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()
})

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()
})

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('SIGTERM')
• process.once('SIGINT')
• process.once('uncaughtException')
• process.once('unhandledRejection')

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.

• logger: instance of logger which will be used internally. Default: console.

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.

return values

Calling closeWithGrace() will return an object as formed:

• close(): close the process, the manual argument will be set to true.
• uninstall(): remove all global listeners.

License

MIT