git-annex/Remote/Hook.hs
2015-01-21 12:50:09 -04:00

149 lines
4.3 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 qualified Data.Map as M
import Common.Annex
import Types.Remote
import Types.Key
import Types.Creds
import qualified Git
import Config
import Config.Cost
import Annex.UUID
import Remote.Helper.Special
import Utility.Env
type Action = String
type HookName = String
remote :: RemoteType
remote = RemoteType {
typename = "hook",
enumerate = findSpecialRemotes "hooktype",
generate = gen,
setup = hookSetup
}
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
, removeKey = removeKeyDummy
, checkPresent = checkPresentDummy
, checkPresentCheap = False
, whereisKey = Nothing
, remoteFsck = Nothing
, repairRepo = Nothing
, config = c
, localpath = Nothing
, repo = r
, gitconfig = gc
, readonly = 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 (error "missing hooktype") $ remoteAnnexHookType gc
hookSetup :: Maybe UUID -> Maybe CredPair -> RemoteConfig -> Annex (RemoteConfig, UUID)
hookSetup mu _ c = do
u <- maybe (liftIO genUUID) return mu
let hooktype = fromMaybe (error "Specify hooktype=") $
M.lookup "hooktype" c
(c', _encsetup) <- encryptionSetup c
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" (key2file 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 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 (liftIO $ boolSystemEnv "sh" [Param "-c", Param command] =<< 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) $
error "failed to retrieve content"
retrieveCheap :: HookName -> Key -> 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
showAction $ "checking " ++ Git.repoDescribe r
v <- lookupHook h action
liftIO $ check v
where
action = "checkpresent"
findkey s = key2file k `elem` lines s
check Nothing = error $ action ++ " hook misconfigured"
check (Just hook) = do
environ <- hookEnv action k Nothing
findkey <$> readProcessEnv "sh" ["-c", hook] environ