chore(): resolve merge conflicts

lib/federation/graphql-federation.module.ts

@@ -2,6 +2,7 @@ import {
   DynamicModule,
   Inject,
   Module,
+  OnModuleDestroy,
   OnModuleInit,
   Optional,
   Provider,
@@ -54,8 +55,12 @@ import { GraphQLFederationFactory } from './graphql-federation.factory';
   ],
   exports: [GraphQLSchemaHost, GraphQLTypesLoader, GraphQLAstExplorer],
 })
-export class GraphQLFederationModule implements OnModuleInit {
-  private apolloServer: ApolloServerBase;
+export class GraphQLFederationModule implements OnModuleInit, OnModuleDestroy {
+  private _apolloServer: ApolloServerBase;
+
+  get apolloServer(): ApolloServerBase {
+    return this._apolloServer;
+  }
 
   constructor(
     @Optional()
@@ -173,6 +178,10 @@ export class GraphQLFederationModule implements OnModuleInit {
     }
   }
 
+  async onModuleDestroy() {
+    await this._apolloServer?.stop();
+  }
+
   private registerGqlServer(apolloOptions: GqlModuleOptions) {
     const httpAdapter = this.httpAdapterHost.httpAdapter;
     const platformName = httpAdapter.getType();
@@ -220,7 +229,7 @@ export class GraphQLFederationModule implements OnModuleInit {
       cors,
       bodyParserConfig,
     });
-    this.apolloServer = apolloServer;
+    this._apolloServer = apolloServer;
   }
 
   private registerFastify(apolloOptions: GqlModuleOptions) {
@@ -261,7 +270,7 @@ export class GraphQLFederationModule implements OnModuleInit {
       }),
     );
 
-    this.apolloServer = apolloServer;
+    this._apolloServer = apolloServer;
   }
 
   private getNormalizedPath(apolloOptions: GqlModuleOptions): string {

lib/graphql.module.ts

@@ -1,8 +1,8 @@
 import { Inject, Module } from '@nestjs/common';
 import {
   DynamicModule,
-  OnModuleInit,
   OnModuleDestroy,
+  OnModuleInit,
   Provider,
 } from '@nestjs/common/interfaces';
 import { loadPackage } from '@nestjs/common/utils/load-package.util';
@@ -50,7 +50,12 @@ import {
   exports: [GraphQLTypesLoader, GraphQLAstExplorer, GraphQLSchemaHost],
 })
 export class GraphQLModule implements OnModuleInit, OnModuleDestroy {
-  protected apolloServer: ApolloServerBase;
+  private _apolloServer: ApolloServerBase;
+
+  get apolloServer(): ApolloServerBase {
+    return this._apolloServer;
+  }
+
   constructor(
     private readonly httpAdapterHost: HttpAdapterHost,
     @Inject(GRAPHQL_MODULE_OPTIONS) private readonly options: GqlModuleOptions,
@@ -149,14 +154,14 @@ export class GraphQLModule implements OnModuleInit, OnModuleDestroy {
 
     this.registerGqlServer(apolloOptions);
     if (this.options.installSubscriptionHandlers) {
-      this.apolloServer.installSubscriptionHandlers(
+      this._apolloServer.installSubscriptionHandlers(
         httpAdapter.getHttpServer(),
       );
     }
   }
 
   async onModuleDestroy() {
-    await this.apolloServer?.stop();
+    await this._apolloServer?.stop();
   }
 
   private registerGqlServer(apolloOptions: GqlModuleOptions) {
@@ -199,7 +204,7 @@ export class GraphQLModule implements OnModuleInit, OnModuleDestroy {
       bodyParserConfig,
     });
 
-    this.apolloServer = apolloServer;
+    this._apolloServer = apolloServer;
   }
 
   private registerFastify(apolloOptions: GqlModuleOptions) {
@@ -230,7 +235,7 @@ export class GraphQLModule implements OnModuleInit, OnModuleDestroy {
       }),
     );
 
-    this.apolloServer = apolloServer;
+    this._apolloServer = apolloServer;
   }
 
   private getNormalizedPath(apolloOptions: GqlModuleOptions): string {

lib/index.ts

@@ -14,3 +14,4 @@ export * from './services/gql-execution-context';
 export * from './tokens';
 export * from './type-factories';
 export * from './type-helpers';
+export { getApolloServer } from './utils';

lib/utils/get-apollo-server.ts

@@ -0,0 +1,25 @@
+import { INestApplicationContext } from '@nestjs/common';
+import { ApolloServerBase } from 'apollo-server-core';
+import { GraphQLFederationModule, GraphQLModule } from '..';
+
+/**
+ * Returns the underlying ApolloServer instance for a given application.
+ * Supports both Apollo federation and regular GraphQL applications.
+ * @param app Nest application reference
+ * @returns Apollo Server instance used by the host application
+ */
+export function getApolloServer(
+  app: INestApplicationContext,
+): ApolloServerBase {
+  try {
+    const graphqlFederationModule = app.get(GraphQLFederationModule);
+    return graphqlFederationModule.apolloServer;
+  } catch (error) {}
+  try {
+    const graphqlModule = app.get(GraphQLModule);
+    return graphqlModule.apolloServer;
+  } catch (error) {}
+  throw new Error(
+    'Nest could not find either the GraphQLFederationModule or GraphQLModule. Neither module is registered in the given application.',
+  );
+}

lib/utils/index.ts

@@ -5,3 +5,4 @@ export * from './generate-token.util';
 export * from './merge-defaults.util';
 export * from './normalize-route-path.util';
 export * from './remove-temp.util';
+export * from './get-apollo-server';

package.json

@@ -37,6 +37,7 @@
     "@typescript-eslint/parser": "4.6.1",
     "apollo-server-express": "2.16.1",
     "apollo-server-fastify": "2.16.1",
+    "apollo-server-testing": "2.16.1",
     "class-transformer": "0.3.1",
     "class-validator": "0.12.2",
     "eslint": "7.13.0",

tests/e2e/code-first-federation.spec.ts

@@ -1,10 +1,13 @@
 import { INestApplication } from '@nestjs/common';
 import { Test } from '@nestjs/testing';
-import * as request from 'supertest';
+import { gql } from 'apollo-server-express';
+import { ApolloServerTestClient } from 'apollo-server-testing';
 import { ApplicationModule } from '../code-first-federation/app.module';
+import { createTestClient } from '../utils/create-test-client';
 
 describe('Code-first - Federation', () => {
   let app: INestApplication;
+  let apolloClient: ApolloServerTestClient;
 
   beforeEach(async () => {
     const module = await Test.createTestingModule({
@@ -13,36 +16,30 @@ describe('Code-first - Federation', () => {
 
     app = module.createNestApplication();
     await app.init();
+    apolloClient = createTestClient(module);
   });
 
-  it(`should return query result`, () => {
-    return request(app.getHttpServer())
-      .post('/graphql')
-      .send({
-        operationName: null,
-        variables: {},
-        query: `
+  it(`should return query result`, async () => {
+    const response = await apolloClient.query({
+      query: gql`
         {
-          _service { sdl }
-        }`,
-      })
-      .expect(200, {
-        data: {
-          _service: {
-            sdl:
-              '"Search result description"\nunion FederationSearchResultUnion = Post | User\n\ntype Post @key(fields: "id") {\n  id: ID!\n  title: String!\n  authorId: Int!\n}\n\ntype Query {\n  findPost(id: Float!): Post!\n  getPosts: [Post!]!\n  search: [FederationSearchResultUnion!]! @deprecated(reason: "test")\n}\n\ntype User @extends @key(fields: "id") {\n  id: ID! @external\n  posts: [Post!]!\n}\n',
-          },
-        },
-      });
+          _service {
+            sdl
+          }
+        }
+      `,
+    });
+    expect(response.data).toEqual({
+      _service: {
+        sdl:
+          '"Search result description"\nunion FederationSearchResultUnion = Post | User\n\ntype Post @key(fields: "id") {\n  id: ID!\n  title: String!\n  authorId: Int!\n}\n\ntype Query {\n  findPost(id: Float!): Post!\n  getPosts: [Post!]!\n  search: [FederationSearchResultUnion!]! @deprecated(reason: "test")\n}\n\ntype User @extends @key(fields: "id") {\n  id: ID! @external\n  posts: [Post!]!\n}\n',
+      },
+    });
   });
 
-  it('should return the search result', () => {
-    return request(app.getHttpServer())
-      .post('/graphql')
-      .send({
-        operationName: null,
-        variables: {},
-        query: `
+  it('should return the search result', async () => {
+    const response = await apolloClient.query({
+      query: gql`
         {
           search {
             ... on Post {
@@ -53,22 +50,21 @@ describe('Code-first - Federation', () => {
             }
             __typename
           }
-        }`,
-      })
-      .expect(200, {
-        data: {
-          search: [
-            {
-              id: '1',
-              __typename: 'User',
-            },
-            {
-              title: 'lorem ipsum',
-              __typename: 'Post',
-            },
-          ],
+        }
+      `,
+    });
+    expect(response.data).toEqual({
+      search: [
+        {
+          id: '1',
+          __typename: 'User',
+        },
+        {
+          title: 'lorem ipsum',
+          __typename: 'Post',
         },
-      });
+      ],
+    });
   });
 
   afterEach(async () => {