utility
import qualified Command.Init
-- v2 adds hashing of filenames of content and location log files.
-- Key information is encoded in filenames differently, so
-- both content and location log files move around, and symlinks
-- to content need to be changed.
--
-- When upgrading a v1 key to v2, file size metadata ought to be
-- added to the key (unless it is a WORM key, which encoded
-- mtime:size in v1). This can only be done when the file content
-- is present. Since upgrades need to happen consistently,
-- (so that two repos get changed the same way by the upgrade, and
-- will merge), that metadata cannot be added on upgrade.
--
-- Note that file size metadata
-- will only be used for detecting situations where git-annex
-- would run out of disk space, so if some keys don't have it,
-- the impact is minor. At least initially. It could be used in the
-- future by smart auto-repo balancing code, etc.
--
-- Anyway, since v2 plans ahead for other metadata being included
-- in keys, there should probably be a way to update a key.
-- Something similar to the migrate subcommand could be used,
-- and users could then run that at their leisure.
upgrade :: Annex Bool
upgrade = do
showNote "v1 to v2"
g <- Annex.gitRepo
if Git.repoIsLocalBare g
then do
moveContent
setVersion
else do
moveContent
updateSymlinks
moveLocationLogs
Annex.queueRun
setVersion
-- add new line to auto-merge hashed location logs
-- this commits, so has to come after the upgrade
liftIO $ Command.Init.gitAttributesWrite g
return True
moveContent :: Annex ()
moveContent = do
showNote "moving content..."
files <- getKeyFilesPresent1
forM_ files move
where
move f = do
let k = fileKey1 (takeFileName f)
let d = parentDir f
liftIO $ allowWrite d
liftIO $ allowWrite f
moveAnnex k f
liftIO $ removeDirectory d
updateSymlinks :: Annex ()
updateSymlinks = do
showNote "updating symlinks..."
g <- Annex.gitRepo
files <- liftIO $ Git.inRepo g [Git.workTree g]
forM_ files $ fixlink
where
fixlink f = do
r <- lookupFile1 f
case r of
Nothing -> return ()
Just (k, _) -> do
link <- calcGitLink f k
liftIO $ removeFile f
liftIO $ createSymbolicLink link f
Annex.queue "add" [Param "--"] f
Annex.queueRunAt 10240
moveLocationLogs :: Annex ()
moveLocationLogs = do
showNote "moving location logs..."
logkeys <- oldlocationlogs
forM_ logkeys move
where
oldlocationlogs = do
g <- Annex.gitRepo
let dir = gitStateDir g
exists <- liftIO $ doesDirectoryExist dir
if exists
then do
contents <- liftIO $ getDirectoryContents dir
return $ catMaybes $ map oldlog2key contents
else return []
move (l, k) = do
g <- Annex.gitRepo
let dest = logFile g k
let dir = gitStateDir g
let f = dir </> l
liftIO $ createDirectoryIfMissing True (parentDir dest)
-- could just git mv, but this way deals with
-- log files that are not checked into git,
-- as well as merging with already upgraded
-- logs that have been pulled from elsewhere
old <- liftIO $ readLog f
new <- liftIO $ readLog dest
liftIO $ writeLog dest (old++new)
Annex.queue "add" [Param "--"] dest
Annex.queue "add" [Param "--"] f
Annex.queue "rm" [Param "--quiet", Param "-f", Param "--"] f
Annex.queueRunAt 10240
oldlog2key :: FilePath -> Maybe (FilePath, Key)
oldlog2key l =
let len = length l - 4 in
if drop len l == ".log"
then let k = readKey1 (take len l) in
if null (keyName k) || null (keyBackendName k)
then Nothing
else Just (l, k)
else Nothing
-- WORM backend keys: "WORM:mtime:size:filename"
-- all the rest: "backend:key"
--
-- If the file looks like "WORM:XXX-...", then it was created by mixing
-- v2 and v1; that infelicity is worked around by treating the value
-- as the v2 key that it is.
readKey1 :: String -> Key
readKey1 v =
if mixup
then fromJust $ readKey $ join ":" $ tail bits
else Key { keyName = n , keyBackendName = b, keySize = s, keyMtime = t }
where
bits = split ":" v
b = head bits
n = join ":" $ drop (if wormy then 3 else 1) bits
t = if wormy
then Just (read (bits !! 1) :: EpochTime)
else Nothing
s = if wormy
then Just (read (bits !! 2) :: Integer)
else Nothing
wormy = head bits == "WORM"
mixup = wormy && (isUpper $ head $ bits !! 1)
showKey1 :: Key -> String
showKey1 Key { keyName = n , keyBackendName = b, keySize = s, keyMtime = t } =
join ":" $ filter (not . null) [b, showifhere t, showifhere s, n]
where
showifhere Nothing = ""
showifhere (Just v) = show v
keyFile1 :: Key -> FilePath
keyFile1 key = replace "/" "%" $ replace "%" "&s" $ replace "&" "&a" $ showKey1 key
fileKey1 :: FilePath -> Key
fileKey1 file = readKey1 $
replace "&a" "&" $ replace "&s" "%" $ replace "%" "/" file
logFile1 :: Git.Repo -> Key -> String
logFile1 repo key = gitStateDir repo ++ keyFile1 key ++ ".log"
lookupFile1 :: FilePath -> Annex (Maybe (Key, Backend Annex))
lookupFile1 file = do
bs <- Annex.getState Annex.supportedBackends
tl <- liftIO $ try getsymlink
case tl of
Left _ -> return Nothing
Right l -> makekey bs l
where
getsymlink = do
l <- readSymbolicLink file
return $ takeFileName l
makekey bs l = do
case maybeLookupBackendName bs bname of
Nothing -> do
unless (null kname || null bname ||
not (isLinkToAnnex l)) $
warning skip
return Nothing
Just backend -> return $ Just (k, backend)
where
k = fileKey1 l
bname = keyBackendName k
kname = keyName k
skip = "skipping " ++ file ++
" (unknown backend " ++ bname ++ ")"
getKeyFilesPresent1 :: Annex [FilePath]
getKeyFilesPresent1 = do
g <- Annex.gitRepo
getKeyFilesPresent1' $ gitAnnexObjectDir g
getKeyFilesPresent1' :: FilePath -> Annex [FilePath]
getKeyFilesPresent1' dir = do
exists <- liftIO $ doesDirectoryExist dir
if (not exists)
then return []
else do
dirs <- liftIO $ getDirectoryContents dir
let files = map (\d -> dir ++ "/" ++ d ++ "/" ++ takeFileName d) dirs
liftIO $ filterM present files
where
present f = do
result <- try $ getFileStatus f
case result of
Right s -> return $ isRegularFile s
Left _ -> return False