src: update for changed map type in aeson-2

This means that we're now using Data.Map.Strict instead of
Data.HashMap.Strict for JSON objects in general, and specifically
for claims maps and CSV rows.

This addresses certain hash flooding vulnerabilities, but may
have performance downsides.

Compare e.g. https://frasertweedale.github.io/blog-fp/posts/2021-10-12-aeson-hash-flooding-protection.html

src/PostgREST/Request/ApiRequest.hs

@@ -18,6 +18,8 @@ module PostgREST.Request.ApiRequest
   ) where
 
 import qualified Data.Aeson            as JSON
+import qualified Data.Aeson.Key        as K
+import qualified Data.Aeson.KeyMap     as KM
 import qualified Data.ByteString.Char8 as BS
 import qualified Data.ByteString.Lazy  as LBS
 import qualified Data.CaseInsensitive  as CI
@@ -25,6 +27,7 @@ import qualified Data.Csv              as CSV
 import qualified Data.HashMap.Strict   as HM
 import qualified Data.List             as L
 import qualified Data.List.NonEmpty    as NonEmptyList
+import qualified Data.Map.Strict       as M
 import qualified Data.Set              as S
 import qualified Data.Text.Encoding    as T
 import qualified Data.Vector           as V
@@ -357,7 +360,7 @@ mutuallyAgreeable sProduces cAccepts =
      then listToMaybe sProduces
      else exact
 
-type CsvData = V.Vector (HM.HashMap Text LBS.ByteString)
+type CsvData = V.Vector (M.Map Text LBS.ByteString)
 
 {-|
   Converts CSV like
@@ -375,8 +378,8 @@ csvToJson :: (CSV.Header, CsvData) -> JSON.Value
 csvToJson (_, vals) =
   JSON.Array $ V.map rowToJsonObj vals
  where
-  rowToJsonObj = JSON.Object .
-    HM.map (\str ->
+  rowToJsonObj = JSON.Object . KM.fromMapText .
+    M.map (\str ->
         if str == "NULL"
           then JSON.Null
           else JSON.String . T.decodeUtf8 $ LBS.toStrict str
@@ -389,9 +392,9 @@ payloadAttributes raw json =
     JSON.Array arr ->
       case arr V.!? 0 of
         Just (JSON.Object o) ->
-          let canonicalKeys = S.fromList $ HM.keys o
+          let canonicalKeys = S.fromList $ K.toText <$> KM.keys o
               areKeysUniform = all (\case
-                JSON.Object x -> S.fromList (HM.keys x) == canonicalKeys
+                JSON.Object x -> S.fromList (K.toText <$> KM.keys x) == canonicalKeys
                 _ -> False) arr in
           if areKeysUniform
             then Just $ ProcessedJSON raw canonicalKeys
@@ -399,7 +402,7 @@ payloadAttributes raw json =
         Just _ -> Nothing
         Nothing -> Just emptyPJArray
 
-    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ HM.keys o)
+    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ K.toText <$> KM.keys o)
 
     -- truncate everything else to an empty array.
     _ -> Just emptyPJArray