rest-stringmap-0.2: src/Rest/StringMap/Util.hs

module Rest.StringMap.Util
  ( pickleStringMap
  , pickleMap
  , mapSchema
  ) where

import Data.JSON.Schema (JSONSchema, Schema, schema)
import Data.JSON.Schema.Combinators (field)
import Data.Proxy (Proxy)
import Data.String (IsString (..))
import Data.String.ToString (ToString (..))
import Text.XML.HXT.Arrow.Pickle (PU, XmlPickler, xpElem, xpList, xpPair, xpTextAttr, xpWrap, xpickle)

pickleStringMap :: XmlPickler b => ([(String, b)] -> m) -> (m -> [(String, b)]) -> PU m
pickleStringMap fromList toList =
  xpElem "map"
    $ xpWrap (fromList, toList)
    $ xpList (xpElem "value" (xpPair (xpTextAttr "key") xpickle))

pickleMap :: (XmlPickler m, ToString k, IsString k) => ((String -> k) -> m -> m') -> ((k -> String) -> m' -> m) -> PU m'
pickleMap mapKeys mapKeys' = xpWrap (mapKeys fromString, mapKeys' toString) xpickle

mapSchema :: JSONSchema a => Proxy a -> Schema
mapSchema = field "key" False . schema