git-annex/Assistant/Threads/Pusher.hs
2012-06-25 20:16:30 -04:00

87 lines
2.9 KiB
Haskell

{- git-annex assistant git pushing threads
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Assistant.Threads.Pusher where
import Common.Annex
import Assistant.Commits
import Assistant.Pushes
import Assistant.ThreadedMonad
import Assistant.Threads.Merger
import qualified Command.Sync
import Utility.ThreadScheduler
import Utility.Parallel
import Data.Time.Clock
{- This thread retries pushes that failed before. -}
pushRetryThread :: ThreadState -> FailedPushChan -> IO ()
pushRetryThread st pushchan = runEvery (Seconds halfhour) $ do
-- We already waited half an hour, now wait until there are failed
-- pushes to retry.
pushes <- getFailedPushes pushchan
-- Check times, to avoid repushing a push that's too new.
now <- getCurrentTime
let (newpushes, oldpushes) = partition (toorecent now . failedTimeStamp) pushes
unless (null newpushes) $
refillFailedPushes pushchan newpushes
unless (null oldpushes) $
pushToRemotes now st pushchan $ map failedRemote oldpushes
where
halfhour = 1800
toorecent now time = now `diffUTCTime` time < fromIntegral halfhour
{- This thread pushes git commits out to remotes soon after they are made. -}
pushThread :: ThreadState -> CommitChan -> FailedPushChan -> IO ()
pushThread st commitchan pushchan = do
remotes <- runThreadState st $ Command.Sync.syncRemotes []
runEvery (Seconds 2) $ do
-- We already waited two seconds as a simple rate limiter.
-- Next, wait until at least one commit has been made
commits <- getCommits commitchan
-- Now see if now's a good time to push.
now <- getCurrentTime
if shouldPush now commits
then pushToRemotes now st pushchan remotes
else refillCommits commitchan commits
{- Decide if now is a good time to push to remotes.
-
- Current strategy: Immediately push all commits. The commit machinery
- already determines batches of changes, so we can't easily determine
- batches better.
-}
shouldPush :: UTCTime -> [Commit] -> Bool
shouldPush _now commits
| not (null commits) = True
| otherwise = False
{- Updates the local sync branch, then pushes it to all remotes, in
- parallel.
-
- Avoids running possibly long-duration commands in the Annex monad, so
- as not to block other threads. -}
pushToRemotes :: UTCTime -> ThreadState -> FailedPushChan -> [Remote] -> IO ()
pushToRemotes now st pushchan remotes = do
(g, branch) <- runThreadState st $
(,) <$> fromRepo id <*> Command.Sync.currentBranch
go True branch g remotes
where
go shouldretry branch g rs = do
Command.Sync.updateBranch (Command.Sync.syncBranch branch) g
failed <- inParallel (push g branch) rs
unless (null failed) $
if shouldretry
then retry branch g rs
else refillFailedPushes pushchan $
map (`FailedPush` now) failed
push g branch remote =
ifM (Command.Sync.pushBranch remote branch g)
( exitSuccess, exitFailure)
retry branch g rs = do
runThreadState st $ manualPull branch rs
go False branch g rs