prevent numcopies or mincopies being configured to 0

Ignore annex.numcopies set to 0 in gitattributes or git config, or by
git-annex numcopies or by --numcopies, since that configuration would make
git-annex easily lose data. Same for mincopies.

This is a continuation of the work to make data only be able to be lost
when --force is used. It earlier led to the --trust option being disabled,
and similar reasoning applies here.

Most numcopies configs had docs that strongly discouraged setting it to 0
anyway. And I can't imagine a use case for setting to 0. Not that there
might not be one, but it's just so far from the intended use case of
git-annex, of managing and storing your data, that it does not seem like
it makes sense to cater to such a hypothetical use case, where any
git-annex drop can lose your data at any time.

Using a smart constructor makes sure every place avoids 0. Note that this
does mean that NumCopies is for the configured desired values, and not the
actual existing number of copies, which of course can be 0. The name
configuredNumCopies is used to make that clear.

Sponsored-by: Brock Spratlen on Patreon

diff --git a/Annex/Drop.hs b/Annex/Drop.hs
index 2822f0be256f45ba9d61bf8595973a3cbe1ccf38..f59d6f17d6ea26abbee4ec6887db369d864bc65d 100644 (file)
--- a/Annex/Drop.hs
+++ b/Annex/Drop.hs
@@ -70,10 +70,10 @@ handleDropsFrom locs rs reason fromhere key afile si preverified runner = do
         - will surely fail.
         -}
        checkcopies (have, numcopies, mincopies, _untrusted) Nothing =
-               NumCopies have > numcopies && MinCopies have > mincopies
+               have > fromNumCopies numcopies && have > fromMinCopies mincopies
        checkcopies (have, numcopies, mincopies, untrusted) (Just u)
-               | S.member u untrusted = NumCopies have >= numcopies && MinCopies have >= mincopies
-               | otherwise = NumCopies have > numcopies && MinCopies have > mincopies
+               | S.member u untrusted = have >= fromNumCopies numcopies && have >= fromMinCopies mincopies
+               | otherwise = have > fromNumCopies numcopies && have > fromMinCopies mincopies
        
        decrcopies (have, numcopies, mincopies, untrusted) Nothing =
                (have - 1, numcopies, mincopies, untrusted)

diff --git a/Annex/NumCopies.hs b/Annex/NumCopies.hs
index a912028930e51a1989715457aaec180bf312965a..d460856465facb9acf0d9a6c2f75c287232f203f 100644 (file)
--- a/Annex/NumCopies.hs
+++ b/Annex/NumCopies.hs
@@ -43,10 +43,10 @@ import qualified Control.Monad.Catch as M
 import Data.Typeable
 
 defaultNumCopies :: NumCopies
-defaultNumCopies = NumCopies 1
+defaultNumCopies = configuredNumCopies 1
 
 defaultMinCopies :: MinCopies
-defaultMinCopies = MinCopies 1
+defaultMinCopies = configuredMinCopies 1
 
 fromSourcesOr :: v -> [Annex (Maybe v)] -> Annex v
 fromSourcesOr v = fromMaybe v <$$> getM id
@@ -178,8 +178,8 @@ getNumMinCopiesAttr :: RawFilePath  -> Annex (Maybe NumCopies, Maybe MinCopies)
 getNumMinCopiesAttr file =
        checkAttrs ["annex.numcopies", "annex.mincopies"] file >>= \case
                (n:m:[]) -> return
-                       ( NumCopies <$> readish n
-                       , MinCopies <$> readish m
+                       ( configuredNumCopies <$> readish n
+                       , configuredMinCopies <$> readish m
                        )
                _ -> error "internal"
 
@@ -197,8 +197,8 @@ numCopiesCheck file key vs = do
 
 numCopiesCheck' :: RawFilePath -> (Int -> Int -> v) -> [UUID] -> Annex v
 numCopiesCheck' file vs have = do
-       NumCopies needed <- fst <$> getFileNumMinCopies file
-       return $ length have `vs` needed
+       needed <- fst <$> getFileNumMinCopies file
+       return $ length have `vs` fromNumCopies needed
 
 data UnVerifiedCopy = UnVerifiedRemote Remote | UnVerifiedHere
        deriving (Ord, Eq)

diff --git a/Assistant/WebApp/Configurators/Preferences.hs b/Assistant/WebApp/Configurators/Preferences.hs
index 653a1fc3915b6e58ce20b35561cb2ce57d5b6d4a..14b3267b1c7843150c334c2c3cdbc3a0e10c8c0f 100644 (file)
--- a/Assistant/WebApp/Configurators/Preferences.hs
+++ b/Assistant/WebApp/Configurators/Preferences.hs
@@ -85,7 +85,7 @@ getPrefs = PrefsForm
 storePrefs :: PrefsForm -> Annex ()
 storePrefs p = do
        setConfig (annexConfig "diskreserve") (T.unpack $ diskReserve p)
-       setGlobalNumCopies (NumCopies $ numCopies p)
+       setGlobalNumCopies (configuredNumCopies $ numCopies p)
        unsetConfig (annexConfig "numcopies") -- deprecated
        setConfig (annexConfig "autoupgrade") (fromAutoUpgrade $ autoUpgrade p)
        unlessM ((==) <$> pure (autoStart p) <*> inAutoStartFile) $ do

diff --git a/CHANGELOG b/CHANGELOG
index 875d400b18cdf89ebb1db41504777cb7ad9a09c0..f7972935bd04f0b1367649f2148a53678a5aac73 100644 (file)
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,12 @@
+git-annex (10.20220323) UNRELEASED; urgency=medium
+
+  * Ignore annex.numcopies set to 0 in gitattributes or git config,
+    or by git-annex numcopies or by --numcopies, since that
+    configuration would make git-annex easily lose data. 
+    Same for mincopies.
+
+ -- Joey Hess <id@joeyh.name>  Mon, 28 Mar 2022 14:46:10 -0400
+
 git-annex (10.20220322) upstream; urgency=medium
 
   * Directory special remotes with importtree=yes have changed to once more 

diff --git a/CmdLine/GitAnnex/Options.hs b/CmdLine/GitAnnex/Options.hs
index ab7331b95723a87977f5c66f0ce19446ead7504c..49848b7786ace65e5cbf81314a6c130644b29b9b 100644 (file)
--- a/CmdLine/GitAnnex/Options.hs
+++ b/CmdLine/GitAnnex/Options.hs
@@ -100,8 +100,8 @@ gitAnnexGlobalOptions = commonGlobalOptions ++
                )
        ]
   where
-       setnumcopies n = Annex.changeState $ \s -> s { Annex.forcenumcopies = Just $ NumCopies n }
-       setmincopies n = Annex.changeState $ \s -> s { Annex.forcemincopies = Just $ MinCopies n }
+       setnumcopies n = Annex.changeState $ \s -> s { Annex.forcenumcopies = Just $ configuredNumCopies n }
+       setmincopies n = Annex.changeState $ \s -> s { Annex.forcemincopies = Just $ configuredMinCopies n }
        setuseragent v = Annex.changeState $ \s -> s { Annex.useragent = Just v }
        setgitconfig v = Annex.addGitConfigOverride v
        setdesktopnotify v = Annex.changeState $ \s -> s { Annex.desktopnotify = Annex.desktopnotify s <> v }

diff --git a/Command/Drop.hs b/Command/Drop.hs
index b5774b999f285b1c1da103197061380acef5d11a..f397068ae884e382c56a5546e16e86f8862224d1 100644 (file)
--- a/Command/Drop.hs
+++ b/Command/Drop.hs
@@ -252,7 +252,7 @@ checkDropAuto automode mremote afile key a =
                        uuid <- getUUID
                        let remoteuuid = fromMaybe uuid $ Remote.uuid <$> mremote
                        locs' <- trustExclude UnTrusted $ filter (/= remoteuuid) locs
-                       if NumCopies (length locs') >= numcopies
+                       if length locs' >= fromNumCopies numcopies
                                then a numcopies mincopies
                                else stop
                | otherwise = a numcopies mincopies

diff --git a/Command/Fsck.hs b/Command/Fsck.hs
index 6ab159e10548c40e74cd6d3a34e1ddf54843914b..4de157943f2177ba62a97234629d68bf3e41deb4 100644 (file)
--- a/Command/Fsck.hs
+++ b/Command/Fsck.hs
@@ -517,8 +517,8 @@ checkKeyNumCopies key afile numcopies = do
        locs <- loggedLocations key
        (untrustedlocations, otherlocations) <- trustPartition UnTrusted locs
        (deadlocations, safelocations) <- trustPartition DeadTrusted otherlocations
-       let present = NumCopies (length safelocations)
-       if present < numcopies
+       let present = length safelocations
+       if present < fromNumCopies numcopies
                then ifM (pure (not hasafile) <&&> checkDead key)
                        ( do
                                showLongNote $ "This key is dead, skipping."
@@ -527,21 +527,21 @@ checkKeyNumCopies key afile numcopies = do
                                untrusted <- Remote.prettyPrintUUIDs "untrusted" untrustedlocations
                                dead <- Remote.prettyPrintUUIDs "dead" deadlocations
                                warning $ missingNote desc present numcopies untrusted dead
-                               when (fromNumCopies present == 0 && not hasafile) $
+                               when (present == 0 && not hasafile) $
                                        showLongNote "(Avoid this check by running: git annex dead --key )"
                                return False
                        )
                else return True
 
-missingNote :: String -> NumCopies -> NumCopies -> String -> String -> String
-missingNote file (NumCopies 0) _ [] dead = 
+missingNote :: String -> Int -> NumCopies -> String -> String -> String
+missingNote file 0 _ [] dead = 
                "** No known copies exist of " ++ file ++ honorDead dead
-missingNote file (NumCopies 0) _ untrusted dead =
+missingNote file 0 _ untrusted dead =
                "Only these untrusted locations may have copies of " ++ file ++
                "\n" ++ untrusted ++
                "Back it up to trusted locations with git-annex copy." ++ honorDead dead
 missingNote file present needed [] _ =
-               "Only " ++ show (fromNumCopies present) ++ " of " ++ show (fromNumCopies needed) ++ 
+               "Only " ++ show present ++ " of " ++ show (fromNumCopies needed) ++ 
                " trustworthy copies exist of " ++ file ++
                "\nBack it up with git-annex copy."
 missingNote file present needed untrusted dead = 

diff --git a/Command/MinCopies.hs b/Command/MinCopies.hs
index f8678073f372a4fe2301617b6fd75b0b73e73da3..37c20ce7e43f68cc4daa8c065db505e907ae8af6 100644 (file)
--- a/Command/MinCopies.hs
+++ b/Command/MinCopies.hs
@@ -32,7 +32,7 @@ startGet = startingCustomOutput (ActionItemOther Nothing) $ next $ do
 
 startSet :: Int -> CommandStart
 startSet n = startingUsualMessages "mincopies" ai si $ do
-       setGlobalMinCopies $ MinCopies n
+       setGlobalMinCopies $ configuredMinCopies n
        next $ return True
   where
        ai = ActionItemOther (Just $ show n)

diff --git a/Command/NumCopies.hs b/Command/NumCopies.hs
index 66a6d363bc58b8e972487b86de830a4bb9da4112..86a4d956dad96cba8a1531e3ffb72f2020ae4445 100644 (file)
--- a/Command/NumCopies.hs
+++ b/Command/NumCopies.hs
@@ -8,7 +8,6 @@
 module Command.NumCopies where
 
 import Command
-import qualified Annex
 import Annex.NumCopies
 
 cmd :: Command
@@ -28,11 +27,8 @@ start' setting _ startset [s] = case readish s of
        Nothing -> giveup $ "Bad number: " ++ s
        Just n
                | n > 0 -> startset n
-               | n == 0 -> ifM (Annex.getState Annex.force)
-                       ( startset n
-                       , giveup $ "Setting " ++ setting ++ " to 0 is very unsafe. You will lose data! If you really want to do that, specify --force."
-                       )
-               | otherwise -> giveup "Number cannot be negative!"
+               | n == 0 -> giveup $ "Cannot set " ++ setting ++ " to 0."
+               | otherwise -> giveup $ setting ++ " cannot be negative!"
 start' _ _ _ _ = giveup "Specify a single number."
 
 startGet :: CommandStart
@@ -50,7 +46,7 @@ startGet = startingCustomOutput (ActionItemOther Nothing) $ next $ do
 
 startSet :: Int -> CommandStart
 startSet n = startingUsualMessages "numcopies" ai si $ do
-       setGlobalNumCopies $ NumCopies n
+       setGlobalNumCopies $ configuredNumCopies n
        next $ return True
   where
        ai = ActionItemOther (Just $ show n)

diff --git a/Command/Vicfg.hs b/Command/Vicfg.hs
index 323ed222410df463a5244bd0db3f81fd5d03ba3c..3d2d2863911d9684d4ee1f9b39e1a4a5a36c3b3a 100644 (file)
--- a/Command/Vicfg.hs
+++ b/Command/Vicfg.hs
@@ -315,7 +315,7 @@ parseCfg defcfg = go [] defcfg . lines
                        in Right $ cfg { cfgGlobalConfigs = m }
                | setting == "numcopies" = case readish val of
                        Nothing -> Left "parse error (expected an integer)"
-                       Just n -> Right $ cfg { cfgNumCopies = Just (NumCopies n) }
+                       Just n -> Right $ cfg { cfgNumCopies = Just (configuredNumCopies n) }
                | otherwise = badval "setting" setting
          where
                u = toUUID f

diff --git a/Limit.hs b/Limit.hs
index f9a0cf10d47e7e81cb8e56f9058ea9f1666c2b44..4befe8518ead77c4ec6c55c040b7eac7a4acb0c0 100644 (file)
--- a/Limit.hs
+++ b/Limit.hs
@@ -397,7 +397,7 @@ limitLackingCopies approx want = case readish want of
        Nothing -> Left "bad value for number of lacking copies"
   where
        go mi needed notpresent key = do
-               NumCopies numcopies <- if approx
+               numcopies <- if approx
                        then approxNumCopies
                        else case mi of
                                MatchingFile fi -> getGlobalFileNumCopies $
@@ -406,7 +406,7 @@ limitLackingCopies approx want = case readish want of
                                MatchingUserInfo {} -> approxNumCopies
                us <- filter (`S.notMember` notpresent)
                        <$> (trustExclude UnTrusted =<< Remote.keyLocations key)
-               return $ numcopies - length us >= needed
+               return $ fromNumCopies numcopies - length us >= needed
        approxNumCopies = fromMaybe defaultNumCopies <$> getGlobalNumCopies
 
 {- Match keys that are unused.

diff --git a/Logs/NumCopies.hs b/Logs/NumCopies.hs
index 19a1fe9c72b659fd4584980820e2228d6e7317ee..3c358819bb13d74397141964f3ba3281db7a4de6 100644 (file)
--- a/Logs/NumCopies.hs
+++ b/Logs/NumCopies.hs
@@ -24,12 +24,12 @@ import Logs
 import Logs.SingleValue
 
 instance SingleValueSerializable NumCopies where
-       serialize (NumCopies n) = encodeBS (show n)
-       deserialize = NumCopies <$$> readish . decodeBS
+       serialize = encodeBS . show . fromNumCopies
+       deserialize = configuredNumCopies <$$> readish . decodeBS
 
 instance SingleValueSerializable MinCopies where
-       serialize (MinCopies n) = encodeBS (show n)
-       deserialize = MinCopies <$$> readish . decodeBS
+       serialize = encodeBS . show . fromMinCopies
+       deserialize = configuredMinCopies <$$> readish . decodeBS
 
 setGlobalNumCopies :: NumCopies -> Annex ()
 setGlobalNumCopies new = do

diff --git a/Types/GitConfig.hs b/Types/GitConfig.hs
index d54514fc0803cea9396c3bb1f64443a4288f46e9..097a015c312890de01ed39efc887ed062b5479bd 100644 (file)
--- a/Types/GitConfig.hs
+++ b/Types/GitConfig.hs
@@ -148,7 +148,8 @@ extractGitConfig :: ConfigSource -> Git.Repo -> GitConfig
 extractGitConfig configsource r = GitConfig
        { annexVersion = RepoVersion <$> getmayberead (annexConfig "version")
        , annexUUID = hereuuid
-       , annexNumCopies = NumCopies <$> getmayberead (annexConfig "numcopies")
+       , annexNumCopies = configuredNumCopies
+               <$> getmayberead (annexConfig "numcopies")
        , annexDiskReserve = fromMaybe onemegabyte $
                readSize dataUnits =<< getmaybe (annexConfig "diskreserve")
        , annexDirect = getbool (annexConfig "direct") False

diff --git a/Types/NumCopies.hs b/Types/NumCopies.hs
index e98a614f4546d144982c44524bbc9a60d19d484a..affb91b2d6df6a3889b67e9d37f1c5f816c5827c 100644 (file)
--- a/Types/NumCopies.hs
+++ b/Types/NumCopies.hs
@@ -1,14 +1,16 @@
 {- git-annex numcopies types
  -
- - Copyright 2014-2021 Joey Hess <id@joeyh.name>
+ - Copyright 2014-2022 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU AGPL version 3 or higher.
  -}
 
 module Types.NumCopies (
-       NumCopies(..),
+       NumCopies,
+       configuredNumCopies,
        fromNumCopies,
-       MinCopies(..),
+       MinCopies,
+       configuredMinCopies,
        fromMinCopies,
        VerifiedCopy(..),
        checkVerifiedCopy,
@@ -38,12 +40,24 @@ import Control.Monad
 newtype NumCopies = NumCopies Int
        deriving (Ord, Eq, Show)
 
+-- Smart constructor; prevent configuring numcopies to 0 which would
+-- cause data loss.
+configuredNumCopies :: Int -> NumCopies
+configuredNumCopies n
+       | n > 0 = NumCopies n
+       | otherwise = NumCopies 1
+
 fromNumCopies :: NumCopies -> Int
 fromNumCopies (NumCopies n) = n
 
 newtype MinCopies = MinCopies Int
        deriving (Ord, Eq, Show)
 
+configuredMinCopies :: Int -> MinCopies
+configuredMinCopies n
+       | n > 0 = MinCopies n
+       | otherwise = MinCopies 1
+
 fromMinCopies :: MinCopies -> Int
 fromMinCopies (MinCopies n) = n
 

diff --git a/doc/git-annex-common-options.mdwn b/doc/git-annex-common-options.mdwn
index 7b8efed2bd48d8d966b24f90878994288251b162..017d85f7b47285b99b81bea20b6e38aa3f58db17 100644 (file)
--- a/doc/git-annex-common-options.mdwn
+++ b/doc/git-annex-common-options.mdwn
@@ -59,14 +59,10 @@ Most of these options are accepted by all git-annex commands.
 
   Overrides the numcopies setting.
 
-  Note that setting numcopies to 0 is very unsafe.
-
 * `--mincopies=n`
 
   Overrides the mincopies setting.
 
-  Note that setting mincopies to 0 is very unsafe.
-
 * `--time-limit=time`
 
   Limits how long a git-annex command runs. The time can be something

diff --git a/doc/git-annex.mdwn b/doc/git-annex.mdwn
index c77adc71a8ea617b3802c4bf46eb99e06e5d7388..cbaa52d2236c58ee76ebe1db4486303ad858fe74 100644 (file)
--- a/doc/git-annex.mdwn
+++ b/doc/git-annex.mdwn
@@ -932,8 +932,6 @@ repository, using [[git-annex-config]]. See its man page for a list.)
   never been configured, and when there's no annex.numcopies setting in the
   .gitattributes file.
 
-  Note that setting numcopies to 0 is very unsafe.
-
 * `annex.genmetadata`
 
   Set this to `true` to make git-annex automatically generate some metadata
@@ -1881,8 +1879,6 @@ for flac files:
        *.wav annex.numcopies=2
        *.flac annex.numcopies=3
 
-Note that setting numcopies or mincopies to 0 is very unsafe.
-
 These settings are honored by git-annex whenever it's operating on a
 matching file. However, when using --all, --unused, or --key to specify
 keys to operate on, git-annex is operating on keys and not files, so will