feat: implement @defer directive

composition-go/composition_test.go

@@ -70,6 +70,8 @@ func TestFederateSubgraphs(t *testing.T) {
 		expectedSDL = `
 			directive @authenticated on ENUM | FIELD_DEFINITION | INTERFACE | OBJECT | SCALAR
 
+			directive @defer(if: Boolean! = true, label: String) on FRAGMENT_SPREAD | INLINE_FRAGMENT
+
 			directive @deprecated(reason: String = "No longer supported") on ARGUMENT_DEFINITION | ENUM_VALUE | FIELD_DEFINITION | INPUT_FIELD_DEFINITION
 
 			directive @inaccessible on ARGUMENT_DEFINITION | ENUM | ENUM_VALUE | FIELD_DEFINITION | INPUT_FIELD_DEFINITION | INPUT_OBJECT | INTERFACE | OBJECT | SCALAR | UNION

composition/src/federation/federation-factory.ts

@@ -130,6 +130,7 @@ import {
 import {
   AUTHENTICATED_DEFINITION,
   BASE_SCALARS,
+  DEFER_DEFINITION,
   DEPRECATED_DEFINITION,
   INACCESSIBLE_DEFINITION,
   REQUIRES_SCOPES_DEFINITION,
@@ -193,7 +194,7 @@ import { Warning } from '../warnings/warnings';
 export class FederationFactory {
   authorizationDataByParentTypeName: Map<string, AuthorizationData>;
   concreteTypeNamesByAbstractTypeName: Map<string, Set<string>>;
-  clientDefinitions: MutableTypeDefinitionNode[] = [DEPRECATED_DEFINITION];
+  clientDefinitions: MutableTypeDefinitionNode[] = [DEFER_DEFINITION, DEPRECATED_DEFINITION];
   currentSubgraphName = '';
   entityDataByTypeName: Map<string, EntityData>;
   entityInterfaceFederationDataByTypeName: Map<string, EntityInterfaceFederationData>;
@@ -220,7 +221,7 @@ export class FederationFactory {
   ]);
   persistedDirectiveDefinitions = new Set<string>([AUTHENTICATED, DEPRECATED, INACCESSIBLE, TAG, REQUIRES_SCOPES]);
   potentialPersistedDirectiveDefinitionDataByDirectiveName = new Map<string, PersistedDirectiveDefinitionData>();
-  routerDefinitions: MutableTypeDefinitionNode[] = [DEPRECATED_DEFINITION, TAG_DEFINITION];
+  routerDefinitions: MutableTypeDefinitionNode[] = [DEFER_DEFINITION, DEPRECATED_DEFINITION, TAG_DEFINITION];
   shareableErrorTypeNames = new Map<string, Set<string>>();
   subscriptionFilterDataByFieldPath = new Map<string, SubscriptionFilterData>();
   isMaxDepth = false;
@@ -1546,6 +1547,7 @@ export class FederationFactory {
     }
     this.routerDefinitions = [
       AUTHENTICATED_DEFINITION,
+      DEFER_DEFINITION,
       DEPRECATED_DEFINITION,
       INACCESSIBLE_DEFINITION,
       REQUIRES_SCOPES_DEFINITION,
@@ -1554,6 +1556,7 @@ export class FederationFactory {
     ];
     this.clientDefinitions = [
       AUTHENTICATED_DEFINITION,
+      DEFER_DEFINITION,
       DEPRECATED_DEFINITION,
       REQUIRES_SCOPES_DEFINITION,
       SCOPE_SCALAR_DEFINITION,

composition/src/utils/constants.ts

@@ -15,6 +15,7 @@ import {
   CONDITION,
   CONSUMER_NAME,
   DEFAULT_EDFS_PROVIDER_ID,
+  DEFER,
   DEPRECATED,
   EDFS_KAFKA_PUBLISH,
   EDFS_KAFKA_SUBSCRIBE,
@@ -30,14 +31,18 @@ import {
   FIELD_PATH,
   FIELD_SET_SCALAR,
   FIELDS,
+  FRAGMENT_SPREAD_UPPER,
   FROM,
+  IF,
   IN_UPPER,
   INACCESSIBLE,
+  INLINE_FRAGMENT_UPPER,
   INPUT_FIELD_DEFINITION_UPPER,
   INPUT_OBJECT_UPPER,
   INTERFACE_OBJECT,
   INTERFACE_UPPER,
   KEY,
+  LABEL,
   LINK,
   NAME,
   NOT_UPPER,
@@ -769,6 +774,34 @@ export const EDFS_NATS_STREAM_CONFIGURATION_DEFINITION: MutableInputObjectNode =
   ],
 };
 
+export const DEFER_DEFINITION: MutableDirectiveDefinitionNode = {
+  arguments: [
+    {
+      directives: [],
+      kind: Kind.INPUT_VALUE_DEFINITION,
+      name: stringToNameNode(IF),
+      type: {
+        kind: Kind.NON_NULL_TYPE,
+        type: stringToNamedTypeNode(BOOLEAN_SCALAR),
+      },
+      defaultValue: {
+        kind: Kind.BOOLEAN,
+        value: true,
+      },
+    },
+    {
+      directives: [],
+      kind: Kind.INPUT_VALUE_DEFINITION,
+      name: stringToNameNode(LABEL),
+      type: stringToNamedTypeNode(STRING_SCALAR),
+    },
+  ],
+  kind: Kind.DIRECTIVE_DEFINITION,
+  locations: stringArrayToNameNodeArray([FRAGMENT_SPREAD_UPPER, INLINE_FRAGMENT_UPPER]),
+  name: stringToNameNode(DEFER),
+  repeatable: false,
+};
+
 export const INHERITABLE_DIRECTIVE_NAMES = [EXTERNAL, SHAREABLE];
 
 export const baseDirectives = `

composition/src/utils/string-constants.ts

@@ -13,6 +13,7 @@ export const DEFAULT_EDFS_PROVIDER_ID = 'default';
 export const DEFAULT_MUTATION = 'Mutation';
 export const DEFAULT_QUERY = 'Query';
 export const DEFAULT_SUBSCRIPTION = 'Subscription';
+export const DEFER = 'defer';
 export const DEPRECATED = 'deprecated';
 export const DEPRECATED_DEFAULT_ARGUMENT_VALUE = 'No longer supported';
 export const DIRECTIVE_DEFINITION = 'directive definition';
@@ -43,6 +44,7 @@ export const FLOAT_SCALAR = 'Float';
 export const FRAGMENT_DEFINITION_UPPER = 'FRAGMENT_DEFINITION';
 export const FRAGMENT_SPREAD_UPPER = 'FRAGMENT_SPREAD';
 export const FROM = 'from';
+export const IF = 'if';
 export const IN_UPPER = 'IN';
 export const INACCESSIBLE = 'inaccessible';
 export const INLINE_FRAGMENT = 'inlineFragment';
@@ -57,6 +59,7 @@ export const INTERFACE = `Interface`;
 export const INTERFACE_UPPER = 'INTERFACE';
 export const INTERFACE_OBJECT = 'interfaceObject';
 export const KEY = 'key';
+export const LABEL = 'label';
 export const LINK = 'link';
 export const LIST = 'list';
 export const LITERAL_SPACE = ' ';