fix(api): cleaner exits before respawn (#66135)

api/src/app.ts

@@ -41,6 +41,7 @@ import {
   FCC_ENABLE_SWAGGER_UI,
   FCC_ENABLE_SHADOW_CAPTURE,
   FCC_ENABLE_SENTRY_ROUTES,
+  FREECODECAMP_NODE_ENV,
   GROWTHBOOK_FASTIFY_API_HOST,
   GROWTHBOOK_FASTIFY_CLIENT_KEY
 } from './utils/env.js';
@@ -86,7 +87,11 @@ export const buildOptions: FastifyHttpOptions<
   loggerInstance: getLogger(),
   genReqId: () => randomBytes(8).toString('hex'),
   // disabled so we can customise the request/response logging
-  disableRequestLogging: true
+  disableRequestLogging: true,
+  // destroy all connections on close to avoid EADDRINUSE
+  // on restart, in development. Leave default in production.
+  forceCloseConnections:
+    FREECODECAMP_NODE_ENV === 'production' ? ('idle' as const) : true
 };
 
 /**

api/src/server.ts

@@ -8,8 +8,17 @@ const start = async () => {
 
   const stop = async (signal: NodeJS.Signals) => {
     fastify.log.info(`Received ${signal}, shutting down.`);
+
+    fastify.server.closeAllConnections();
+    await new Promise<void>(resolve => {
+      fastify.server.close(() => resolve());
+    });
+
+    // Yield one tick so libuv can finalize uv_close() on the TCP handle
+    // before pino's autoEnd blocks the event loop via Atomics.wait().
+    await new Promise<void>(resolve => setImmediate(resolve));
+
     await fastify.close();
-    fastify.log.info('Shutdown complete');
     process.exit(0);
   };
 
@@ -17,9 +26,7 @@ const start = async () => {
   process.on('SIGTERM', signal => void stop(signal));
 
   try {
-    const port = Number(PORT);
-    fastify.log.info(`Starting server on port ${port}`);
-    await fastify.listen({ port, host: HOST });
+    await fastify.listen({ port: Number(PORT), host: HOST });
   } catch (err) {
     fastify.log.error(err);
     process.exit(1);