on-exit-leak-free

on-exit-leak-free

Execute a function on exit without leaking memory, allowing all objects to be garbage collected. Listen to both 'beforeExit' and 'exit, executing the given function only once.

Requires WeakRef, WeakMap and FinalizationRegistry, i.e. use Node v14+.

Install

npm i on-exit-leak-free

Example

'use strict'

const { register, unregister } = require('on-exit-leak-free')
const assert = require('assert')

function setup () {
  // This object can be safely garbage collected,
  // and the resulting shutdown function will not be called.
  // There are no leaks.
  const obj = { foo: 'bar' }
  register(obj, shutdown)
  // call unregister(obj) to remove
}

let shutdownCalled = false

// Please make sure that the function passed to register()
// does not create a closure around unnecessary objects.
function shutdown (obj, eventName) {
  console.log(eventName) // beforeExit
  shutdownCalled = true
  assert.strictEqual(obj.foo, 'bar')
}

setup()

process.on('exit', function () {
  assert.strictEqual(shutdownCalled, true)
})

License

MIT