git-annex/Logs/ContentIdentifier/Pure.hs
2019-03-06 11:59:42 -04:00

60 lines
1.7 KiB
Haskell

{- Remote content identifier logs, pure operations.
-
- Copyright 2019 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Logs.ContentIdentifier.Pure where
import Annex.Common
import Logs.UUIDBased
import Types.Import
import Utility.Base64
import qualified Data.ByteString as S
import qualified Data.ByteString.Char8 as S8
import qualified Data.ByteString.Lazy as L
import qualified Data.Attoparsec.ByteString.Lazy as A
import qualified Data.Attoparsec.ByteString.Char8 as A8
import Data.ByteString.Builder
type ContentIdentifierLog = Log [ContentIdentifier]
buildLog :: ContentIdentifierLog -> Builder
buildLog = buildLogNew buildContentIdentifierList
buildContentIdentifierList :: [ContentIdentifier] -> Builder
buildContentIdentifierList l = case l of
[] -> mempty
[c] -> buildcid c
(c:cs) -> buildcid c <> charUtf8 ':' <> buildContentIdentifierList cs
where
buildcid (ContentIdentifier c)
| S8.any (`elem` [':', '\r', '\n']) c || "!" `S8.isPrefixOf` c =
charUtf8 '!' <> byteString (toB64' c)
| otherwise = byteString c
parseLog :: L.ByteString -> ContentIdentifierLog
parseLog = parseLogNew parseContentIdentifierList
parseContentIdentifierList :: A.Parser [ContentIdentifier]
parseContentIdentifierList = reverse . catMaybes <$> valueparser []
where
valueparser l = do
b <- A8.takeWhile (/= ':')
let cid = if "!" `S8.isPrefixOf` b
then ContentIdentifier <$> fromB64Maybe' (S.drop 1 b)
else Just $ ContentIdentifier b
ifM A8.atEnd
( return (cid:l)
, do
_ <- A8.char ':'
valueparser (cid:l)
)
prop_parse_build_contentidentifier_log :: ContentIdentifierLog -> Bool
prop_parse_build_contentidentifier_log l =
parseLog (toLazyByteString (buildLog l)) == l