git-annex/Assistant/Threads/ConfigMonitor.hs
Joey Hess 9411a7c93c
matching preferred content before key is known
This will let import try to match preferred content expressions before
downloading the content and generating its key.

If an expression needs a key, it preferredContentParser with
preferredContentKeylessTokens will fail to parse it.

standard and groupwanted are not in preferredContentKeylessTokens
because they may refer to an expression that refers to a key.
That needs further work to support them.
2019-05-14 14:28:23 -04:00

93 lines
3 KiB
Haskell

{- git-annex assistant config monitor thread
-
- Copyright 2012 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Assistant.Threads.ConfigMonitor where
import Assistant.Common
import Assistant.BranchChange
import Assistant.DaemonStatus
import Assistant.Commits
import Utility.ThreadScheduler
import Logs
import Logs.UUID
import Logs.Trust
import Logs.PreferredContent
import Logs.Group
import Logs.NumCopies
import Remote.List (remoteListRefresh)
import qualified Git.LsTree as LsTree
import Git.Types
import Git.FilePath
import qualified Annex.Branch
import Annex.FileMatcher
import qualified Data.Set as S
{- This thread detects when configuration changes have been made to the
- git-annex branch and reloads cached configuration.
-
- If the branch is frequently changing, it's checked for configuration
- changes no more often than once every 60 seconds. On the other hand,
- if the branch has not changed in a while, configuration changes will
- be detected immediately.
-}
configMonitorThread :: NamedThread
configMonitorThread = namedThread "ConfigMonitor" $ loop =<< getConfigs
where
loop old = do
waitBranchChange
new <- getConfigs
when (old /= new) $ do
let changedconfigs = new `S.difference` old
debug $ "reloading config" :
map fst (S.toList changedconfigs)
reloadConfigs new
{- Record a commit to get this config
- change pushed out to remotes. -}
recordCommit
liftIO $ threadDelaySeconds (Seconds 60)
loop new
{- Config files, and their checksums. -}
type Configs = S.Set (FilePath, Sha)
{- All git-annex's config files, and actions to run when they change. -}
configFilesActions :: [(FilePath, Assistant ())]
configFilesActions =
[ (uuidLog, void $ liftAnnex uuidDescMapLoad)
, (remoteLog, void $ liftAnnex remoteListRefresh)
, (trustLog, void $ liftAnnex trustMapLoad)
, (groupLog, void $ liftAnnex groupMapLoad)
, (numcopiesLog, void $ liftAnnex globalNumCopiesLoad)
, (scheduleLog, void updateScheduleLog)
-- Preferred and required content settings depend on most of the
-- other configs, so will be reloaded whenever any configs change.
, (preferredContentLog, noop)
, (requiredContentLog, noop)
, (groupPreferredContentLog, noop)
]
reloadConfigs :: Configs -> Assistant ()
reloadConfigs changedconfigs = do
sequence_ as
void $ liftAnnex $ preferredRequiredMapsLoad preferredContentTokens
{- Changes to the remote log, or the trust log, can affect the
- syncRemotes list. Changes to the uuid log may affect its
- display so are also included. -}
when (any (`elem` fs) [remoteLog, trustLog, uuidLog])
updateSyncRemotes
where
(fs, as) = unzip $ filter (flip S.member changedfiles . fst)
configFilesActions
changedfiles = S.map fst changedconfigs
getConfigs :: Assistant Configs
getConfigs = S.fromList . map extract
<$> liftAnnex (inRepo $ LsTree.lsTreeFiles Annex.Branch.fullname files)
where
files = map fst configFilesActions
extract treeitem = (getTopFilePath $ LsTree.file treeitem, LsTree.sha treeitem)