git-annex/LocationLog.hs
Joey Hess 9f1577f746 remove unused backend machinery
The only remaining vestiage of backends is different types of keys. These
are still called "backends", mostly to avoid needing to change user interface
and configuration. But everything to do with storing keys in different
backends was gone; instead different types of remotes are used.

In the refactoring, lots of code was moved out of odd corners like
Backend.File, to closer to where it's used, like Command.Drop and
Command.Fsck. Quite a lot of dead code was removed. Several data structures
became simpler, which may result in better runtime efficiency. There should
be no user-visible changes.
2011-07-05 19:57:46 -04:00

66 lines
1.7 KiB
Haskell

{- git-annex location log
-
- git-annex keeps track of which repositories have the contents of annexed
- files.
-
- Repositories record their UUID and the date when they --get or --drop
- a value.
-
- Copyright 2010-2011 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module LocationLog (
LogStatus(..),
logChange,
readLog,
writeLog,
keyLocations,
loggedKeys,
logFile,
logFileKey
) where
import System.FilePath
import Control.Monad (when)
import Data.Maybe
import qualified Git
import qualified Branch
import UUID
import Types
import Types.Key
import Locations
import PresenceLog
{- Log a change in the presence of a key's value in a repository. -}
logChange :: Git.Repo -> Key -> UUID -> LogStatus -> Annex ()
logChange repo key u s = do
when (null u) $
error $ "unknown UUID for " ++ Git.repoDescribe repo ++
" (have you run git annex init there?)"
addLog (logFile key) =<< logNow s u
{- Returns a list of repository UUIDs that, according to the log, have
- the value of a key. -}
keyLocations :: Key -> Annex [UUID]
keyLocations key = currentLog $ logFile key
{- Finds all keys that have location log information.
- (There may be duplicate keys in the list.) -}
loggedKeys :: Annex [Key]
loggedKeys =
return . catMaybes . map (logFileKey . takeFileName) =<< Branch.files
{- The filename of the log file for a given key. -}
logFile :: Key -> String
logFile key = hashDirLower key ++ keyFile key ++ ".log"
{- Converts a log filename into a key. -}
logFileKey :: FilePath -> Maybe Key
logFileKey file
| end == ".log" = readKey beginning
| otherwise = Nothing
where
(beginning, end) = splitAt (length file - 4) file