graphql/tests/Test/StarWars/Schema.hs
Danny Navarro 8ee50727bd Overhaul Schema DSL
Aside of making the definition of Schemas easier, it takes care of
issues like nested aliases which previously wasn't possible. The naming
of the DSL functions is still provisional.
2016-02-18 13:49:02 +01:00

56 lines
1.8 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Test.StarWars.Schema where
import Control.Applicative ((<|>), Alternative, empty)
import Data.GraphQL.Schema
import Test.StarWars.Data
-- * Schema
-- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsSchema.js
schema :: (Alternative m, Monad m) => Schema m
schema = Schema query
query :: (Alternative m, Monad m) => ResolverM m
query fld =
withField "hero" hero fld
<|> withField "human" human fld
<|> withField "droid" droid fld
hero :: Alternative f => [Argument] -> ResolverO f
hero [] = characterFields artoo
hero args =
case withArgument "episode" args of
Just (ScalarInt n) -> characterFields $ getHero n
_ -> const empty
human :: (Alternative m, Monad m) => [Argument] -> ResolverO m
human args flds =
case withArgument "id" args of
Just (ScalarString i) -> flip characterFields flds =<< getHuman i
_ -> empty
droid :: (Alternative m, Monad m) => [Argument] -> ResolverO m
droid args flds =
case withArgument "id" args of
Just (ScalarString i) -> flip characterFields flds =<< getDroid i
_ -> empty
characterField :: Alternative f => Character -> ResolverM f
characterField char fld =
withFieldFinal "id" (OutputScalar . ScalarString . id_ $ char) fld
<|> withFieldFinal "name" (OutputScalar . ScalarString . name $ char) fld
<|> withField "friends" friends' fld
<|> withField "appearsIn" appears' fld
where
friends' [] flds = outputTraverse (`characterFields` flds) $ getFriends char
friends' _ _ = empty
appears' [] [] = outputTraverse (fmap OutputEnum . getEpisode) $ appearsIn char
appears' _ _ = empty
characterFields :: Alternative f => Character -> ResolverO f
characterFields = withFields . characterField