git-annex/Annex/Version.hs
Joey Hess 13fff71f20 split out three modules from Git
Constructors and configuration make sense in separate modules.
A separate Git.Types is needed to avoid cycles.
2011-12-13 15:06:49 -04:00

44 lines
1 KiB
Haskell

{- git-annex repository versioning
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Annex.Version where
import Common.Annex
import qualified Git.Config
import Config
type Version = String
defaultVersion :: Version
defaultVersion = "3"
supportedVersions :: [Version]
supportedVersions = [defaultVersion]
upgradableVersions :: [Version]
upgradableVersions = ["0", "1", "2"]
versionField :: String
versionField = "annex.version"
getVersion :: Annex (Maybe Version)
getVersion = handle <$> fromRepo (Git.Config.get versionField "")
where
handle [] = Nothing
handle v = Just v
setVersion :: Annex ()
setVersion = setConfig versionField defaultVersion
checkVersion :: Version -> Annex ()
checkVersion v
| v `elem` supportedVersions = return ()
| v `elem` upgradableVersions = err "Upgrade this repository: git-annex upgrade"
| otherwise = err "Upgrade git-annex."
where
err msg = error $ "Repository version " ++ v ++
" is not supported. " ++ msg