Add event for dev process stop (#42255)

x-ref: [slack
thread](https://vercel.slack.com/archives/C02HEJASXGD/p1667173179573409?thread_ts=1667165920.338789&channel=C02HEJASXGD&message_ts=1667173179.573409)

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

packages/next/bin/next.ts

@@ -113,7 +113,7 @@ if (process.versions.pnp === '3') {
 
 // 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) {
+if (!process.env.NEXT_MANUAL_SIG_HANDLE && command !== 'dev') {
   process.on('SIGTERM', () => process.exit(0))
   process.on('SIGINT', () => process.exit(0))
 }

packages/next/cli/next-dev.ts

@@ -11,9 +11,39 @@ import { getProjectDir } from '../lib/get-project-dir'
 import { CONFIG_FILES } from '../shared/lib/constants'
 import path from 'path'
 import type { NextConfig } from '../types'
-import { interopDefault } from '../lib/interop-default'
-import { Telemetry } from '../telemetry/storage'
-import { NextConfigComplete } from '../server/config-shared'
+import type { NextConfigComplete } from '../server/config-shared'
+import { traceGlobals } from '../trace/shared'
+
+let isTurboSession = false
+let sessionStopHandled = false
+let sessionStarted = Date.now()
+
+const handleSessionStop = async () => {
+  if (sessionStopHandled) return
+  sessionStopHandled = true
+
+  const { eventCliSession } =
+    require('../telemetry/events/session-stopped') as typeof import('../telemetry/events/session-stopped')
+  const telemetry = traceGlobals.get('telemetry') as InstanceType<
+    typeof import('../telemetry/storage').Telemetry
+  >
+  if (!telemetry) {
+    process.exit(0)
+  }
+
+  telemetry.record(
+    eventCliSession({
+      cliCommand: 'dev',
+      turboFlag: isTurboSession,
+      durationMilliseconds: Date.now() - sessionStarted,
+    })
+  )
+  await telemetry.flush()
+  process.exit(0)
+}
+
+process.on('SIGINT', handleSessionStop)
+process.on('SIGTERM', handleSessionStop)
 
 const nextDev: cliCommand = (argv) => {
   const validArgs: arg.Spec = {
@@ -105,6 +135,7 @@ const nextDev: cliCommand = (argv) => {
   }
 
   if (args['--turbo']) {
+    isTurboSession = true
     // check for postcss, babelrc, swc plugins
     return new Promise<void>(async (resolve) => {
       const { findConfigPath } =
@@ -127,6 +158,11 @@ const nextDev: cliCommand = (argv) => {
         require('../telemetry/events/version') as typeof import('../telemetry/events/version')
       const { findPagesDir } =
         require('../lib/find-pages-dir') as typeof import('../lib/find-pages-dir')
+      const { interopDefault } =
+        require('../lib/interop-default') as typeof import('../lib/interop-default')
+      const { setGlobal } = require('../trace') as typeof import('../trace')
+      const { Telemetry } =
+        require('../telemetry/storage') as typeof import('../telemetry/storage')
 
       // To regenerate the TURBOPACK gradient require('gradient-string')('blue', 'red')('>>> TURBOPACK')
       const isTTY = process.stdout.isTTY
@@ -293,6 +329,7 @@ If you cannot make the changes above, but still want to try out\nNext.js v13 wit
           const telemetry = new Telemetry({
             distDir,
           })
+          setGlobal('telemetry', telemetry)
 
           telemetry.record(
             eventCliSession(distDir, rawNextConfig as NextConfigComplete, {

packages/next/telemetry/events/session-stopped.ts

@@ -0,0 +1,31 @@
+const EVENT_VERSION = 'NEXT_CLI_SESSION_STOPPED'
+
+export type EventCliSessionStopped = {
+  cliCommand: string
+  nextVersion: string
+  nodeVersion: string
+  turboFlag?: boolean | null
+  durationMilliseconds?: number | null
+}
+
+export function eventCliSession(
+  event: Omit<EventCliSessionStopped, 'nextVersion' | 'nodeVersion'>
+): { eventName: string; payload: EventCliSessionStopped }[] {
+  // This should be an invariant, if it fails our build tooling is broken.
+  if (typeof process.env.__NEXT_VERSION !== 'string') {
+    return []
+  }
+
+  const payload: EventCliSessionStopped = {
+    nextVersion: process.env.__NEXT_VERSION,
+    nodeVersion: process.version,
+    cliCommand: event.cliCommand,
+    durationMilliseconds: event.durationMilliseconds,
+    ...(typeof event.turboFlag !== 'undefined'
+      ? {
+          turboFlag: !!event.turboFlag,
+        }
+      : {}),
+  }
+  return [{ eventName: EVENT_VERSION, payload }]
+}

test/integration/telemetry/test/index.test.js

@@ -10,6 +10,7 @@ import {
   waitFor,
   nextBuild,
   nextLint,
+  check,
 } from 'next-test-utils'
 
 const appDir = path.join(__dirname, '..')
@@ -394,6 +395,61 @@ describe('Telemetry CLI', () => {
     expect(event1).toMatch(/"turboFlag": true/)
   })
 
+  it('detects --turbo correctly for `next dev` stopped', async () => {
+    let port = await findPort()
+    let stderr = ''
+
+    const handleStderr = (msg) => {
+      stderr += msg
+    }
+    let app = await launchApp(appDir, port, {
+      onStderr: handleStderr,
+      env: {
+        NEXT_TELEMETRY_DEBUG: 1,
+      },
+      turbo: true,
+    })
+
+    if (app) {
+      await killApp(app)
+    }
+    await check(() => stderr, /NEXT_CLI_SESSION_STOPPED/)
+
+    const event1 = /NEXT_CLI_SESSION_STOPPED[\s\S]+?{([\s\S]+?)}/
+      .exec(stderr)
+      .pop()
+
+    expect(event1).toMatch(/"turboFlag": true/)
+  })
+
+  it('detects correctly for `next dev` stopped (no turbo)', async () => {
+    let port = await findPort()
+    let stderr = ''
+
+    const handleStderr = (msg) => {
+      stderr += msg
+    }
+    let app = await launchApp(appDir, port, {
+      onStderr: handleStderr,
+      env: {
+        NEXT_TELEMETRY_DEBUG: 1,
+      },
+    })
+
+    await check(() => stderr, /NEXT_CLI_SESSION_STARTED/)
+
+    if (app) {
+      await killApp(app)
+    }
+    await check(() => stderr, /NEXT_CLI_SESSION_STOPPED/)
+
+    const event1 = /NEXT_CLI_SESSION_STOPPED[\s\S]+?{([\s\S]+?)}/
+      .exec(stderr)
+      .pop()
+
+    expect(event1).toMatch(/"turboFlag": false/)
+  })
+
   it('detect reportWebVitals correctly for `next build`', async () => {
     // Case 1: When _app.js does not exist.
     let build = await nextBuild(appDir, [], {