split out raw sql interface

Database/Keys/SQL.hs

@@ -0,0 +1,100 @@
+{- Sqlite database of information about Keys
+ -
+ - Copyright 2015-2016 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, ScopedTypeVariables #-}
+
+module Database.Keys.SQL where
+
+import Database.Types
+import qualified Database.Queue as H
+import Utility.InodeCache
+import Git.FilePath
+
+import Database.Persist.TH
+import Database.Esqueleto hiding (Key)
+import Data.Time.Clock
+import Control.Monad
+
+share [mkPersist sqlSettings, mkMigrate "migrateKeysDb"] [persistLowerCase|
+Associated
+  key SKey
+  file FilePath
+  KeyFileIndex key file
+Content
+  key SKey
+  cache SInodeCache
+  KeyCacheIndex key cache
+|]
+
+newtype ReadHandle = ReadHandle H.DbQueue
+
+readDb :: SqlPersistM a -> ReadHandle -> IO a
+readDb a (ReadHandle h) = H.queryDbQueue h a
+
+newtype WriteHandle = WriteHandle H.DbQueue
+
+queueDb :: SqlPersistM () -> WriteHandle -> IO ()
+queueDb a (WriteHandle h) = H.queueDb h checkcommit a
+  where
+	-- commit queue after 1000 changes or 5 minutes, whichever comes first
+	checkcommit sz lastcommittime
+		| sz > 1000 = return True
+		| otherwise = do
+			now <- getCurrentTime
+			return $ diffUTCTime lastcommittime now > 300
+
+addAssociatedFile :: SKey -> TopFilePath -> WriteHandle -> IO ()
+addAssociatedFile sk f = queueDb $ do
+	-- If the same file was associated with a different key before,
+	-- remove that.
+	delete $ from $ \r -> do
+		where_ (r ^. AssociatedFile ==. val (getTopFilePath f) &&. not_ (r ^. AssociatedKey ==. val sk))
+	void $ insertUnique $ Associated sk (getTopFilePath f)
+
+{- Note that the files returned were once associated with the key, but
+ - some of them may not be any longer. -}
+getAssociatedFiles :: SKey -> ReadHandle -> IO [TopFilePath]
+getAssociatedFiles sk = readDb $ do
+	l <- select $ from $ \r -> do
+		where_ (r ^. AssociatedKey ==. val sk)
+		return (r ^. AssociatedFile)
+	return $ map (asTopFilePath . unValue) l
+
+{- Gets any keys that are on record as having a particular associated file.
+ - (Should be one or none but the database doesn't enforce that.) -}
+getAssociatedKey :: TopFilePath -> ReadHandle -> IO [SKey]
+getAssociatedKey f = readDb $ do
+	l <- select $ from $ \r -> do
+		where_ (r ^. AssociatedFile ==. val (getTopFilePath f))
+		return (r ^. AssociatedKey)
+	return $ map unValue l
+
+removeAssociatedFile :: SKey -> TopFilePath -> WriteHandle -> IO ()
+removeAssociatedFile sk f = queueDb $ 
+	delete $ from $ \r -> do
+		where_ (r ^. AssociatedKey ==. val sk &&. r ^. AssociatedFile ==. val (getTopFilePath f))
+
+addInodeCaches :: SKey -> [InodeCache] -> WriteHandle -> IO ()
+addInodeCaches sk is = queueDb $
+	forM_ is $ \i -> insertUnique $ Content sk (toSInodeCache i)
+
+{- A key may have multiple InodeCaches; one for the annex object, and one
+ - for each pointer file that is a copy of it. -}
+getInodeCaches :: SKey -> ReadHandle -> IO [InodeCache]
+getInodeCaches sk = readDb $ do
+	l <- select $ from $ \r -> do
+		where_ (r ^. ContentKey ==. val sk)
+		return (r ^. ContentCache)
+	return $ map (fromSInodeCache . unValue) l
+
+removeInodeCaches :: SKey -> WriteHandle -> IO ()
+removeInodeCaches sk = queueDb $ 
+	delete $ from $ \r -> do
+		where_ (r ^. ContentKey ==. val sk)