git-annex/Logs/UUID.hs
Joey Hess a194e88a62
invalidate caches after log changes
This seems like something Annex.Sim would need to happen. And generally
a really good idea.
2024-09-20 16:52:17 -04:00

73 lines
2.2 KiB
Haskell

{- git-annex uuid log
-
- uuid.log stores a list of known uuids, and their descriptions.
-
- Copyright 2010-2023 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Logs.UUID (
uuidLog,
describeUUID,
uuidDescMap,
uuidDescMapLoad,
uuidDescMapRaw,
) where
import Types.UUID
import Annex.Common
import Annex.VectorClock
import qualified Annex
import qualified Annex.Branch
import Logs
import Logs.UUIDBased
import qualified Annex.UUID
import qualified Data.Map.Strict as M
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as L
import qualified Data.Attoparsec.ByteString.Lazy as A
import Data.ByteString.Builder
import Data.Char
{- Records a description for a uuid in the log. -}
describeUUID :: UUID -> UUIDDesc -> Annex ()
describeUUID uuid desc = do
c <- currentVectorClock
Annex.Branch.change (Annex.Branch.RegardingUUID [uuid]) uuidLog $
buildLogOld builder . changeLog c uuid desc . parseUUIDLog
Annex.changeState $ \s -> s { Annex.uuiddescmap = Nothing }
where
builder (UUIDDesc b) = byteString (escnewline b)
-- Escape any newline in the description, since newlines cannot
-- be present in the logged value. This is a one-way escaping.
escnewline = B.intercalate "\\n" . B.split newline
newline = fromIntegral (ord '\n')
{- The map is cached for speed. -}
uuidDescMap :: Annex UUIDDescMap
uuidDescMap = maybe uuidDescMapLoad return =<< Annex.getState Annex.uuiddescmap
{- Read the uuidLog into a map, and cache it for later use.
-
- If the current repository has not been described, it is still included
- in the map with an empty description. -}
uuidDescMapLoad :: Annex UUIDDescMap
uuidDescMapLoad = do
m <- uuidDescMapRaw
u <- Annex.UUID.getUUID
let m' = M.insertWith preferold u mempty m
Annex.changeState $ \s -> s { Annex.uuiddescmap = Just m' }
return m'
where
preferold = flip const
{- Read the uuidLog into a map. Includes only actually set descriptions. -}
uuidDescMapRaw :: Annex UUIDDescMap
uuidDescMapRaw = simpleMap . parseUUIDLog <$> Annex.Branch.get uuidLog
parseUUIDLog :: L.ByteString -> Log UUIDDesc
parseUUIDLog = parseLogOld (UUIDDesc <$> A.takeByteString)