git-annex/Logs/Group.hs
Joey Hess 62beaa1a86 refactor git-annex branch log filename code into central location
Having one module that knows about all the filenames used on the branch
allows working back from an arbitrary filename to enough information about
it to implement dropping dead remotes and doing other log file compacting
as part of a forget transition.
2013-08-29 19:13:00 -04:00

83 lines
2.3 KiB
Haskell

{- git-annex group log
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Logs.Group (
groupLog,
groupChange,
groupSet,
lookupGroups,
groupMap,
groupMapLoad,
getStandardGroup,
inUnwantedGroup
) where
import qualified Data.Map as M
import qualified Data.Set as S
import Data.Time.Clock.POSIX
import Common.Annex
import Logs
import qualified Annex.Branch
import qualified Annex
import Logs.UUIDBased
import Types.Group
import Types.StandardGroups
{- Returns the groups of a given repo UUID. -}
lookupGroups :: UUID -> Annex (S.Set Group)
lookupGroups u = (fromMaybe S.empty . M.lookup u) . groupsByUUID <$> groupMap
{- Applies a set modifier to change the groups for a uuid in the groupLog. -}
groupChange :: UUID -> (S.Set Group -> S.Set Group) -> Annex ()
groupChange uuid@(UUID _) modifier = do
curr <- lookupGroups uuid
ts <- liftIO getPOSIXTime
Annex.Branch.change groupLog $
showLog (unwords . S.toList) .
changeLog ts uuid (modifier curr) .
parseLog (Just . S.fromList . words)
-- The changed group invalidates the preferred content cache.
Annex.changeState $ \s -> s
{ Annex.groupmap = Nothing
, Annex.preferredcontentmap = Nothing
}
groupChange NoUUID _ = error "unknown UUID; cannot modify"
groupSet :: UUID -> S.Set Group -> Annex ()
groupSet u g = groupChange u (const g)
{- The map is cached for speed. -}
groupMap :: Annex GroupMap
groupMap = maybe groupMapLoad return =<< Annex.getState Annex.groupmap
{- Loads the map, updating the cache. -}
groupMapLoad :: Annex GroupMap
groupMapLoad = do
m <- makeGroupMap . simpleMap .
parseLog (Just . S.fromList . words) <$>
Annex.Branch.get groupLog
Annex.changeState $ \s -> s { Annex.groupmap = Just m }
return m
makeGroupMap :: M.Map UUID (S.Set Group) -> GroupMap
makeGroupMap byuuid = GroupMap byuuid bygroup
where
bygroup = M.fromListWith S.union $
concatMap explode $ M.toList byuuid
explode (u, s) = map (\g -> (g, S.singleton u)) (S.toList s)
{- If a repository is in exactly one standard group, returns it. -}
getStandardGroup :: S.Set Group -> Maybe StandardGroup
getStandardGroup s = case mapMaybe toStandardGroup $ S.toList s of
[g] -> Just g
_ -> Nothing
inUnwantedGroup :: UUID -> Annex Bool
inUnwantedGroup u = elem UnwantedGroup
. mapMaybe toStandardGroup . S.toList <$> lookupGroups u