test: add integration test for gateway module

package.json

@@ -12,7 +12,7 @@
     "publish:npm": "npm publish --access public",
     "prepublish:next": "npm run build",
     "publish:next": "npm publish --access public --tag next",
-    "test:integration": "jest --config ./tests/jest-e2e.json"
+    "test:integration": "jest --config ./tests/jest-e2e.json --runInBand"
   },
   "devDependencies": {
     "@nestjs/common": "6.10.14",

tests/e2e/graphql-gateway.spec.ts

@@ -0,0 +1,113 @@
+import { INestApplication } from '@nestjs/common';
+import { Test } from '@nestjs/testing';
+import * as request from 'supertest';
+import { AppModule as PostsModule } from '../graphql-federation/posts-service/federation-posts.module';
+import { AppModule as UsersModule } from '../graphql-federation/users-service/federation-users.module';
+import { AppModule as GatewayModule } from '../graphql-federation/gateway/gateway.module';
+
+describe('GraphQL', () => {
+  let postsApp: INestApplication;
+  let usersApp: INestApplication;
+  let gatewayApp: INestApplication;
+
+  beforeEach(async () => {
+    const usersModule = await Test.createTestingModule({
+      imports: [UsersModule],
+    }).compile();
+
+    usersApp = usersModule.createNestApplication();
+    await usersApp.listenAsync(3001);
+
+    const postsModule = await Test.createTestingModule({
+      imports: [PostsModule],
+    }).compile();
+
+    postsApp = postsModule.createNestApplication();
+    await postsApp.listenAsync(3002);
+
+    const gatewayModule = await Test.createTestingModule({
+      imports: [GatewayModule],
+    }).compile();
+
+    gatewayApp = gatewayModule.createNestApplication();
+    await gatewayApp.init();
+  });
+
+  it(`should run lookup across boundaries`, () => {
+    return request(gatewayApp.getHttpServer())
+      .post('/graphql')
+      .send({
+        operationName: null,
+        variables: {},
+        query: `
+        {
+          getPosts {
+            id,
+            title,
+            body,
+            user {
+              id,
+              name,
+            }
+          }
+        }`,
+      })
+      .expect(200, {
+        data: {
+          getPosts: [
+            {
+              id: '1',
+              title: 'Hello world',
+              body: 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
+              user: {
+                id: '5',
+                name: 'GraphQL',
+              },
+            },
+          ],
+        },
+      });
+  });
+
+  it(`should run reverse lookup across boundaries`, () => {
+    return request(gatewayApp.getHttpServer())
+      .post('/graphql')
+      .send({
+        operationName: null,
+        variables: {},
+        query: `
+        {
+          getUser(id: "5") {
+            id,
+            name,
+            posts {
+              id,
+              title,
+              body,
+            }
+          }
+        }`,
+      })
+      .expect(200, {
+        data: {
+          getUser: {
+            id: '5',
+            name: 'GraphQL',
+            posts: [
+              {
+                id: '1',
+                title: 'Hello world',
+                body: 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
+              },
+            ],
+          },
+        },
+      });
+  });
+
+  afterEach(async () => {
+    await postsApp.close();
+    await usersApp.close();
+    await gatewayApp.close();
+  });
+});

tests/graphql-federation/gateway/gateway.module.ts

@@ -0,0 +1,15 @@
+import { Module } from '@nestjs/common';
+import { GraphQLGatewayModule } from '../../../lib/graphql-gateway.module';
+import { join } from 'path';
+
+@Module({
+  imports: [
+    GraphQLGatewayModule.forRoot({
+      serviceList: [
+        { name: 'users', url: 'http://localhost:3001/graphql' },
+        { name: 'posts', url: 'http://localhost:3002/graphql' },
+      ],
+    }),
+  ],
+})
+export class AppModule {}