git-annex/Command/Copy.hs
Joey Hess a6c1d9752b
move/copy: option parsing for --from with --to
Allowing --from and --to as an alternative to --from or --to
is hard to do with optparse-applicative!

The obvious approach of (pfrom <|> pto <|> pfromandto) does not work
when pfromandto uses the same option names as pfrom and pto do.
It compiles but the generated parser does not work for all desired
combinations.

Instead, have to parse optionally from and optionally to. When neither
is provided, the parser succeeds, but it's a result that can't be
handled. So, have to giveup after option parsing. There does not seem to
be a way to make an optparse-applicative Parser give up internally
either.

Also, need seek' because I first tried making fto be a where binding,
but that resulted in a hang when git-annex move was run without --from
or --to. I think because startConcurrency was not expecting the stages
value to contain an exception and so ended up blocking.

Sponsored-by: Dartmouth College's DANDI project
2023-01-18 14:42:39 -04:00

95 lines
2.9 KiB
Haskell

{- git-annex command
-
- Copyright 2010-2023 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Command.Copy where
import Command
import qualified Command.Move
import qualified Remote
import Annex.Wanted
import Annex.NumCopies
cmd :: Command
cmd = withAnnexOptions [jobsOption, jsonOptions, jsonProgressOption, annexedMatchingOptions] $
command "copy" SectionCommon
"copy content of files to/from another repository"
paramPaths (seek <--< optParser)
data CopyOptions = CopyOptions
{ copyFiles :: CmdParams
, fromToOptions :: Maybe FromToHereOptions
, keyOptions :: Maybe KeyOptions
, autoMode :: Bool
, batchOption :: BatchMode
}
optParser :: CmdParamsDesc -> Parser CopyOptions
optParser desc = CopyOptions
<$> cmdParams desc
<*> parseFromToHereOptions
<*> optional (parseKeyOptions <|> parseFailedTransfersOption)
<*> parseAutoOption
<*> parseBatchOption True
instance DeferredParseClass CopyOptions where
finishParse v = CopyOptions
<$> pure (copyFiles v)
<*> maybe (pure Nothing) (Just <$$> finishParse)
(fromToOptions v)
<*> pure (keyOptions v)
<*> pure (autoMode v)
<*> pure (batchOption v)
seek :: CopyOptions -> CommandSeek
seek o = case fromToOptions o of
Just fto -> seek' o fto
Nothing -> giveup "Specify --from or --to"
seek' :: CopyOptions -> FromToHereOptions -> CommandSeek
seek' o fto = startConcurrency commandStages $ do
case batchOption o of
NoBatch -> withKeyOptions
(keyOptions o) (autoMode o) seeker
(commandAction . keyaction)
(withFilesInGitAnnex ww seeker)
=<< workTreeItems ww (copyFiles o)
Batch fmt -> batchOnly (keyOptions o) (copyFiles o) $
batchAnnexed fmt seeker keyaction
where
ww = WarnUnmatchLsFiles
seeker = AnnexedFileSeeker
{ startAction = start o fto
, checkContentPresent = case fto of
FromOrToRemote (FromRemote _) -> Just False
FromOrToRemote (ToRemote _) -> Just True
ToHere -> Just False
FromRemoteToRemote _ _ -> Just False
, usesLocationLog = True
}
keyaction = Command.Move.startKey fto Command.Move.RemoveNever
{- A copy is just a move that does not delete the source file.
- However, auto mode avoids unnecessary copies, and avoids getting or
- sending non-preferred content. -}
start :: CopyOptions -> FromToHereOptions -> SeekInput -> RawFilePath -> Key -> CommandStart
start o fto si file key = stopUnless shouldCopy $
Command.Move.start fto Command.Move.RemoveNever si file key
where
shouldCopy
| autoMode o = want <||> numCopiesCheck file key (<)
| otherwise = return True
want = case fto of
FromOrToRemote (ToRemote dest) ->
(Remote.uuid <$> getParsed dest) >>= checkwantsend
FromOrToRemote (FromRemote _) -> checkwantget
ToHere -> checkwantget
FromRemoteToRemote _ dest ->
(Remote.uuid <$> getParsed dest) >>= checkwantsend
checkwantsend = wantGetBy False (Just key) (AssociatedFile (Just file))
checkwantget = wantGet False (Just key) (AssociatedFile (Just file))