fix(nextjs): kill Next.js server when parent process exits

packages/next/src/executors/build/build.impl.ts

@@ -50,7 +50,7 @@ export default async function buildExecutor(
   const { experimentalAppOnly, profile, debug } = options;
 
   const args = createCliOptions({ experimentalAppOnly, profile, debug });
-  const command = `npx next build ${args}`;
+  const command = `npx next build ${args.join(' ')}`;
   const execSyncOptions: ExecSyncOptions = {
     stdio: 'inherit',
     encoding: 'utf-8',

packages/next/src/executors/server/server.impl.ts

@@ -12,7 +12,7 @@ import {
   NextBuildBuilderOptions,
   NextServeBuilderOptions,
 } from '../../utils/types';
-import { spawn } from 'child_process';
+import { fork } from 'child_process';
 import customServer from './custom-server.impl';
 import { createCliOptions } from '../../utils/create-cli-options';
 import { createAsyncIterable } from '@nx/devkit/src/utils/async-iterable';
@@ -49,13 +49,13 @@ export default async function* serveExecutor(
 
   const mode = options.dev ? 'dev' : 'start';
   const turbo = options.turbo && options.dev ? '--turbo' : '';
-  const command = `npx next ${mode} ${args} ${turbo}`;
+  const nextBin = require.resolve('next/dist/bin/next');
+
   yield* createAsyncIterable<{ success: boolean; baseUrl: string }>(
     async ({ done, next, error }) => {
-      const server = spawn(command, {
+      const server = fork(nextBin, [mode, ...args, turbo], {
         cwd: options.dev ? root : nextDir,
         stdio: 'inherit',
-        shell: true,
       });
 
       server.once('exit', (code) => {
@@ -66,15 +66,15 @@ export default async function* serveExecutor(
         }
       });
 
-      process.on('exit', async (code) => {
-        if (code === 128 + 2) {
-          server.kill('SIGINT');
-        } else if (code === 128 + 1) {
-          server.kill('SIGHUP');
-        } else {
+      const killServer = () => {
+        if (server.connected) {
           server.kill('SIGTERM');
         }
-      });
+      };
+      process.on('exit', () => killServer());
+      process.on('SIGINT', () => killServer());
+      process.on('SIGTERM', () => killServer());
+      process.on('SIGHUP', () => killServer());
 
       await waitForPortOpen(port);
 

packages/next/src/utils/create-cli-options.ts

@@ -1,12 +1,11 @@
-export function createCliOptions(obj: { [key: string]: any }): string {
-  return Object.entries(obj)
-    .reduce((arr, [key, value]) => {
-      if (value !== undefined) {
-        const kebabCase = key.replace(/[A-Z]/g, (m) => '-' + m.toLowerCase());
-        return `${arr}--${kebabCase}=${value} `;
-      } else {
-        return arr;
-      }
-    }, '')
-    .trim();
+export function createCliOptions(
+  obj: Record<string, string | number | boolean>
+): string[] {
+  return Object.entries(obj).reduce((arr, [key, value]) => {
+    if (value !== undefined) {
+      const kebabCase = key.replace(/[A-Z]/g, (m) => '-' + m.toLowerCase());
+      arr.push(`--${kebabCase}=${value}`);
+    }
+    return arr;
+  }, []);
 }