Close-with-grace NPM

close-with-grace

Exit your process, gracefully (if possible) - for Node.js

Install

npm i close-with-grace

Usage

const closeWithGrace = require('close-with-grace')

// delay is the number of milliseconds for the graceful close to
// finish.
closeWithGrace({ delay: 500 }, async function ({ signal, err, manual }) {
  if (err) {
    console.error(err)
  }
  await closeYourServer()
})

// default delay is 10000
// to disable delay feature at all, pass falsy value to delay option.
closeWithGrace({ delay: false }, () => await somethingUseful())

Injecting custom logger

const closeWithGrace = require('close-with-grace')

// delay is the number of milliseconds for the graceful close to
// finish.
closeWithGrace(
  {
    delay: 500,
    logger: { error: (m) => console.error(`[close-with-grace] ${m}`) }
  },
  async function ({ signal, err, manual }) {
  if (err) {
    console.error(err)
  }
  await closeYourServer()
})

// default logger is console
// to disable logging at all, pass falsy value to logger option.
closeWithGrace({ logger: false }, () => await somethingUseful())

Example with Fastify

import fastify from 'fastify'
import closeWithGrace from 'close-with-grace'

const app = fastify()

closeWithGrace(async function ({ signal, err, manual }) {
  if (err) {
    app.log.error({ err }, 'server closing with error')
  } else {
    app.log.info(`${signal} received, server closing`)
  }
  await app.close()
})

await app.listen()

API

`closeWithGrace([opts], fn({ err, signal, manual }))`

closeWithGrace adds a global listeners to the events:

process.once('SIGHUP')
process.once('SIGINT')
process.once('SIGQUIT')
process.once('SIGILL')
process.once('SIGTRAP')
process.once('SIGABRT')
process.once('SIGBUS')
process.once('SIGFPE')
process.once('SIGSEGV')
process.once('SIGUSR2')
process.once('SIGTERM')
process.once('uncaughtException')
process.once('unhandledRejection')
process.once('beforeExit')

In case one of them is emitted, it will call the given function. If it is emitted again, it will terminate the process abruptly.

opts

delay: the numbers of milliseconds before abruptly close the process. Default: 10000.
- Pass false, null or undefined to disable this feature.
logger: instance of logger which will be used internally. Default: console.
- Pass false, null or undefined to disable this feature.

fn({ err, signal, manual } , cb)

Execute the given function to perform a graceful close. The function can either return a Promise or call the callback. If this function does not error, the process will be closed with exit code 0. If the function rejects with an Error, or call the callback with an Error as first argument, the process will be closed with exit code 1.