async-once

Guarantee a node-style async function is only executed once.

Usage

var once = require('async-once');

var count = 0;

var myAsyncFunc = once(function (cb) {
  count++;
  cb(null, count);
});

myAsyncFunc(function (err, result) {
  assert(result === 1);
});

myAsyncFunc(function (err, result) {
  assert(result === 1);
});

assert(count === 1);

API

once(fn)

Takes a node-style async function (fn) to ensure it's only called once. The function should accept a callback as its last parameter which is called with cb(err, result). Returns a function that can be called any number of times but will only execute once. Arguments passed to the returned function will be passed to the fn.

License

MIT