git-annex/CmdLine/Batch.hs
Joey Hess 3a05d53761
add SeekInput (not yet used)
No behavior changes (hopefully), just adding SeekInput and plumbing it
through to the JSON display code for later use.

Over the course of 2 grueling days.

withFilesNotInGit reimplemented in terms of seekHelper
should be the only possible behavior change. It seems to test as
behaving the same.

Note that seekHelper dummies up the SeekInput in the case where
segmentPaths' gives up on sorting the expanded paths because there are
too many input paths. When SeekInput later gets exposed as a json field,
that will result in it being a little bit wrong in the case where
100 or more paths are passed to a git-annex command. I think this is a
subtle enough problem to not matter. If it does turn out to be a
problem, fixing it would require splitting up the input
parameters into groups of < 100, which would make git ls-files run
perhaps more than is necessary. May want to revisit this, because that
fix seems fairly low-impact.
2020-09-15 15:41:13 -04:00

135 lines
4.3 KiB
Haskell

{- git-annex batch commands
-
- Copyright 2015-2020 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module CmdLine.Batch where
import Annex.Common
import Types.Command
import CmdLine.Action
import CmdLine.GitAnnex.Options
import CmdLine.Seek
import Options.Applicative
import Limit
import Types.FileMatcher
import Annex.BranchState
import Annex.WorkTree
import Annex.Content
data BatchMode = Batch BatchFormat | NoBatch
data BatchFormat = BatchLine | BatchNull
parseBatchOption :: Parser BatchMode
parseBatchOption = go
<$> switch
( long "batch"
<> help "enable batch mode"
)
<*> switch
( short 'z'
<> help "null delimited batch input"
)
where
go True False = Batch BatchLine
go True True = Batch BatchNull
go False _ = NoBatch
-- A batchable command can run in batch mode, or not.
-- In batch mode, one line at a time is read, parsed, and a reply output to
-- stdout. In non batch mode, the command's parameters are parsed and
-- a reply output for each.
batchable :: (opts -> SeekInput -> String -> Annex Bool) -> Parser opts -> CmdParamsDesc -> CommandParser
batchable handler parser paramdesc = batchseeker <$> batchparser
where
batchparser = (,,)
<$> parser
<*> parseBatchOption
<*> cmdParams paramdesc
batchseeker (opts, NoBatch, params) =
mapM_ (\p -> go NoBatch opts (SeekInput [p], p)) params
batchseeker (opts, batchmode@(Batch fmt), _) =
batchInput fmt (pure . Right) (go batchmode opts)
go batchmode opts (si, p) =
unlessM (handler opts si p) $
batchBadInput batchmode
-- bad input is indicated by an empty line in batch mode. In non batch
-- mode, exit on bad input.
batchBadInput :: BatchMode -> Annex ()
batchBadInput NoBatch = liftIO exitFailure
batchBadInput (Batch _) = liftIO $ putStrLn ""
-- Reads lines of batch mode input, runs a parser, and passes the result
-- to the action.
--
-- Note that if the batch input includes a worktree filename, it should
-- be converted to relative. Normally, filename parameters are passed
-- through git ls-files, which makes them relative, but batch mode does
-- not use that, and absolute worktree files are likely to cause breakage.
batchInput :: BatchFormat -> (String -> Annex (Either String v)) -> ((SeekInput, v) -> Annex ()) -> Annex ()
batchInput fmt parser a = go =<< batchLines fmt
where
go [] = return ()
go (l:rest) = do
either parseerr (\v -> a (SeekInput [l], v)) =<< parser l
go rest
parseerr s = giveup $ "Batch input parse failure: " ++ s
batchLines :: BatchFormat -> Annex [String]
batchLines fmt = do
enableInteractiveBranchAccess
liftIO $ splitter <$> getContents
where
splitter = case fmt of
BatchLine -> lines
BatchNull -> splitc '\0'
-- Runs a CommandStart in batch mode.
--
-- The batch mode user expects to read a line of output, and it's up to the
-- CommandStart to generate that output as it succeeds or fails to do its
-- job. However, if it stops without doing anything, it won't generate
-- any output, so in that case, batchBadInput is used to provide the caller
-- with an empty line.
batchCommandAction :: CommandStart -> Annex ()
batchCommandAction a = maybe (batchBadInput (Batch BatchLine)) (const noop)
=<< callCommandAction' a
-- Reads lines of batch input and passes the filepaths to a CommandStart
-- to handle them.
--
-- Absolute filepaths are converted to relative.
--
-- File matching options are not checked.
batchStart :: BatchFormat -> (SeekInput -> FilePath -> CommandStart) -> Annex ()
batchStart fmt a = batchInput fmt (Right <$$> liftIO . relPathCwdToFile) $
batchCommandAction . uncurry a
-- Like batchStart, but checks the file matching options
-- and skips non-matching files.
batchFilesMatching :: BatchFormat -> ((SeekInput, RawFilePath) -> CommandStart) -> Annex ()
batchFilesMatching fmt a = do
matcher <- getMatcher
batchStart fmt $ \si f ->
let f' = toRawFilePath f
in ifM (matcher $ MatchingFile $ FileInfo f' f')
( a (si, f')
, return Nothing
)
batchAnnexedFilesMatching :: BatchFormat -> AnnexedFileSeeker -> Annex ()
batchAnnexedFilesMatching fmt seeker = batchFilesMatching fmt $ \(si, bf) ->
flip whenAnnexed bf $ \f k ->
case checkContentPresent seeker of
Just v -> do
present <- inAnnex k
if present == v
then startAction seeker si f k
else return Nothing
Nothing -> startAction seeker si f k