Access to configure possibleTypes via TypeDSL for sealed union types

Author: jeggy

gradle.properties

@@ -1,5 +1,5 @@
 # KGraphQL version
-version=0.17.12
+version=0.17.13
 
 # Dependencies
 coroutine_version=1.5.0

kgraphql/src/main/kotlin/com/apurebase/kgraphql/schema/dsl/SchemaBuilder.kt

@@ -195,8 +195,11 @@ class SchemaBuilder internal constructor() {
         if (!T::class.isSealed) throw SchemaException("Can't generate a union type out of a non sealed class. '${T::class.simpleName}'")
 
         return unionType(T::class.simpleName!!) {
-            T::class.sealedSubclasses.forEach { type(it) }
             block()
+            T::class.sealedSubclasses.forEach {
+                type(it, subTypeBlock) // <-- Adds to schema definition
+                type(it) // <-- Adds to possible union type
+            }
         }
     }
 

kgraphql/src/main/kotlin/com/apurebase/kgraphql/schema/dsl/types/UnionTypeDSL.kt

@@ -8,11 +8,13 @@ class UnionTypeDSL() : ItemDSL() {
 
     internal val possibleTypes = mutableSetOf<KClass<*>>()
 
+    var subTypeBlock: TypeDSL<*>.() -> Unit = {}
+
     fun <T : Any>type(kClass : KClass<T>){
         possibleTypes.add(kClass)
     }
 
     inline fun <reified T : Any>type(){
         type(T::class)
     }
-}
+}

kgraphql/src/main/kotlin/com/apurebase/kgraphql/schema/model/MutableSchemaDefinition.kt

@@ -61,7 +61,7 @@ data class MutableSchemaDefinition (
 
         unions.forEach { union ->
             if(union.members.isEmpty()){
-                throw SchemaException("A Union type must define one or more unique member types")
+                throw SchemaException("The union type '${union.name}' has no possible types defined, requires at least one. Please refer to https://kgraphql.io/Reference/Type%20System/unions/")
             }
             union.members.forEach { member ->
                 validateUnionMember(union, member, compiledObjects)

kgraphql/src/test/kotlin/com/apurebase/kgraphql/specification/typesystem/UnionsSpecificationTest.kt

@@ -6,7 +6,6 @@ import com.apurebase.kgraphql.schema.SchemaException
 import com.apurebase.kgraphql.GraphQLError
 import com.apurebase.kgraphql.helpers.getFields
 import com.apurebase.kgraphql.schema.execution.Execution
-import kotlinx.coroutines.test.runBlockingTest
 import org.amshove.kluent.*
 import org.hamcrest.CoreMatchers
 import org.hamcrest.MatcherAssert
@@ -136,7 +135,7 @@ class UnionsSpecificationTest : BaseSchemaTest() {
 
     @Test
     fun `A Union type must define one or more unique member types`(){
-        expect<SchemaException>("A Union type must define one or more unique member types"){
+        expect<SchemaException>("The union type 'invalid' has no possible types defined, requires at least one. Please refer to https://kgraphql.io/Reference/Type%20System/unions/") {
             KGraphQL.schema {
                 unionType("invalid") {}
             }
@@ -241,4 +240,33 @@ class UnionsSpecificationTest : BaseSchemaTest() {
             extract<List<String>>("data/returnUnion/fields") shouldBeEqualTo listOf("i", "fields", "s")
         }
     }
+
+    @Test
+    fun `union types with custom name def resolver`() {
+        defaultSchema {
+            unionType<WithFields> {
+                subTypeBlock = {
+                    name = "Prefix$name"
+                }
+            }
+
+            query("returnUnion") {
+                resolver { node: Execution.Node ->
+                    listOf(
+                        WithFields.Value1(1, node.getFields()),
+                        WithFields.Value2("key", node.getFields()),
+                    )
+                }
+            }
+        }.executeBlocking("""
+            {
+                returnUnion {
+                    __typename
+                }
+            }
+        """.trimIndent()).also(::println).deserialize().run {
+            extract<String>("data/returnUnion[0]/__typename") shouldBeEqualTo "PrefixValue1"
+            extract<String>("data/returnUnion[1]/__typename") shouldBeEqualTo "PrefixValue2"
+        }
+    }
 }