git-annex/Annex/Branch/Transitions.hs
Joey Hess 1da9fe5bd8
implemented filter-branch for key info
Not tested yet but should work.

Noted a possible optimisation, which should probably be added, to
speed it up in cases where there is no uuid filtering being done.
It would need Annex.Branch to add a function like getRef that uses
catFileDetails, so the sha is also returned. The difficulty would be
making it support the precached file content; if it didn't it would
probably not be any faster and could even be slower. So probably the
precaching would need to be changed to also cache the sha.
2021-05-17 11:11:39 -04:00

114 lines
4.2 KiB
Haskell

{- git-annex branch transitions
-
- Copyright 2013-2021 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Annex.Branch.Transitions (
FileTransition(..),
getTransitionCalculator,
filterBranch,
) where
import Common
import Logs
import Logs.Transitions
import qualified Logs.UUIDBased as UUIDBased
import qualified Logs.Presence.Pure as Presence
import qualified Logs.Chunk.Pure as Chunk
import qualified Logs.MetaData.Pure as MetaData
import qualified Logs.Remote.Pure as Remote
import Types.TrustLevel
import Types.UUID
import Types.MetaData
import Types.Remote
import Types.GitConfig (GitConfig)
import Types.ProposedAccepted
import Annex.SpecialRemote.Config
import qualified Data.Map as M
import qualified Data.Set as S
import qualified Data.ByteString.Lazy as L
import qualified Data.Attoparsec.ByteString.Lazy as A
import Data.ByteString.Builder
data FileTransition
= ChangeFile Builder
| PreserveFile
type TransitionCalculator = GitConfig -> RawFilePath -> L.ByteString -> FileTransition
getTransitionCalculator :: Transition -> Maybe (TrustMap -> M.Map UUID RemoteConfig -> TransitionCalculator)
getTransitionCalculator ForgetGitHistory = Nothing
getTransitionCalculator ForgetDeadRemotes = Just dropDead
-- Removes data about all dead repos.
--
-- The trust log is not changed, because other, unmerged clones
-- may contain other data about the dead repos. So we need to remember
-- which are dead to later remove that.
--
-- When the remote log contains a sameas-uuid pointing to a dead uuid,
-- the uuid of that remote configuration is also effectively dead,
-- though not in the trust log. There may be per-remote state stored using
-- the latter uuid, that also needs to be removed. The sameas-uuid
-- is not removed from the remote log, for the same reason the trust log
-- is not changed.
dropDead :: TrustMap -> M.Map UUID RemoteConfig -> TransitionCalculator
dropDead trustmap remoteconfigmap gc f content
| f == trustLog = PreserveFile
| f == remoteLog = ChangeFile $
Remote.buildRemoteConfigLog $
M.mapWithKey minimizesameasdead $
filterMapLog (notdead trustmap) id $
Remote.parseRemoteConfigLog content
| otherwise = filterBranch (notdead trustmap') gc f content
where
notdead m u = M.findWithDefault def u m /= DeadTrusted
trustmap' = trustmap `M.union`
M.map (const DeadTrusted) (M.filter sameasdead remoteconfigmap)
sameasdead cm =
case toUUID . fromProposedAccepted <$> M.lookup sameasUUIDField cm of
Nothing -> False
Just u' -> M.lookup u' trustmap == Just DeadTrusted
minimizesameasdead u l
| M.lookup u trustmap' == Just DeadTrusted =
l { UUIDBased.value = minimizesameasdead' (UUIDBased.value l) }
| otherwise = l
minimizesameasdead' c = M.restrictKeys c (S.singleton sameasUUIDField)
filterBranch :: (UUID -> Bool) -> TransitionCalculator
filterBranch wantuuid gc f content = case getLogVariety gc f of
Just OldUUIDBasedLog -> ChangeFile $
UUIDBased.buildLogOld byteString $
filterMapLog wantuuid id $
UUIDBased.parseLogOld A.takeByteString content
Just NewUUIDBasedLog -> ChangeFile $
UUIDBased.buildLogNew byteString $
filterMapLog wantuuid id $
UUIDBased.parseLogNew A.takeByteString content
Just (ChunkLog _) -> ChangeFile $
Chunk.buildLog $ filterMapLog wantuuid fst $
Chunk.parseLog content
Just (LocationLog _) -> ChangeFile $ Presence.buildLog $
Presence.compactLog $
filterLocationLog wantuuid $
Presence.parseLog content
Just (UrlLog _) -> PreserveFile
Just RemoteMetaDataLog -> ChangeFile $ MetaData.buildLog $
filterRemoteMetaDataLog wantuuid $
MetaData.simplifyLog $ MetaData.parseLog content
Just OtherLog -> PreserveFile
Nothing -> PreserveFile
filterMapLog :: (UUID -> Bool) -> (k -> UUID) -> M.Map k v -> M.Map k v
filterMapLog wantuuid getuuid = M.filterWithKey $ \k _v -> wantuuid (getuuid k)
filterLocationLog :: (UUID -> Bool) -> [Presence.LogLine] -> [Presence.LogLine]
filterLocationLog wantuuid = filter $
wantuuid . toUUID . Presence.fromLogInfo . Presence.info
filterRemoteMetaDataLog :: (UUID -> Bool) -> MetaData.Log MetaData -> MetaData.Log MetaData
filterRemoteMetaDataLog wantuuid =
MetaData.filterOutEmpty . MetaData.filterRemoteMetaData wantuuid