git-annex/Database/Export.hs
Joey Hess 9216718fa0
fix one more export conflict false positive
Somehow forgot about the case where the current export db tree is the
same one in the export log, and it warned about an export conflict when
getting a file in that situation. Of course it's no conflict at all!

This commit was sponsored by Jochen Bartl on Patreon.
2019-01-30 13:18:42 -04:00

228 lines
7 KiB
Haskell

{- Sqlite database used for exports to special remotes.
-
- Copyright 2017 Joey Hess <id@joeyh.name>
-:
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE QuasiQuotes, TypeFamilies, TemplateHaskell #-}
{-# LANGUAGE OverloadedStrings, GADTs, FlexibleContexts #-}
{-# LANGUAGE MultiParamTypeClasses, GeneralizedNewtypeDeriving #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE CPP #-}
module Database.Export (
ExportHandle,
openDb,
closeDb,
flushDbQueue,
addExportedLocation,
removeExportedLocation,
getExportedLocation,
isExportDirectoryEmpty,
getExportTreeCurrent,
recordExportTreeCurrent,
getExportTree,
addExportTree,
removeExportTree,
updateExportTree,
updateExportTree',
updateExportTreeFromLog,
ExportedId,
ExportedDirectoryId,
ExportTreeId,
ExportTreeCurrentId,
ExportUpdateResult(..),
) where
import Database.Types
import qualified Database.Queue as H
import Database.Init
import Annex.Locations
import Annex.Common hiding (delete)
import Types.Export
import Annex.Export
import qualified Logs.Export as Log
import Annex.LockFile
import Git.Types
import Git.Sha
import Git.FilePath
import qualified Git.DiffTree
import Database.Persist.Sql hiding (Key)
import Database.Persist.TH
data ExportHandle = ExportHandle H.DbQueue UUID
share [mkPersist sqlSettings, mkMigrate "migrateExport"] [persistLowerCase|
-- Files that have been exported to the remote and are present on it.
Exported
key IKey
file SFilePath
ExportedIndex key file
-- Directories that exist on the remote, and the files that are in them.
ExportedDirectory
subdir SFilePath
file SFilePath
ExportedDirectoryIndex subdir file
-- The content of the tree that has been exported to the remote.
-- Not all of these files are necessarily present on the remote yet.
ExportTree
key IKey
file SFilePath
ExportTreeIndex key file
-- The tree stored in ExportTree
ExportTreeCurrent
tree SRef
UniqueTree tree
|]
{- Opens the database, creating it if it doesn't exist yet.
-
- Only a single process should write to the export at a time, so guard
- any writes with the gitAnnexExportLock.
-}
openDb :: UUID -> Annex ExportHandle
openDb u = do
dbdir <- fromRepo (gitAnnexExportDbDir u)
let db = dbdir </> "db"
unlessM (liftIO $ doesFileExist db) $ do
initDb db $ void $
runMigrationSilent migrateExport
h <- liftIO $ H.openDbQueue H.SingleWriter db "exported"
return $ ExportHandle h u
closeDb :: ExportHandle -> Annex ()
closeDb (ExportHandle h _) = liftIO $ H.closeDbQueue h
queueDb :: ExportHandle -> SqlPersistM () -> IO ()
queueDb (ExportHandle h _) = H.queueDb h checkcommit
where
-- commit queue after 1000 changes
checkcommit sz _lastcommittime
| sz > 1000 = return True
| otherwise = return False
flushDbQueue :: ExportHandle -> IO ()
flushDbQueue (ExportHandle h _) = H.flushDbQueue h
recordExportTreeCurrent :: ExportHandle -> Sha -> IO ()
recordExportTreeCurrent h s = queueDb h $ do
deleteWhere ([] :: [Filter ExportTreeCurrent])
void $ insertUnique $ ExportTreeCurrent $ toSRef s
getExportTreeCurrent :: ExportHandle -> IO (Maybe Sha)
getExportTreeCurrent (ExportHandle h _) = H.queryDbQueue h $ do
l <- selectList ([] :: [Filter ExportTreeCurrent]) []
case l of
(s:[]) -> return $ Just $ fromSRef $ exportTreeCurrentTree $ entityVal s
_ -> return Nothing
addExportedLocation :: ExportHandle -> Key -> ExportLocation -> IO ()
addExportedLocation h k el = queueDb h $ do
void $ insertUnique $ Exported ik ef
let edirs = map
(\ed -> ExportedDirectory (toSFilePath (fromExportDirectory ed)) ef)
(exportDirectories el)
#if MIN_VERSION_persistent(2,8,1)
putMany edirs
#else
mapM_ insertUnique edirs
#endif
where
ik = toIKey k
ef = toSFilePath (fromExportLocation el)
removeExportedLocation :: ExportHandle -> Key -> ExportLocation -> IO ()
removeExportedLocation h k el = queueDb h $ do
deleteWhere [ExportedKey ==. ik, ExportedFile ==. ef]
let subdirs = map (toSFilePath . fromExportDirectory)
(exportDirectories el)
deleteWhere [ExportedDirectoryFile ==. ef, ExportedDirectorySubdir <-. subdirs]
where
ik = toIKey k
ef = toSFilePath (fromExportLocation el)
{- Note that this does not see recently queued changes. -}
getExportedLocation :: ExportHandle -> Key -> IO [ExportLocation]
getExportedLocation (ExportHandle h _) k = H.queryDbQueue h $ do
l <- selectList [ExportedKey ==. ik] []
return $ map (mkExportLocation . fromSFilePath . exportedFile . entityVal) l
where
ik = toIKey k
{- Note that this does not see recently queued changes. -}
isExportDirectoryEmpty :: ExportHandle -> ExportDirectory -> IO Bool
isExportDirectoryEmpty (ExportHandle h _) d = H.queryDbQueue h $ do
l <- selectList [ExportedDirectorySubdir ==. ed] []
return $ null l
where
ed = toSFilePath $ fromExportDirectory d
{- Get locations in the export that might contain a key. -}
getExportTree :: ExportHandle -> Key -> IO [ExportLocation]
getExportTree (ExportHandle h _) k = H.queryDbQueue h $ do
l <- selectList [ExportTreeKey ==. ik] []
return $ map (mkExportLocation . fromSFilePath . exportTreeFile . entityVal) l
where
ik = toIKey k
addExportTree :: ExportHandle -> Key -> ExportLocation -> IO ()
addExportTree h k loc = queueDb h $
void $ insertUnique $ ExportTree ik ef
where
ik = toIKey k
ef = toSFilePath (fromExportLocation loc)
removeExportTree :: ExportHandle -> Key -> ExportLocation -> IO ()
removeExportTree h k loc = queueDb h $
deleteWhere [ExportTreeKey ==. ik, ExportTreeFile ==. ef]
where
ik = toIKey k
ef = toSFilePath (fromExportLocation loc)
{- Diff from the old to the new tree and update the ExportTree table. -}
updateExportTree :: ExportHandle -> Sha -> Sha -> Annex ()
updateExportTree h old new = do
(diff, cleanup) <- inRepo $
Git.DiffTree.diffTreeRecursive old new
forM_ diff $ \i -> do
srcek <- getek (Git.DiffTree.srcsha i)
dstek <- getek (Git.DiffTree.dstsha i)
updateExportTree' h srcek dstek i
void $ liftIO cleanup
where
getek sha
| sha == nullSha = return Nothing
| otherwise = Just <$> exportKey sha
updateExportTree' :: ExportHandle -> Maybe ExportKey -> Maybe ExportKey -> Git.DiffTree.DiffTreeItem -> Annex ()
updateExportTree' h srcek dstek i = do
case srcek of
Nothing -> return ()
Just k -> liftIO $ removeExportTree h (asKey k) loc
case dstek of
Nothing -> return ()
Just k -> liftIO $ addExportTree h (asKey k) loc
where
loc = mkExportLocation $ getTopFilePath $ Git.DiffTree.file i
data ExportUpdateResult = ExportUpdateSuccess | ExportUpdateConflict
deriving (Eq)
updateExportTreeFromLog :: ExportHandle -> Annex ExportUpdateResult
updateExportTreeFromLog db@(ExportHandle _ u) =
withExclusiveLock (gitAnnexExportLock u) $ do
old <- liftIO $ fromMaybe emptyTree
<$> getExportTreeCurrent db
l <- Log.getExport u
case Log.exportedTreeishes l of
[] -> return ExportUpdateSuccess
(new:[])
| new /= old -> do
updateExportTree db old new
liftIO $ recordExportTreeCurrent db new
liftIO $ flushDbQueue db
return ExportUpdateSuccess
| new == old -> return ExportUpdateSuccess
_ts -> return ExportUpdateConflict