git-annex/Command/FromKey.hs
Joey Hess 94fcd0cf59 add routes to pause/start/cancel transfers
This commit includes a paydown on technical debt incurred two years ago,
when I didn't know that it was bad to make custom Read and Show instances
for types. As the routes need Read and Show for Transfer, which includes a
Key, and deriving my own Read instance of key was not practical,
I had to finally clean that up.

So the compact Key read and show functions are now file2key and key2file,
and Read and Show are now derived instances.

Changed all code that used the old instances, compiler checked.
(There were a few places, particularly in Command.Unused, and the test
suite where the Show instance continue to be used for legitimate
comparisons; ie show key_x == show key_y (though really in a bloom filter))
2012-08-08 16:20:24 -04:00

43 lines
1.1 KiB
Haskell

{- git-annex command
-
- Copyright 2010 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.FromKey where
import Common.Annex
import Command
import qualified Annex.Queue
import Annex.Content
import Types.Key
def :: [Command]
def = [command "fromkey" (paramPair paramKey paramPath) seek
"adds a file using a specific key"]
seek :: [CommandSeek]
seek = [withWords start]
start :: [String] -> CommandStart
start (keyname:file:[]) = notBareRepo $ do
let key = fromMaybe (error "bad key") $ file2key keyname
inbackend <- inAnnex key
unless inbackend $ error $
"key ("++ keyname ++") is not present in backend"
showStart "fromkey" file
next $ perform key file
start _ = error "specify a key and a dest file"
perform :: Key -> FilePath -> CommandPerform
perform key file = do
link <- calcGitLink file key
liftIO $ createDirectoryIfMissing True (parentDir file)
liftIO $ createSymbolicLink link file
next $ cleanup file
cleanup :: FilePath -> CommandCleanup
cleanup file = do
Annex.Queue.addCommand "add" [Param "--"] [file]
return True