Fix mangling of --json output of utf-8 characters when not running in a utf-8 locale

As long as all code imports Utility.Aeson rather than Data.Aeson,
and no Strings that may contain utf-8 characters are used for eg, object
keys via T.pack, this is guaranteed to fix the problem everywhere that
git-annex generates json.

It's kind of annoying to need to wrap ToJSON with a ToJSON', especially
since every data type that has a ToJSON instance has to be ported over.
However, that only took 50 lines of code, which is worth it to ensure full
coverage. I initially tried an alternative approach of a newtype FileEncoded,
which had to be used everywhere a String was fed into aeson, and chasing
down all the sites would have been far too hard. Did consider creating an
intentionally overlapping instance ToJSON String, and letting ghc fail
to build anything that passed in a String, but am not sure that wouldn't
pollute some library that git-annex depends on that happens to use ToJSON
String internally.

This commit was supported by the NSF-funded DataLad project.
This commit is contained in:
Joey Hess 2018-04-16 15:42:45 -04:00
parent 6ddd374935
commit 89e1a05a8f
No known key found for this signature in database
GPG key ID: DB12DB0FF05F8F38
14 changed files with 173 additions and 62 deletions

6
Key.hs
View file

@ -22,7 +22,6 @@ module Key (
prop_isomorphic_key_decode
) where
import Data.Aeson
import Data.Char
import qualified Data.Text as T
@ -30,6 +29,7 @@ import Common
import Types.Key
import Utility.QuickCheck
import Utility.Bloom
import Utility.Aeson
import qualified Utility.SimpleProtocol as Proto
stubKey :: Key
@ -155,8 +155,8 @@ instance Hashable Key where
hashIO32 = hashIO32 . key2file
hashIO64 = hashIO64 . key2file
instance ToJSON Key where
toJSON = toJSON . key2file
instance ToJSON' Key where
toJSON' = toJSON' . key2file
instance FromJSON Key where
parseJSON (String t) = maybe mempty pure $ file2key $ T.unpack t