feat: modernize implementation, support promises

example.js

@@ -2,19 +2,21 @@
 
 const fastify = require('fastify')({
  logger: {
- level: 'info',
+ level: 'debug',
  },
 })
 
+const wait = (ms) => new Promise((resolve) => setTimeout(resolve, ms))
+
 fastify.register(require('./')).after((err) => {
  if (err) {
  fastify.log.error(err)
  }
  // Register custom clean up handler
- fastify.gracefulShutdown((signal, cb) => {
- fastify.log?.info('Received signal to shutdown: %s', signal)
- cb()
- fastify.log?.info('Graceful shutdown complete')
+ fastify.gracefulShutdown(async (signal) => {
+ fastify.log?.info('received signal to shutdown: %s', signal)
+ await wait(3000)
+ fastify.log?.info('graceful shutdown complete')
  })
 })
 
@@ -34,11 +36,7 @@ const schema = {
 }
 
 fastify.get('/', schema, async function (req, reply) {
- await new Promise((resolve, reject) => {
- setTimeout(() => {
- resolve()
- }, 5000)
- })
+ await wait(3000)
  reply.send({ hello: 'world' })
 })
 

index.d.ts

@@ -7,7 +7,7 @@ type FastifyGracefulShutdownPlugin =
 declare module 'fastify' {
  interface FastifyInstance {
  gracefulShutdown(
- handler: (signal: string, next: (err?: Error) => void) => void,
+ handler: (signal: string) => Promise<void> | void,
  ): void
  }
 }

index.js

@@ -2,7 +2,6 @@
 
 const fp = require('fastify-plugin')
 const process = require('process')
-const parallel = require('fastparallel')()
 
 let registeredListeners = []
 
@@ -38,15 +37,12 @@ function fastifyGracefulShutdown(fastify, opts, next) {
  function completed(err, signal) {
  if (err) {
  logger.error?.({ err: err, signal: signal }, 'process terminated')
- // Avoid losing data
- logger.flush?.()
- handlerEventListener.exit(1)
  } else {
  logger.debug?.({ signal: signal }, 'process terminated')
- // Avoid losing data
- logger.flush?.()
- handlerEventListener.exit(0)
  }
+
+ logger.flush?.()
+ handlerEventListener.exit(err ? 1 : 0)
  }
 
  function terminateAfterTimeout(signal, timeout) {
@@ -59,8 +55,14 @@ function fastifyGracefulShutdown(fastify, opts, next) {
  }, timeout).unref()
  }
 
- function shutdown(signal) {
- parallel(null, handlers, signal, (err) => completed(err, signal))
+ async function shutdown(signal) {
+ await Promise.all(
+ handlers.map((handler) => {
+ return handler(signal)
+ }),
+ )
+ logger.debug?.({ signal: signal }, 'closing fastify server')
+ await fastify.close()
  }
 
  function addHandler(handler) {
@@ -72,18 +74,14 @@ function fastifyGracefulShutdown(fastify, opts, next) {
 
  fastify.decorate('gracefulShutdown', addHandler)
 
- // shutdown fastify
- addHandler((signal, cb) => {
- logger.debug?.({ signal: signal }, 'triggering close hook')
- fastify.close(cb)
- })
-
  // register handlers
  signals.forEach((signal) => {
  const listener = () => {
- terminateAfterTimeout(signal, timeout)
  logger.debug?.({ signal: signal }, 'received signal')
+ terminateAfterTimeout(signal, timeout)
  shutdown(signal)
+ .then(() => completed(null, signal))
+ .catch((err) => completed(err, signal))
  }
  registeredListeners.push({ signal, listener })
  handlerEventListener.once(signal, listener)

index.test-d.ts

@@ -11,4 +11,5 @@ app.register(plugin, {
 app.register(plugin, { timeout: 1 })
 app.register(plugin)
 
-app.gracefulShutdown((signal: string, next: () => void) => {})
+app.gracefulShutdown((signal: string) => {})
+app.gracefulShutdown(async (signal: string) => {})