upgrade to apollo server 4

package.json

@@ -26,7 +26,7 @@
     "update": "npx npm-check-update"
   },
   "dependencies": {
-    "apollo-server-express": "^3.13.0",
+    "@apollo/server": "^4.9.5",
     "graphql": "^16.8.1",
     "graphql-scalars": "^1.22.4",
     "reflect-metadata": "^0.1.13",
@@ -34,7 +34,6 @@
   },
   "devDependencies": {
     "@eslint-community/eslint-plugin-eslint-comments": "^4.1.0",
-    "@types/express": "^4.17.21",
     "@types/jest": "^29.5.10",
     "@types/node": "^20.10.1",
     "@typescript-eslint/eslint-plugin": "^6.13.1",
@@ -66,7 +65,8 @@
   },
   "imports": {
     "#graphql/*": "./src/graphql/*",
-    "#types/*": "./src/graphql/types/*",
-    "#test/*": "./test/*"
+    "#src/*": "./src/*",
+    "#test/*": "./test/*",
+    "#types/*": "./src/graphql/types/*"
   }
 }

src/graphql/resolvers/HelloResolver.spec.ts

@@ -1,20 +1,25 @@
-import { ApolloServerTestClient } from 'apollo-server-testing'
+import { ApolloServer } from '@apollo/server'
 
-import { testEnvironment } from '#test/helpers'
+import { createServer } from '#src/server/server'
 
-let query: ApolloServerTestClient['query']
+let testServer: ApolloServer
 
 beforeAll(async () => {
-  const testEnv = await testEnvironment()
-  query = testEnv.query
+  testServer = await createServer()
 })
 
 describe('HelloResolver', () => {
   it('return "Hello World!"', async () => {
-    await expect(query({ query: '{ hello { hello } }' })).resolves.toMatchObject({
-      data: {
-        hello: {
-          hello: 'Hello world!',
+    const response = await testServer.executeOperation({
+      query: '{ hello { hello } }',
+    })
+    expect(response.body).toMatchObject({
+      kind: 'single',
+      singleResult: {
+        data: {
+          hello: {
+            hello: 'Hello world!',
+          },
         },
       },
     })

src/graphql/schema.ts

@@ -1,5 +1,3 @@
-import path from 'path'
-
 import { GraphQLSchema } from 'graphql'
 import { buildSchema } from 'type-graphql'
 

src/index.ts

@@ -3,9 +3,9 @@ import 'reflect-metadata'
 import { listen } from './server/server'
 
 export async function main() {
-  await listen(4000)
+  const url = await listen(4000)
   // eslint-disable-next-line no-console
-  console.log('🚀 Server is ready at http://localhost:4000/graphql')
+  console.log(`🚀 Server is ready at ${url}`)
 }
 
 main().catch((e) => {

src/server/server.spec.ts

@@ -1,24 +1,20 @@
-// eslint-disable-next-line @typescript-eslint/no-unused-vars
-import { ApolloServer } from 'apollo-server-express'
-import express from 'express'
+import { startStandaloneServer } from '@apollo/server/standalone'
 
 import { listen } from './server'
 
-jest.mock('express', () => {
-  const originalModule = jest.requireActual('express')
+jest.mock('@apollo/server/standalone', () => {
+  const originalModule = jest.requireActual('@apollo/server/standalone')
   return {
     __esModule: true,
     ...originalModule,
-    default: jest.fn(() => {
+    startStandaloneServer: jest.fn(() => {
       return {
-        listen: jest.fn(),
+        url: 'url',
       }
     }),
   }
 })
 
-jest.mock('apollo-server-express')
-
 describe('server', () => {
   describe('listen', () => {
     beforeEach(async () => {
@@ -26,8 +22,8 @@ describe('server', () => {
       await listen(4000)
     })
 
-    it('calls express', () => {
-      expect(express).toBeCalled()
+    it('calls startStandaloneServer', () => {
+      expect(startStandaloneServer).toBeCalled()
     })
   })
 })

src/server/server.ts

@@ -1,18 +1,18 @@
-import { ApolloServer } from 'apollo-server-express'
-import express from 'express'
+import { ApolloServer } from '@apollo/server'
+import { startStandaloneServer } from '@apollo/server/standalone'
 
 import { schema } from '#graphql/schema'
 
-export async function listen(port: number) {
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const app: any = express()
-
-  const server = new ApolloServer({
+export const createServer = async (): Promise<ApolloServer> => {
+  return new ApolloServer({
     schema: await schema(),
   })
-  await server.start()
-
-  server.applyMiddleware({ app, path: '/' })
-
-  return app.listen(port)
+}
+
+export async function listen(port: number) {
+  const { url } = await startStandaloneServer(await createServer(), {
+    listen: { port },
+  })
+
+  return url
 }

test/helpers.ts

@@ -1,12 +0,0 @@
-import { ApolloServer } from 'apollo-server-express'
-import { createTestClient } from 'apollo-server-testing'
-
-import { schema } from '#graphql/schema'
-
-export const testEnvironment = async () => {
-  const server = new ApolloServer({
-    schema: await schema(),
-  })
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  return createTestClient(server as any)
-}

tsconfig.json

@@ -9,8 +9,9 @@
     "lib": ["ESNext"],
     "paths": {
       "#graphql/*": ["./src/graphql/*"],
-      "#types/*": ["./src/graphql/types/*"],
-      "#test/*": ["./test/*"]
+      "#src/*": ["./src/*"],
+      "#test/*": ["./test/*"],
+      "#types/*": ["./src/graphql/types/*"]
     },
     "outDir": "./build/src",
     "esModuleInterop": true,