git-annex/Assistant/Monad.hs
Joey Hess aaba83795b
switch from hslogger to purpose-built Utility.Debug
This uses a DebugSelector, rather than debug levels, which will allow
for a later option like --debug-from=Process to only
see debuging about running processes.

The module name that contains the thing being debugged is used as the
DebugSelector (in most cases; does not need to be a hard and fast rule).
Debug calls were changed to add that. hslogger did not display
that first parameter to debugM, but the DebugSelector does get
displayed.

Also fastDebug will allow doing debugging in places that are used in
tight loops, with the DebugSelector coming from the Annex Reader
essentially for free. Not done yet.
2021-04-05 13:40:31 -04:00

143 lines
3.8 KiB
Haskell

{- git-annex assistant monad
-
- Copyright 2012 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE GeneralizedNewtypeDeriving, MultiParamTypeClasses #-}
module Assistant.Monad (
Assistant,
AssistantData(..),
newAssistantData,
runAssistant,
getAssistant,
LiftAnnex,
liftAnnex,
(<~>),
(<<~),
asIO,
asIO1,
asIO2,
ThreadName,
debug,
) where
import "mtl" Control.Monad.Reader
import qualified Control.Monad.Fail as Fail
import Annex.Common
import Assistant.Types.ThreadedMonad
import Assistant.Types.DaemonStatus
import Assistant.Types.ScanRemotes
import Assistant.Types.TransferQueue
import Assistant.Types.TransferSlots
import Assistant.Types.Pushes
import Assistant.Types.BranchChange
import Assistant.Types.Commits
import Assistant.Types.Changes
import Assistant.Types.RepoProblem
import Assistant.Types.ThreadName
import Assistant.Types.RemoteControl
import Assistant.Types.CredPairCache
import qualified Utility.Debug as Debug
newtype Assistant a = Assistant { mkAssistant :: ReaderT AssistantData IO a }
deriving (
Monad,
MonadIO,
MonadReader AssistantData,
MonadCatch,
MonadThrow,
MonadMask,
Fail.MonadFail,
Functor,
Applicative
)
data AssistantData = AssistantData
{ threadName :: ThreadName
, threadState :: ThreadState
, daemonStatusHandle :: DaemonStatusHandle
, scanRemoteMap :: ScanRemoteMap
, transferQueue :: TransferQueue
, transferSlots :: TransferSlots
, failedPushMap :: FailedPushMap
, failedExportMap :: FailedPushMap
, commitChan :: CommitChan
, exportCommitChan :: CommitChan
, changePool :: ChangePool
, repoProblemChan :: RepoProblemChan
, branchChangeHandle :: BranchChangeHandle
, remoteControl :: RemoteControl
, credPairCache :: CredPairCache
}
newAssistantData :: ThreadState -> DaemonStatusHandle -> IO AssistantData
newAssistantData st dstatus = AssistantData
<$> pure (ThreadName "main")
<*> pure st
<*> pure dstatus
<*> newScanRemoteMap
<*> newTransferQueue
<*> newTransferSlots
<*> newFailedPushMap
<*> newFailedPushMap
<*> newCommitChan
<*> newCommitChan
<*> newChangePool
<*> newRepoProblemChan
<*> newBranchChangeHandle
<*> newRemoteControl
<*> newCredPairCache
runAssistant :: AssistantData -> Assistant a -> IO a
runAssistant d a = runReaderT (mkAssistant a) d
getAssistant :: (AssistantData -> a) -> Assistant a
getAssistant = reader
{- Using a type class for lifting into the annex monad allows
- easily lifting to it from multiple different monads. -}
class LiftAnnex m where
liftAnnex :: Annex a -> m a
{- Runs an action in the git-annex monad. Note that the same monad state
- is shared among all assistant threads, so only one of these can run at
- a time. Therefore, long-duration actions should be avoided. -}
instance LiftAnnex Assistant where
liftAnnex a = do
st <- reader threadState
liftIO $ runThreadState st a
{- Runs an IO action, passing it an IO action that runs an Assistant action. -}
(<~>) :: (IO a -> IO b) -> Assistant a -> Assistant b
io <~> a = do
d <- reader id
liftIO $ io $ runAssistant d a
{- Creates an IO action that will run an Assistant action when run. -}
asIO :: Assistant a -> Assistant (IO a)
asIO a = do
d <- reader id
return $ runAssistant d a
asIO1 :: (a -> Assistant b) -> Assistant (a -> IO b)
asIO1 a = do
d <- reader id
return $ \v -> runAssistant d $ a v
asIO2 :: (a -> b -> Assistant c) -> Assistant (a -> b -> IO c)
asIO2 a = do
d <- reader id
return $ \v1 v2 -> runAssistant d (a v1 v2)
{- Runs an IO action on a selected field of the AssistantData. -}
(<<~) :: (a -> IO b) -> (AssistantData -> a) -> Assistant b
io <<~ v = reader v >>= liftIO . io
debug :: [String] -> Assistant ()
debug ws = do
ThreadName name <- getAssistant threadName
liftIO $ Debug.debug (Debug.DebugSource (encodeBS name)) (unwords ws)