{- dropping of unwanted content - - Copyright 2012-2014 Joey Hess - - Licensed under the GNU AGPL version 3 or higher. -} module Annex.Drop where import Annex.Common import qualified Annex import Logs.Trust import Annex.NumCopies import Types.Remote (uuid, appendonly, config) import qualified Remote import qualified Command.Drop import Command import Annex.Wanted import Config import qualified Database.Keys import Git.FilePath import qualified Data.Set as S import System.Log.Logger (debugM) type Reason = String {- Drop a key from local and/or remote when allowed by the preferred content - and numcopies settings. - - Skips trying to drop from remotes that are appendonly, since those drops - would presumably fail. Also skips dropping from exporttree remotes, - which don't allow dropping individual keys. - - The UUIDs are ones where the content is believed to be present. - The Remote list can include other remotes that do not have the content; - only ones that match the UUIDs will be dropped from. - - If allowed to drop fromhere, that drop will be done last. This is done - because local drops do not need any LockedCopy evidence, and so dropping - from local last allows the content to be removed from more remotes. - - A VerifiedCopy can be provided as an optimisation when eg, a key - has just been uploaded to a remote. - - The runner is used to run CommandStart sequentially, it's typically - callCommandAction. -} handleDropsFrom :: [UUID] -> [Remote] -> Reason -> Bool -> Key -> AssociatedFile -> [VerifiedCopy] -> (CommandStart -> CommandCleanup) -> Annex () handleDropsFrom locs rs reason fromhere key afile preverified runner = do g <- Annex.gitRepo l <- map (`fromTopFilePath` g) <$> Database.Keys.getAssociatedFiles key let fs = case afile of AssociatedFile (Just f) -> nub (f : l) AssociatedFile Nothing -> l n <- getcopies fs void $ if fromhere && checkcopies n Nothing then go fs rs n >>= dropl fs else go fs rs n where getcopies fs = do (untrusted, have) <- trustPartition UnTrusted locs numcopies <- if null fs then getNumCopies else maximum <$> mapM getFileNumCopies fs return (NumCopies (length have), numcopies, S.fromList untrusted) {- Check that we have enough copies still to drop the content. - When the remote being dropped from is untrusted, it was not - counted as a copy, so having only numcopies suffices. Otherwise, - we need more than numcopies to safely drop. -} checkcopies (have, numcopies, _untrusted) Nothing = have > numcopies checkcopies (have, numcopies, untrusted) (Just u) | S.member u untrusted = have >= numcopies | otherwise = have > numcopies decrcopies (have, numcopies, untrusted) Nothing = (NumCopies (fromNumCopies have - 1), numcopies, untrusted) decrcopies v@(_have, _numcopies, untrusted) (Just u) | S.member u untrusted = v | otherwise = decrcopies v Nothing go _ [] n = pure n go fs (r:rest) n | uuid r `S.notMember` slocs = go fs rest n | appendonly r = go fs rest n | exportTree (config r) = go fs rest n | checkcopies n (Just $ Remote.uuid r) = dropr fs r n >>= go fs rest | otherwise = pure n checkdrop fs n u a | null fs = check $ -- no associated files; unused content wantDrop True u (Just key) (AssociatedFile Nothing) | otherwise = check $ allM (wantDrop True u (Just key) . AssociatedFile . Just) fs where check c = ifM c ( dodrop n u a , return n ) dodrop n@(have, numcopies, _untrusted) u a = ifM (safely $ runner $ a numcopies) ( do liftIO $ debugM "drop" $ unwords [ "dropped" , case afile of AssociatedFile Nothing -> serializeKey key AssociatedFile (Just af) -> af , "(from " ++ maybe "here" show u ++ ")" , "(copies now " ++ show (fromNumCopies have - 1) ++ ")" , ": " ++ reason ] return $ decrcopies n u , return n ) dropl fs n = checkdrop fs n Nothing $ \numcopies -> Command.Drop.startLocal afile ai numcopies key preverified dropr fs r n = checkdrop fs n (Just $ Remote.uuid r) $ \numcopies -> Command.Drop.startRemote afile ai numcopies key r ai = mkActionItem (key, afile) slocs = S.fromList locs safely a = either (const False) id <$> tryNonAsync a