git-annex/Backend/WORM.hs
Joey Hess 9c4650358c
add KeyVariety type
Where before the "name" of a key and a backend was a string, this makes
it a concrete data type.

This is groundwork for allowing some varieties of keys to be disabled
in file2key, so git-annex won't use them at all.

Benchmarks ran in my big repo:

old git-annex info:

real	0m3.338s
user	0m3.124s
sys	0m0.244s

new git-annex info:

real	0m3.216s
user	0m3.024s
sys	0m0.220s

new git-annex find:

real	0m7.138s
user	0m6.924s
sys	0m0.252s

old git-annex find:

real	0m7.433s
user	0m7.240s
sys	0m0.232s

Surprising result; I'd have expected it to be slower since it now parses
all the key varieties. But, the parser is very simple and perhaps
sharing KeyVarieties uses less memory or something like that.

This commit was supported by the NSF-funded DataLad project.
2017-02-24 15:16:56 -04:00

44 lines
1.1 KiB
Haskell

{- git-annex "WORM" backend -- Write Once, Read Many
-
- Copyright 2010 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Backend.WORM (backends) where
import Annex.Common
import Types.Key
import Types.Backend
import Types.KeySource
import Backend.Utilities
import Git.FilePath
backends :: [Backend]
backends = [backend]
backend :: Backend
backend = Backend
{ backendVariety = WORMKey
, getKey = keyValue
, verifyKeyContent = Nothing
, canUpgradeKey = Nothing
, fastMigrate = Nothing
, isStableKey = const True
}
{- The key includes the file size, modification time, and the
- original filename relative to the top of the git repository.
-}
keyValue :: KeySource -> Annex (Maybe Key)
keyValue source = do
let f = contentLocation source
stat <- liftIO $ getFileStatus f
sz <- liftIO $ getFileSize' f stat
relf <- getTopFilePath <$> inRepo (toTopFilePath $ keyFilename source)
return $ Just $ stubKey
{ keyName = genKeyName relf
, keyVariety = WORMKey
, keySize = Just sz
, keyMtime = Just $ modificationTime stat
}