git-annex/Remote/Hook.hs
2019-02-20 16:59:04 -04:00

160 lines
4.8 KiB
Haskell

{- A remote that provides hooks to run shell commands.
-
- Copyright 2011 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Remote.Hook (remote) where
import Annex.Common
import Types.Remote
import Types.Creds
import qualified Git
import Config
import Config.Cost
import Annex.UUID
import Remote.Helper.Special
import Remote.Helper.Messages
import Remote.Helper.ExportImport
import Utility.Env
import Messages.Progress
import qualified Data.Map as M
type Action = String
type HookName = String
remote :: RemoteType
remote = RemoteType
{ typename = "hook"
, enumerate = const (findSpecialRemotes "hooktype")
, generate = gen
, setup = hookSetup
, exportSupported = exportUnsupported
, importSupported = importUnsupported
}
gen :: Git.Repo -> UUID -> RemoteConfig -> RemoteGitConfig -> Annex (Maybe Remote)
gen r u c gc = do
cst <- remoteCost gc expensiveRemoteCost
return $ Just $ specialRemote c
(simplyPrepare $ store hooktype)
(simplyPrepare $ retrieve hooktype)
(simplyPrepare $ remove hooktype)
(simplyPrepare $ checkKey r hooktype)
Remote
{ uuid = u
, cost = cst
, name = Git.repoDescribe r
, storeKey = storeKeyDummy
, retrieveKeyFile = retreiveKeyFileDummy
, retrieveKeyFileCheap = retrieveCheap hooktype
-- A hook could use http and be vulnerable to
-- redirect to file:// attacks, etc.
, retrievalSecurityPolicy = mkRetrievalVerifiableKeysSecure gc
, removeKey = removeKeyDummy
, lockContent = Nothing
, checkPresent = checkPresentDummy
, checkPresentCheap = False
, exportActions = exportUnsupported
, importActions = importUnsupported
, whereisKey = Nothing
, remoteFsck = Nothing
, repairRepo = Nothing
, config = c
, localpath = Nothing
, getRepo = return r
, gitconfig = gc
, readonly = False
, appendonly = False
, availability = GloballyAvailable
, remotetype = remote
, mkUnavailable = gen r u c $
gc { remoteAnnexHookType = Just "!dne!" }
, getInfo = return [("hooktype", hooktype)]
, claimUrl = Nothing
, checkUrl = Nothing
}
where
hooktype = fromMaybe (giveup "missing hooktype") $ remoteAnnexHookType gc
hookSetup :: SetupStage -> Maybe UUID -> Maybe CredPair -> RemoteConfig -> RemoteGitConfig -> Annex (RemoteConfig, UUID)
hookSetup _ mu _ c gc = do
u <- maybe (liftIO genUUID) return mu
let hooktype = fromMaybe (giveup "Specify hooktype=") $
M.lookup "hooktype" c
(c', _encsetup) <- encryptionSetup c gc
gitConfigSpecialRemote u c' [("hooktype", hooktype)]
return (c', u)
hookEnv :: Action -> Key -> Maybe FilePath -> IO (Maybe [(String, String)])
hookEnv action k f = Just <$> mergeenv (fileenv f ++ keyenv)
where
mergeenv l = addEntries l <$> getEnvironment
envvar s v = ("ANNEX_" ++ s, v)
keyenv = catMaybes
[ Just $ envvar "KEY" (serializeKey k)
, Just $ envvar "ACTION" action
, envvar "HASH_1" <$> headMaybe hashbits
, envvar "HASH_2" <$> headMaybe (drop 1 hashbits)
]
fileenv Nothing = []
fileenv (Just file) = [envvar "FILE" file]
hashbits = map takeDirectory $ splitPath $ hashDirMixed def k
lookupHook :: HookName -> Action -> Annex (Maybe String)
lookupHook hookname action = do
command <- getConfig (annexConfig hook) ""
if null command
then do
fallback <- getConfig (annexConfig hookfallback) ""
if null fallback
then do
warning $ "missing configuration for " ++ hook ++ " or " ++ hookfallback
return Nothing
else return $ Just fallback
else return $ Just command
where
hook = hookname ++ "-" ++ action ++ "-hook"
hookfallback = hookname ++ "-hook"
runHook :: HookName -> Action -> Key -> Maybe FilePath -> Annex Bool -> Annex Bool
runHook hook action k f a = maybe (return False) run =<< lookupHook hook action
where
run command = do
showOutput -- make way for hook output
ifM (progressCommandEnv "sh" [Param "-c", Param command] =<< liftIO (hookEnv action k f))
( a
, do
warning $ hook ++ " hook exited nonzero!"
return False
)
store :: HookName -> Storer
store h = fileStorer $ \k src _p ->
runHook h "store" k (Just src) $ return True
retrieve :: HookName -> Retriever
retrieve h = fileRetriever $ \d k _p ->
unlessM (runHook h "retrieve" k (Just d) $ return True) $
giveup "failed to retrieve content"
retrieveCheap :: HookName -> Key -> AssociatedFile -> FilePath -> Annex Bool
retrieveCheap _ _ _ _ = return False
remove :: HookName -> Remover
remove h k = runHook h "remove" k Nothing $ return True
checkKey :: Git.Repo -> HookName -> CheckPresent
checkKey r h k = do
showChecking r
v <- lookupHook h action
liftIO $ check v
where
action = "checkpresent"
findkey s = serializeKey k `elem` lines s
check Nothing = giveup $ action ++ " hook misconfigured"
check (Just hook) = do
environ <- hookEnv action k Nothing
findkey <$> readProcessEnv "sh" ["-c", hook] environ