git-annex/Command/Mirror.hs
Joey Hess 0f921307e7 mirror: New command, makes two repositories contain the same set of files.
This is a simple approach for setting up a mirroring repository.

It will work with any type of remotes.

Mirror --from is more expensive than mirror --to in general.
OTOH, mirror --from will get the file from any remote that has it, not only
the named mirror remote. And if the named mirror remote is not the fastest
available remote with a file, that can speed things up.

It would be possible to make the assistant or watch command do a more
dynamic mirroring, that didn't need to scan every time.
2013-08-20 15:46:35 -04:00

58 lines
1.6 KiB
Haskell

{- git-annex command
-
- Copyright 2013 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.Mirror where
import Common.Annex
import Command
import GitAnnex.Options
import qualified Command.Move
import qualified Command.Drop
import qualified Command.Get
import qualified Remote
import Annex.Content
import qualified Annex
def :: [Command]
def = [withOptions fromToOptions $ command "mirror" paramPaths seek
SectionCommon "mirror content of files to/from another repository"]
seek :: [CommandSeek]
seek =
[ withField toOption Remote.byNameWithUUID $ \to ->
withField fromOption Remote.byNameWithUUID $ \from ->
withFilesInGit $ whenAnnexed $ start to from
]
start :: Maybe Remote -> Maybe Remote -> FilePath -> (Key, Backend) -> CommandStart
start to from file (key, _backend) = do
noAuto
case (from, to) of
(Nothing, Nothing) -> error "specify either --from or --to"
(Nothing, Just r) -> mirrorto r
(Just r, Nothing) -> mirrorfrom r
_ -> error "only one of --from or --to can be specified"
where
noAuto = whenM (Annex.getState Annex.auto) $
error "--auto is not supported for mirror"
mirrorto r = ifM (inAnnex key)
( Command.Move.toStart r False (Just file) key
, do
numcopies <- numCopies file
Command.Drop.startRemote file numcopies key r
)
mirrorfrom r = do
haskey <- Remote.hasKey r key
case haskey of
Left _ -> stop
Right True -> Command.Get.start' (return True) Nothing key (Just file)
Right False -> ifM (inAnnex key)
( do
numcopies <- numCopies file
Command.Drop.startLocal file numcopies key Nothing
, stop
)