graphql/tests/Test/StarWars/Data.hs
Eugen Wissner 91679650b5 Introduce monad transformer for resolvers
Now the errors in the resolvers can be handled and 3 tests throwing
errors pass now. Another test fail but it requires distinguisching
nullable and non-nullable values.
2019-07-02 20:07:26 +02:00

180 lines
4.0 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
module Test.StarWars.Data where
import Data.Monoid (mempty)
import Control.Applicative (liftA2)
import Control.Monad (MonadPlus(..))
import Control.Monad.Trans.Except (throwE)
import Data.Maybe (catMaybes)
import Data.Text (Text)
import Language.GraphQL.Trans
-- * Data
-- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsData.js
-- ** Characters
type ID = Text
data CharCommon = CharCommon
{ _id_ :: ID
, _name :: Text
, _friends :: [ID]
, _appearsIn :: [Int]
} deriving (Show)
data Human = Human
{ _humanChar :: CharCommon
, homePlanet :: Text
}
data Droid = Droid
{ _droidChar :: CharCommon
, primaryFunction :: Text
}
type Character = Either Droid Human
id_ :: Character -> ID
id_ (Left x) = _id_ . _droidChar $ x
id_ (Right x) = _id_ . _humanChar $ x
name :: Character -> Text
name (Left x) = _name . _droidChar $ x
name (Right x) = _name . _humanChar $ x
friends :: Character -> [ID]
friends (Left x) = _friends . _droidChar $ x
friends (Right x) = _friends . _humanChar $ x
appearsIn :: Character -> [Int]
appearsIn (Left x) = _appearsIn . _droidChar $ x
appearsIn (Right x) = _appearsIn . _humanChar $ x
secretBackstory :: MonadPlus m => Character -> ActionT m Text
secretBackstory = const $ ActionT $ throwE "secretBackstory is secret."
typeName :: Character -> Text
typeName = either (const "Droid") (const "Human")
luke :: Character
luke = Right luke'
luke' :: Human
luke' = Human
{ _humanChar = CharCommon
{ _id_ = "1000"
, _name = "Luke Skywalker"
, _friends = ["1002","1003","2000","2001"]
, _appearsIn = [4,5,6]
}
, homePlanet = "Tatooine"
}
vader :: Human
vader = Human
{ _humanChar = CharCommon
{ _id_ = "1001"
, _name = "Darth Vader"
, _friends = ["1004"]
, _appearsIn = [4,5,6]
}
, homePlanet = "Tatooine"
}
han :: Human
han = Human
{ _humanChar = CharCommon
{ _id_ = "1002"
, _name = "Han Solo"
, _friends = ["1000","1003","2001" ]
, _appearsIn = [4,5,6]
}
, homePlanet = mempty
}
leia :: Human
leia = Human
{ _humanChar = CharCommon
{ _id_ = "1003"
, _name = "Leia Organa"
, _friends = ["1000","1002","2000","2001"]
, _appearsIn = [4,5,6]
}
, homePlanet = "Alderaan"
}
tarkin :: Human
tarkin = Human
{ _humanChar = CharCommon
{ _id_ = "1004"
, _name = "Wilhuff Tarkin"
, _friends = ["1001"]
, _appearsIn = [4]
}
, homePlanet = mempty
}
threepio :: Droid
threepio = Droid
{ _droidChar = CharCommon
{ _id_ = "2000"
, _name = "C-3PO"
, _friends = ["1000","1002","1003","2001" ]
, _appearsIn = [ 4, 5, 6 ]
}
, primaryFunction = "Protocol"
}
artoo :: Character
artoo = Left artoo'
artoo' :: Droid
artoo' = Droid
{ _droidChar = CharCommon
{ _id_ = "2001"
, _name = "R2-D2"
, _friends = ["1000","1002","1003"]
, _appearsIn = [4,5,6]
}
, primaryFunction = "Astrometch"
}
-- ** Helper functions
getHero :: Int -> Character
getHero 5 = luke
getHero _ = artoo
getHeroIO :: Int -> IO Character
getHeroIO = pure . getHero
getHuman :: MonadPlus m => ID -> m Character
getHuman = fmap Right . getHuman'
getHuman' :: MonadPlus m => ID -> m Human
getHuman' "1000" = pure luke'
getHuman' "1001" = pure vader
getHuman' "1002" = pure han
getHuman' "1003" = pure leia
getHuman' "1004" = pure tarkin
getHuman' _ = mzero
getDroid :: MonadPlus m => ID -> m Character
getDroid = fmap Left . getDroid'
getDroid' :: MonadPlus m => ID -> m Droid
getDroid' "2000" = pure threepio
getDroid' "2001" = pure artoo'
getDroid' _ = mzero
getFriends :: Character -> [Character]
getFriends char = catMaybes $ liftA2 mplus getDroid getHuman <$> friends char
getEpisode :: MonadPlus m => Int -> m Text
getEpisode 4 = pure "NEWHOPE"
getEpisode 5 = pure "EMPIRE"
getEpisode 6 = pure "JEDI"
getEpisode _ = mzero