fix: willAddGraphQLTypeToSchema needs annotations from field (#1437)

Author: bherrmann2

generator/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/internal/extensions/annotationExtensions.kt

@@ -37,7 +37,7 @@ internal fun List<Annotation>.getUnionAnnotation(): GraphQLUnion? = this.filterI
 
 internal fun List<Annotation>.getCustomUnionClassWithMetaUnionAnnotation(): KClass<*>? = this.firstOrNull { it.getMetaUnionAnnotation() != null }?.annotationClass
 
-private fun Annotation.getMetaUnionAnnotation(): GraphQLUnion? = this.annotationClass.annotations.filterIsInstance(GraphQLUnion::class.java).firstOrNull()
+internal fun Annotation.getMetaUnionAnnotation(): GraphQLUnion? = this.annotationClass.annotations.filterIsInstance(GraphQLUnion::class.java).firstOrNull()
 
 internal fun List<Annotation>.getCustomTypeAnnotation(): GraphQLType? = this.filterIsInstance(GraphQLType::class.java).firstOrNull()
 

generator/graphql-kotlin-schema-generator/src/main/kotlin/com/expediagroup/graphql/generator/internal/types/generateGraphQLType.kt

@@ -21,6 +21,7 @@ import com.expediagroup.graphql.generator.extensions.unwrapType
 import com.expediagroup.graphql.generator.internal.extensions.getCustomTypeAnnotation
 import com.expediagroup.graphql.generator.internal.extensions.getCustomUnionClassWithMetaUnionAnnotation
 import com.expediagroup.graphql.generator.internal.extensions.getKClass
+import com.expediagroup.graphql.generator.internal.extensions.getMetaUnionAnnotation
 import com.expediagroup.graphql.generator.internal.extensions.getUnionAnnotation
 import com.expediagroup.graphql.generator.internal.extensions.isAnnotation
 import com.expediagroup.graphql.generator.internal.extensions.isEnum
@@ -32,6 +33,7 @@ import graphql.schema.GraphQLType
 import graphql.schema.GraphQLTypeReference
 import kotlin.reflect.KClass
 import kotlin.reflect.KType
+import kotlin.reflect.full.createType
 
 /**
  * Return a basic GraphQL type given all the information about the kotlin type.
@@ -63,7 +65,19 @@ private fun objectFromReflection(generator: SchemaGenerator, type: KType, typeIn
 
     return generator.cache.buildIfNotUnderConstruction(kClass, typeInfo) {
         val graphQLType = getGraphQLType(generator, kClass, type, typeInfo)
-        generator.config.hooks.willAddGraphQLTypeToSchema(type, graphQLType)
+
+        /*
+         * For a field using the meta union annotation, the `type` is `Any`, but we need to pass the annotation with the meta union annotation as the type
+         * since that is really the type generated from reflection and has any potential directives on it needed by the hook
+         */
+        val metaUnion = typeInfo.fieldAnnotations.firstOrNull { it.getMetaUnionAnnotation() != null }
+        val resolvedType = if (kClass.isInstance(Any::class) && metaUnion != null) {
+            metaUnion.annotationClass.createType()
+        } else {
+            type
+        }
+
+        generator.config.hooks.willAddGraphQLTypeToSchema(resolvedType, graphQLType)
     }
 }
 

generator/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/hooks/SchemaGeneratorHooksTest.kt

@@ -20,11 +20,13 @@ import com.expediagroup.graphql.generator.SchemaGenerator
 import com.expediagroup.graphql.generator.SchemaGeneratorConfig
 import com.expediagroup.graphql.generator.TopLevelObject
 import com.expediagroup.graphql.generator.annotations.GraphQLIgnore
+import com.expediagroup.graphql.generator.annotations.GraphQLUnion
 import com.expediagroup.graphql.generator.exceptions.EmptyInputObjectTypeException
 import com.expediagroup.graphql.generator.exceptions.EmptyInterfaceTypeException
 import com.expediagroup.graphql.generator.exceptions.EmptyObjectTypeException
 import com.expediagroup.graphql.generator.extensions.deepName
 import com.expediagroup.graphql.generator.getTestSchemaConfigWithHooks
+import com.expediagroup.graphql.generator.internal.extensions.getKClass
 import com.expediagroup.graphql.generator.internal.extensions.getSimpleName
 import com.expediagroup.graphql.generator.test.utils.graphqlUUIDType
 import com.expediagroup.graphql.generator.testSchemaConfig
@@ -36,6 +38,7 @@ import graphql.schema.GraphQLObjectType
 import graphql.schema.GraphQLScalarType
 import graphql.schema.GraphQLSchema
 import graphql.schema.GraphQLType
+import graphql.schema.GraphQLUnionType
 import graphql.schema.validation.InvalidSchemaException
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.reactive.asPublisher
@@ -221,19 +224,25 @@ class SchemaGeneratorHooksTest {
             override fun willAddGraphQLTypeToSchema(type: KType, generatedType: GraphQLType): GraphQLType {
                 hookCalled = true
                 return when {
-                    generatedType is GraphQLObjectType && generatedType.name == "SomeData" -> GraphQLObjectType.newObject(generatedType).description("My custom description").build()
-                    generatedType is GraphQLInterfaceType && generatedType.name == "RandomData" ->
+                    generatedType is GraphQLObjectType && generatedType.name == "SomeData" && type.getKClass() == SomeData::class ->
+                        GraphQLObjectType.newObject(generatedType).description("My custom description").build()
+                    generatedType is GraphQLInterfaceType && generatedType.name == "RandomData" && type.getKClass() == RandomData::class ->
                         GraphQLInterfaceType.newInterface(generatedType).description("My custom interface description").build()
+                    generatedType is GraphQLUnionType && generatedType.name == "MyMetaUnion" && type.getKClass() == MyMetaUnion::class ->
+                        GraphQLUnionType.newUnionType(generatedType).description("My meta union description").build()
+                    generatedType is GraphQLUnionType && generatedType.name == "MyAdditionalMetaUnion" && type.getKClass() == MyAdditionalMetaUnion::class ->
+                        GraphQLUnionType.newUnionType(generatedType).description("My additional meta union description").build()
                     else -> generatedType
                 }
             }
         }
 
         val hooks = MockSchemaGeneratorHooks()
-        val schema = toSchema(
-            queries = listOf(TopLevelObject(TestQuery())),
-            config = getTestSchemaConfigWithHooks(hooks)
-        )
+        val generator = SchemaGenerator(getTestSchemaConfigWithHooks(hooks))
+        val schema = generator.use {
+            it.generateSchema(queries = listOf(TopLevelObject(TestQuery())), additionalTypes = setOf(MyAdditionalMetaUnion::class.createType()))
+        }
+
         assertTrue(hooks.hookCalled)
 
         val type = schema.getObjectType("SomeData")
@@ -243,6 +252,14 @@ class SchemaGeneratorHooksTest {
         val interfaceType = schema.getType("RandomData") as? GraphQLInterfaceType
         assertNotNull(interfaceType)
         assertEquals(expected = "My custom interface description", actual = interfaceType.description)
+
+        val metaUnionType = schema.getType("MyMetaUnion") as? GraphQLUnionType
+        assertNotNull(metaUnionType)
+        assertEquals(expected = "My meta union description", actual = metaUnionType.description)
+
+        val additionalMetaUnionType = schema.getType("MyAdditionalMetaUnion") as? GraphQLUnionType
+        assertNotNull(additionalMetaUnionType)
+        assertEquals(expected = "My additional meta union description", actual = additionalMetaUnionType.description)
     }
 
     @Test
@@ -346,8 +363,16 @@ class SchemaGeneratorHooksTest {
 
     class TestQuery {
         fun query(): SomeData = SomeData("someData", 0)
+        @MyMetaUnion
+        fun unionQuery(): Any = SomeData("someData", 0)
     }
 
+    @GraphQLUnion(name = "MyMetaUnion", possibleTypes = [SomeData::class])
+    annotation class MyMetaUnion
+
+    @GraphQLUnion(name = "MyAdditionalMetaUnion", possibleTypes = [SomeData::class])
+    annotation class MyAdditionalMetaUnion
+
     class TestSubscription {
         fun subscription(): Publisher<SomeData> = flowOf(SomeData("someData", 0)).asPublisher()
     }

generator/graphql-kotlin-schema-generator/src/test/kotlin/com/expediagroup/graphql/generator/internal/extensions/AnnotationExtensionsTest.kt

@@ -110,6 +110,10 @@ class AnnotationExtensionsTest {
         assertNull(WithAnnotations::class.findMemberProperty("id")?.annotations?.getUnionAnnotation())
         @Suppress("DEPRECATION")
         assertNull(WithAnnotations::class.findMemberProperty("id")?.annotations?.getCustomUnionClassWithMetaUnionAnnotation())
+        @Suppress("DEPRECATION")
+        assertNotNull(WithAnnotations::class.findMemberProperty("metaUnion")?.annotations?.firstOrNull { it is MetaUnion }?.getMetaUnionAnnotation())
+        @Suppress("DEPRECATION")
+        assertNull(WithAnnotations::class.findMemberProperty("union")?.annotations?.firstOrNull { it is GraphQLUnion }?.getMetaUnionAnnotation())
     }
 
     private fun KClass<*>.findMemberProperty(name: String) = this.declaredMemberProperties.find { it.name == name }