server: remove built-in scalars from graphql schema printer

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6541
Co-authored-by: Auke Booij <164426+abooij@users.noreply.github.com>
GitOrigin-RevId: 5a2e35da2cf8718ee452429c56986066a3dc0c54

server/lib/graphql-parser-hs/src/Language/GraphQL/Draft/Printer.hs

@@ -124,6 +124,17 @@ instance Print Void where
 instance Print Name where
   printP = nameP
 
+-- Don't inline, to avoid the risk of unreasonably long code being generated
+{-# NOINLINE builtInScalars #-}
+builtInScalars :: [Name]
+builtInScalars =
+  [ Name.Name "Boolean",
+    Name.Name "Float",
+    Name.Name "ID",
+    Name.Name "Int",
+    Name.Name "String"
+  ]
+
 renderExecutableDoc :: ExecutableDocument Name -> Text
 renderExecutableDoc = Text.run . executableDocument
 
@@ -353,7 +364,17 @@ typeSystemDefinition (TypeSystemDefinitionType typeDefn) = typeDefinitionP typeD
 
 schemaDocument :: Printer a => SchemaDocument -> a
 schemaDocument (SchemaDocument typeDefns) =
-  mconcat $ intersperse (textP "\n\n") $ map typeSystemDefinition $ sort typeDefns
+  mconcat $ intersperse (textP "\n\n") $ map typeSystemDefinition $ sort $ filter isNotBuiltInScalar typeDefns
+  where
+    -- According to https://spec.graphql.org/June2018/#sec-Scalars:
+    --   > When representing a GraphQL schema using the type system definition language, the built‐in scalar types should
+    --   > be omitted for brevity.
+    isNotBuiltInScalar :: TypeSystemDefinition -> Bool
+    isNotBuiltInScalar
+      ( TypeSystemDefinitionType
+          (TypeDefinitionScalar (ScalarTypeDefinition _ name _))
+        ) = name `notElem` builtInScalars
+    isNotBuiltInScalar _ = True
 
 typeDefinitionP :: Printer a => TypeDefinition () InputValueDefinition -> a
 typeDefinitionP (TypeDefinitionScalar scalarDefn) = scalarTypeDefinition scalarDefn

server/src-lib/Hasura/GraphQL/ApolloFederation.hs

@@ -14,6 +14,7 @@ import Data.Aeson qualified as J
 import Data.Aeson.Key qualified as K
 import Data.Aeson.KeyMap qualified as KMap
 import Data.Aeson.Ordered qualified as JO
+import Data.Bifunctor (Bifunctor (bimap))
 import Data.HashMap.Strict qualified as Map
 import Data.HashMap.Strict.InsOrd qualified as OMap
 import Data.HashSet qualified as Set
@@ -194,7 +195,7 @@ generateSDL (G.SchemaIntrospection sIntro) = sdl
 
     -- first we filter out the type definitions which are not relevent such as
     -- schema fields and types (starts with `__`)
-    typeDefns = mapMaybe filterAndWrapTypeSystemDefinition (Map.elems sIntro)
+    typeDefns = map (G.TypeSystemDefinitionType . filterTypeDefinition . bimap (const ()) id) (Map.elems sIntro)
 
     -- next we get the root operation type definitions
     rootOpTypeDefns =
@@ -214,22 +215,16 @@ generateSDL (G.SchemaIntrospection sIntro) = sdl
     getSchemaDocument :: G.SchemaDocument
     getSchemaDocument =
       G.SchemaDocument $
-        G.TypeSystemDefinitionSchema (G.SchemaDefinition Nothing (rootOpTypeDefns)) : typeDefns
+        G.TypeSystemDefinitionSchema (G.SchemaDefinition Nothing rootOpTypeDefns) : typeDefns
 
--- | Filter out schema components from sdl which are not required by apollo federation and
--- wraps it in `TypeSystemDefinition`
-filterAndWrapTypeSystemDefinition :: G.TypeDefinition [G.Name] G.InputValueDefinition -> Maybe G.TypeSystemDefinition
-filterAndWrapTypeSystemDefinition = \case
-  G.TypeDefinitionScalar (G.ScalarTypeDefinition {}) -> Nothing
-  G.TypeDefinitionInterface (G.InterfaceTypeDefinition a b c d _) ->
-    Just $ G.TypeSystemDefinitionType (G.TypeDefinitionInterface (G.InterfaceTypeDefinition a b c d ()))
+-- | Filter out schema components from sdl which are not required by apollo federation
+filterTypeDefinition :: G.TypeDefinition possibleTypes G.InputValueDefinition -> G.TypeDefinition possibleTypes G.InputValueDefinition
+filterTypeDefinition = \case
   G.TypeDefinitionObject (G.ObjectTypeDefinition a b c d e) ->
     -- We are skipping the schema types here
-    Just . G.TypeSystemDefinitionType . G.TypeDefinitionObject $
+    G.TypeDefinitionObject $
       G.ObjectTypeDefinition a b c d (filter (not . T.isPrefixOf "__" . G.unName . G._fldName) e)
-  G.TypeDefinitionUnion defn -> Just $ G.TypeSystemDefinitionType (G.TypeDefinitionUnion defn)
-  G.TypeDefinitionEnum defn -> Just $ G.TypeSystemDefinitionType (G.TypeDefinitionEnum defn)
-  G.TypeDefinitionInputObject defn -> Just $ G.TypeSystemDefinitionType (G.TypeDefinitionInputObject defn)
+  typeDef -> typeDef
 
 -------------------------------------------------------------------------------
 -- Related to @_entities@ field