git-annex/RemoteDaemon/Types.hs
Joey Hess e152c322f8
refactor ref change watching
Added to change notification to P2P protocol.

Switched to a TBChan so that a single long-running thread can be
started, and serve perhaps intermittent requests for change
notifications, without buffering all changes in memory.

The P2P runner currently starts up a new thread each times it waits
for a change, but that should allow later reusing a thread. Although
each connection from a peer will still need a new watcher thread to run.

The dependency on stm-chans is more or less free; some stuff in yesod
uses it, so it was already indirectly pulled in when building with the
webapp.

This commit was sponsored by Francois Marier on Patreon.
2016-12-09 15:01:09 -04:00

107 lines
3.2 KiB
Haskell

{- git-remote-daemon data types.
-
- Copyright 2014 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module RemoteDaemon.Types where
import Common
import qualified Annex
import qualified Git.Types as Git
import qualified Utility.SimpleProtocol as Proto
import Types.GitConfig
import Annex.ChangedRefs (ChangedRefs)
import Network.URI
import Control.Concurrent
import Control.Concurrent.STM
-- The URI of a remote is used to uniquely identify it (names change..)
newtype RemoteURI = RemoteURI URI
deriving (Show)
-- A Transport for a particular git remote consumes some messages
-- from a Chan, and emits others to another Chan.
type Transport = RemoteRepo -> RemoteURI -> TransportHandle -> TChan Consumed -> TChan Emitted -> IO ()
data RemoteRepo = RemoteRepo Git.Repo RemoteGitConfig
newtype LocalRepo = LocalRepo Git.Repo
-- All Transports share a single AnnexState MVar
--
-- Different TransportHandles may have different versions of the LocalRepo.
-- (For example, the ssh transport modifies it to enable ssh connection
-- caching.)
data TransportHandle = TransportHandle LocalRepo (MVar Annex.AnnexState)
-- Messages that the daemon emits.
data Emitted
= CONNECTED RemoteURI
| DISCONNECTED RemoteURI
| SYNCING RemoteURI
| DONESYNCING RemoteURI Bool
| WARNING RemoteURI String
deriving (Show)
-- Messages that the deamon consumes.
data Consumed
= PAUSE
| LOSTNET
| RESUME
| CHANGED ChangedRefs
| RELOAD
| STOP
deriving (Show)
instance Proto.Sendable Emitted where
formatMessage (CONNECTED remote) =
["CONNECTED", Proto.serialize remote]
formatMessage (DISCONNECTED remote) =
["DISCONNECTED", Proto.serialize remote]
formatMessage (SYNCING remote) =
["SYNCING", Proto.serialize remote]
formatMessage (DONESYNCING remote status) =
["DONESYNCING", Proto.serialize remote, Proto.serialize status]
formatMessage (WARNING remote message) =
["WARNING", Proto.serialize remote, Proto.serialize message]
instance Proto.Sendable Consumed where
formatMessage PAUSE = ["PAUSE"]
formatMessage LOSTNET = ["LOSTNET"]
formatMessage RESUME = ["RESUME"]
formatMessage (CHANGED refs) =["CHANGED", Proto.serialize refs]
formatMessage RELOAD = ["RELOAD"]
formatMessage STOP = ["STOP"]
instance Proto.Receivable Emitted where
parseCommand "CONNECTED" = Proto.parse1 CONNECTED
parseCommand "DISCONNECTED" = Proto.parse1 DISCONNECTED
parseCommand "SYNCING" = Proto.parse1 SYNCING
parseCommand "DONESYNCING" = Proto.parse2 DONESYNCING
parseCommand "WARNING" = Proto.parse2 WARNING
parseCommand _ = Proto.parseFail
instance Proto.Receivable Consumed where
parseCommand "PAUSE" = Proto.parse0 PAUSE
parseCommand "LOSTNET" = Proto.parse0 LOSTNET
parseCommand "RESUME" = Proto.parse0 RESUME
parseCommand "CHANGED" = Proto.parse1 CHANGED
parseCommand "RELOAD" = Proto.parse0 RELOAD
parseCommand "STOP" = Proto.parse0 STOP
parseCommand _ = Proto.parseFail
instance Proto.Serializable RemoteURI where
serialize (RemoteURI u) = show u
deserialize = RemoteURI <$$> parseURI
instance Proto.Serializable Bool where
serialize False = "0"
serialize True = "1"
deserialize "0" = Just False
deserialize "1" = Just True
deserialize _ = Nothing