feat: allow to use alias directives for import in federation 2

Author: greguintow

packages/graphql/lib/federation/graphql-federation.factory.ts

@@ -28,7 +28,7 @@ import { GraphQLSchemaBuilder } from '../graphql-schema.builder';
 import { GraphQLSchemaHost } from '../graphql-schema.host';
 import { GqlModuleOptions, BuildFederatedSchemaOptions } from '../interfaces';
 import { ResolversExplorerService, ScalarsExplorerService } from '../services';
-import { extend } from '../utils';
+import { extend, stringifyWithoutQuotes } from '../utils';
 import { transformSchema } from '../utils/transform-schema.util';
 
 @Injectable()
@@ -122,10 +122,13 @@ export class GraphQLFederationFactory {
           '@override',
           '@requires',
         ],
-        url = 'https://specs.apollo.dev/federation/v2.0',
+        importUrl = 'https://specs.apollo.dev/federation/v2.0',
       } = typeof options.useFed2 === 'boolean' ? {} : options.useFed2;
       const mappedDirectives = directives
         .map((directive) => {
+          if (!isString(directive)) {
+            return stringifyWithoutQuotes(directive);
+          }
           let finalDirective = directive;
           if (!directive.startsWith('@')) {
             finalDirective = `@${directive}`;
@@ -135,7 +138,7 @@ export class GraphQLFederationFactory {
         .join(', ');
 
       typeDefs = `
-        extend schema @link(url: "${url}", import: [${mappedDirectives}])
+        extend schema @link(url: "${importUrl}", import: [${mappedDirectives}])
         ${typeDefs}
       `;
     } else if (options.useFed2 && !isApolloSubgraph2) {

packages/graphql/lib/interfaces/gql-module-options.interface.ts

@@ -8,17 +8,22 @@ import { BuildSchemaOptions } from './build-schema-options.interface';
 
 export type Enhancer = 'guards' | 'interceptors' | 'filters';
 
+export interface AliasDirectiveImport {
+  name: string;
+  as: string;
+}
+
 export interface Federation2Config {
   /**
    * The imported directives
    * @default ['@key', '@shareable', '@external', '@override', '@requires']
    */
-  directives?: string[];
+  directives?: (string | AliasDirectiveImport)[];
   /**
    * The import link
    * @default 'https://specs.apollo.dev/federation/v2.0'
    */
-  url?: string;
+  importUrl?: string;
 }
 
 /**
@@ -51,7 +56,9 @@ export interface GqlModuleOptions<TDriver extends GraphQLDriver = any> {
   include?: Function[];
 
   /**
-   * Defines if wants to federation 2
+   * If enabled, it will use federation 2 schema
+   * 
+   * **Note:** You need to have installed @apollo/subgraph@^2.0.0 and enable `autoSchemaFile`
    * 
    * This will add to your schema:
    * ```graphql