Close http server in cleanup

[Meemaw]

Verify canary release

• I verified that the issue exists in the latest Next.js canary release

Provide environment information

    Operating System:
      Platform: darwin
      Arch: arm64
      Version: Darwin Kernel Version 22.5.0: Thu Jun  8 22:22:20 PDT 2023; root:xnu-8796.121.3~7/RELEASE_ARM64_T6000
    Binaries:
      Node: 20.3.1
      npm: 9.6.7
      Yarn: 1.22.18
      pnpm: 7.29.3
    Relevant Packages:
      next: 13.4.13-canary.18
      eslint-config-next: N/A
      react: 18.2.0
      react-dom: 18.2.0
      typescript: 5.1.3
    Next.js Config:
      output: N/A

Which area(s) of Next.js are affected? (leave empty if unsure)

Standalone mode (output: "standalone")

Link to the code that reproduces this issue or a replay of the bug

https://github.com/Meemaw/next-server-shutdown-reproducer

To Reproduce

1. yarn build
2. yarn start
3. Visit http://localhost:3000
4. Close the server before the page renders
5. Get a "This site can’t be reached" error

Describe the Bug

NextJS doesn't gracefully handle inflight HTTP server connections. There is a cleanup code

next.js/packages/next/src/server/lib/start-server.ts

Line 262 in 498692b

const cleanup = () => {

, but it doesn't call server.cleanup().

There also seems to be a teardown function defined

next.js/packages/next/src/server/lib/start-server.ts

Line 500 in 498692b

async function teardown() {

)

, which does the correct thing, but is never called?

Expected Behavior

server.cleanup() should be called & awaited so any inflight requests are gracefully handled.

Which browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response

_NEXT-1961

[redbmk]

It looks like the code has change a bit but the issue is still there. To add to this, it looks like the standalone server.js file that gets generated has it's own conflicting code that immediately kills the server.

next.js/packages/next/src/build/utils.ts

Lines 2029 to 2034 in e975717

	// Make sure commands gracefully respect termination signals (e.g. from Docker)
	// Allow the graceful termination to be manually configurable
	if (!process.env.NEXT_MANUAL_SIG_HANDLE) {
	process.on('SIGTERM', () => process.exit(0))
	process.on('SIGINT', () => process.exit(0))
	}

next.js/packages/next/src/server/lib/start-server.ts

Lines 283 to 287 in e975717

	if (!process.env.NEXT_MANUAL_SIG_HANDLE) {
	// callback value is signal string, exit with 0
	process.on('SIGINT', () => cleanup(0))
	process.on('SIGTERM', () => cleanup(0))
	}

So as I understand this, the standalone server.js will run process.exit(0) unless you have the NEXT_MANUAL_SIG_HANDLE flag set, but then it calls startServer which will run server.close and then process.exit unless you set the same variable.

I would think since start-server has this code, we actually shouldn't have it in server.js