git-annex/Annex/UUID.hs
Joey Hess a1730cd6af
adeiu, MissingH
Removed dependency on MissingH, instead depending on the split
library.

After laying groundwork for this since 2015, it
was mostly straightforward. Added Utility.Tuple and
Utility.Split. Eyeballed System.Path.WildMatch while implementing
the same thing.

Since MissingH's progress meter display was being used, I re-implemented
my own. Bonus: Now progress is displayed for transfers of files of
unknown size.

This commit was sponsored by Shane-o on Patreon.
2017-05-16 01:03:52 -04:00

124 lines
3.2 KiB
Haskell

{- git-annex uuids
-
- Each git repository used by git-annex has an annex.uuid setting that
- uniquely identifies that repository.
-
- UUIDs of remotes are cached in git config, using keys named
- remote.<name>.annex-uuid
-
- Copyright 2010-2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Annex.UUID (
getUUID,
getRepoUUID,
getUncachedUUID,
isUUIDConfigured,
prepUUID,
genUUID,
genUUIDInNameSpace,
gCryptNameSpace,
removeRepoUUID,
storeUUID,
storeUUIDIn,
setUUID,
webUUID,
bitTorrentUUID,
) where
import Annex.Common
import qualified Annex
import qualified Git
import qualified Git.Config
import Config
import qualified Data.UUID as U
import qualified Data.UUID.V4 as U4
import qualified Data.UUID.V5 as U5
import Utility.FileSystemEncoding
configkey :: ConfigKey
configkey = annexConfig "uuid"
{- Generates a random UUID, that does not include the MAC address. -}
genUUID :: IO UUID
genUUID = UUID . show <$> U4.nextRandom
{- Generates a UUID from a given string, using a namespace.
- Given the same namespace, the same string will always result
- in the same UUID. -}
genUUIDInNameSpace :: U.UUID -> String -> UUID
genUUIDInNameSpace namespace = UUID . show . U5.generateNamed namespace . s2w8
{- Namespace used for UUIDs derived from git-remote-gcrypt ids. -}
gCryptNameSpace :: U.UUID
gCryptNameSpace = U5.generateNamed U5.namespaceURL $
s2w8 "http://git-annex.branchable.com/design/gcrypt/"
{- Get current repository's UUID. -}
getUUID :: Annex UUID
getUUID = annexUUID <$> Annex.getGitConfig
{- Looks up a remote repo's UUID, caching it in .git/config if
- it's not already. -}
getRepoUUID :: Git.Repo -> Annex UUID
getRepoUUID r = do
c <- toUUID <$> getConfig cachekey ""
let u = getUncachedUUID r
if c /= u && u /= NoUUID
then do
updatecache u
return u
else return c
where
updatecache u = do
g <- gitRepo
when (g /= r) $ storeUUIDIn cachekey u
cachekey = remoteConfig r "uuid"
removeRepoUUID :: Annex ()
removeRepoUUID = do
unsetConfig configkey
storeUUID NoUUID
getUncachedUUID :: Git.Repo -> UUID
getUncachedUUID = toUUID . Git.Config.get key ""
where
(ConfigKey key) = configkey
-- Does the repo's config have a key for the UUID?
-- True even when the key has no value.
isUUIDConfigured :: Git.Repo -> Bool
isUUIDConfigured = isJust . Git.Config.getMaybe key
where
(ConfigKey key) = configkey
{- Make sure that the repo has an annex.uuid setting. -}
prepUUID :: Annex ()
prepUUID = whenM ((==) NoUUID <$> getUUID) $
storeUUID =<< liftIO genUUID
storeUUID :: UUID -> Annex ()
storeUUID u = do
Annex.changeGitConfig $ \c -> c { annexUUID = u }
storeUUIDIn configkey u
storeUUIDIn :: ConfigKey -> UUID -> Annex ()
storeUUIDIn configfield = setConfig configfield . fromUUID
{- Only sets the configkey in the Repo; does not change .git/config -}
setUUID :: Git.Repo -> UUID -> IO Git.Repo
setUUID r u = do
let s = show configkey ++ "=" ++ fromUUID u
Git.Config.store s r
-- Dummy uuid for the whole web. Do not alter.
webUUID :: UUID
webUUID = UUID "00000000-0000-0000-0000-000000000001"
-- Dummy uuid for bittorrent. Do not alter.
bitTorrentUUID :: UUID
bitTorrentUUID = UUID "00000000-0000-0000-0000-000000000002"