Data.Json.Parser

Parsing from different types

parseJsonBs :: JsonReadable t => ByteString -> Either String t

Parse json from a strict ByteString

parseJsonBsl :: JsonReadable t => ByteString -> Either String t

Parse json from a lazy ByteString

parseJsonT :: JsonReadable t => Text -> Either String t

Parse json from a strict Text

Description how to parse JSON to a Haskell type

class JsonReadable t where

Typeclass defining an attoparsec Parser how Haskell types should be parsed from JSON. Use predifined instances (with readJson) and runSpec (on ObjSpec) to define instances for custom types

Methods

readJson :: Parser t

Instances

JsonReadable Bool

JsonReadable Double

JsonReadable Int

JsonReadable Int8

JsonReadable Int16

JsonReadable Int32

JsonReadable Int64

JsonReadable Word

JsonReadable Word8

JsonReadable Word16

JsonReadable Word32

JsonReadable Word64

JsonReadable Text

JsonReadable Scientific

JsonReadable t => JsonReadable [t]

JsonReadable t => JsonReadable (Maybe t)

JsonReadable t => JsonReadable (Vector t)

(JsonReadable a, JsonReadable b) => JsonReadable (Either a b)

JsonReadable t => JsonReadable (t, t)

DSL to easily create parser for custom Haskell types

runSpec :: HVectElim ts x -> ObjSpec ts -> Parser x

Convert an ObjSpec into a Parser provided a constructor function

data ObjSpec ts where

List of TypedKeys, should be in the same order as your constructor in runSpec will expect them

Constructors

ObjSpecNil :: ObjSpec []

(:&&:) :: (JsonReadable t, Typeable t) => !(TypedKey t) -> !(ObjSpec ts) -> ObjSpec (t : ts) infixr 5

data TypedKey t

Json object key to a value t

Instances

Typeable * t => IsString (TypedKey t)

Typeable * t => IsString (TypedKey (Maybe t))

reqKey :: Typeable t => Text -> TypedKey t

Required json object key. Use IsString instance for automatic choice

optKey :: Typeable t => Text -> TypedKey (Maybe t)

Optional json object key. Use IsString instance for automatic choice

Low level JSON parsing helpers

readObject :: (Text -> Maybe (Parser WrappedValue)) -> Parser (HashMap Text WrappedValue)

Parse a json object given a value parser for each key

data WrappedValue

A value that is Typeable and JsonReadable

Constructors

forall t . (Typeable t, JsonReadable t) => WrappedValue !t

getValueByKey :: (Monad m, Typeable t) => Text -> HashMap Text WrappedValue -> m t

Get a value out of the map returned by readObject

getOptValueByKey :: (Monad m, Typeable t) => Text -> HashMap Text WrappedValue -> m (Maybe t)

Optionally get a value out of the map returned by readObject