graphql/tests/Test/StarWars/Schema.hs
Eugen Wissner e24386402b Respect subscriptions in the executor
After the last commit there were a few places needed to be adjusted to
support subscriptions. This is done and a test case is added.

It is important to implement subscriptions now, because they require
changes to the library API, and they are a big missing part to finish
the executor. When the executor is finished, we can start to provide
more stable API without breaking everything every release. Validation
and introspection shouldn't require much changes to the API; AST would
require some changes to report good errors after the validation - this
is one thing I can think of.

Fixes #5.
2020-07-15 19:15:31 +02:00

157 lines
5.1 KiB
Haskell

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE ScopedTypeVariables #-}
module Test.StarWars.Schema
( schema
) where
import Control.Monad.Trans.Reader (asks)
import Control.Monad.Trans.Except (throwE)
import Control.Monad.Trans.Class (lift)
import Data.Functor.Identity (Identity)
import qualified Data.HashMap.Strict as HashMap
import Data.Maybe (catMaybes)
import Data.Text (Text)
import Language.GraphQL.Type
import qualified Language.GraphQL.Type.In as In
import qualified Language.GraphQL.Type.Out as Out
import Test.StarWars.Data
import Prelude hiding (id)
-- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsSchema.js
schema :: Schema Identity
schema = Schema
{ query = queryType
, mutation = Nothing
, subscription = Nothing
}
where
queryType = Out.ObjectType "Query" Nothing [] $ HashMap.fromList
[ ("hero", heroFieldResolver)
, ("human", humanFieldResolver)
, ("droid", droidFieldResolver)
]
heroField = Out.Field Nothing (Out.NamedObjectType heroObject)
$ HashMap.singleton "episode"
$ In.Argument Nothing (In.NamedEnumType episodeEnum) Nothing
heroFieldResolver = ValueResolver heroField hero
humanField = Out.Field Nothing (Out.NamedObjectType heroObject)
$ HashMap.singleton "id"
$ In.Argument Nothing (In.NonNullScalarType string) Nothing
humanFieldResolver = ValueResolver humanField human
droidField = Out.Field Nothing (Out.NamedObjectType droidObject) mempty
droidFieldResolver = ValueResolver droidField droid
heroObject :: Out.ObjectType Identity
heroObject = Out.ObjectType "Human" Nothing [] $ HashMap.fromList
[ ("id", idFieldType)
, ("name", nameFieldType)
, ("friends", friendsFieldType)
, ("appearsIn", appearsInField)
, ("homePlanet", homePlanetFieldType)
, ("secretBackstory", secretBackstoryFieldType)
, ("__typename", typenameFieldType)
]
where
homePlanetFieldType
= ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
$ idField "homePlanet"
droidObject :: Out.ObjectType Identity
droidObject = Out.ObjectType "Droid" Nothing [] $ HashMap.fromList
[ ("id", idFieldType)
, ("name", nameFieldType)
, ("friends", friendsFieldType)
, ("appearsIn", appearsInField)
, ("primaryFunction", primaryFunctionFieldType)
, ("secretBackstory", secretBackstoryFieldType)
, ("__typename", typenameFieldType)
]
where
primaryFunctionFieldType
= ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
$ idField "primaryFunction"
typenameFieldType :: Resolver Identity
typenameFieldType
= ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
$ idField "__typename"
idFieldType :: Resolver Identity
idFieldType
= ValueResolver (Out.Field Nothing (Out.NamedScalarType id) mempty)
$ idField "id"
nameFieldType :: Resolver Identity
nameFieldType
= ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
$ idField "name"
friendsFieldType :: Resolver Identity
friendsFieldType
= ValueResolver (Out.Field Nothing fieldType mempty)
$ idField "friends"
where
fieldType = Out.ListType $ Out.NamedObjectType droidObject
appearsInField :: Resolver Identity
appearsInField
= ValueResolver (Out.Field (Just description) fieldType mempty)
$ idField "appearsIn"
where
fieldType = Out.ListType $ Out.NamedEnumType episodeEnum
description = "Which movies they appear in."
secretBackstoryFieldType :: Resolver Identity
secretBackstoryFieldType = ValueResolver field secretBackstory
where
field = Out.Field Nothing (Out.NamedScalarType string) mempty
idField :: Text -> Resolve Identity
idField f = do
v <- lift $ asks values
let (Object v') = v
pure $ v' HashMap.! f
episodeEnum :: EnumType
episodeEnum = EnumType "Episode" (Just description)
$ HashMap.fromList [newHope, empire, jedi]
where
description = "One of the films in the Star Wars Trilogy"
newHope = ("NEW_HOPE", EnumValue $ Just "Released in 1977.")
empire = ("EMPIRE", EnumValue $ Just "Released in 1980.")
jedi = ("JEDI", EnumValue $ Just "Released in 1983.")
hero :: Resolve Identity
hero = do
episode <- argument "episode"
pure $ character $ case episode of
Enum "NEW_HOPE" -> getHero 4
Enum "EMPIRE" -> getHero 5
Enum "JEDI" -> getHero 6
_ -> artoo
human :: Resolve Identity
human = do
id' <- argument "id"
case id' of
String i -> pure $ maybe Null character $ getHuman i >>= Just
_ -> throwE "Invalid arguments."
droid :: Resolve Identity
droid = do
id' <- argument "id"
case id' of
String i -> pure $ maybe Null character $ getDroid i >>= Just
_ -> throwE "Invalid arguments."
character :: Character -> Value
character char = Object $ HashMap.fromList
[ ("id", String $ id_ char)
, ("name", String $ name_ char)
, ("friends", List $ character <$> getFriends char)
, ("appearsIn", List $ Enum <$> catMaybes (getEpisode <$> appearsIn char))
, ("homePlanet", String $ either mempty homePlanet char)
, ("__typename", String $ typeName char)
]