each-async

Async concurrent iterator (async forEach)

I often use async.each() for doing async operations when iterating, but I almost never use the other gadzillion methods in async.

Async iteration is one of the most used async control flow patterns.

I would strongly recommend using promises instead. You could then use the built-in Promise.all(), or p-map if you need concurrency control.

Install

$ npm install --save each-async

Usage

const eachAsync = require('each-async');

eachAsync(['foo','bar','baz'], (item, index, done) => {
	console.log(item, index);
	done();
}, error => {
	console.log('finished');
});
//=> 'foo 0'
//=> 'bar 1'
//=> 'baz 2'
//=> 'finished'

API

eachAsync(input, callback, [finishedCallback])

input

Type: Array

Array you want to iterate.

callback(item, index, done)

Type: Function

Called for each item in the array with the following arguments:

item: the current item in the array
index: the current index
done([error]): call this when you're done with an optional error. Supplying anything other than undefined/null will stop the iteration.

Note that order is not guaranteed since each item is handled concurrently.

finishedCallback(error)

Type: Function

Called when the iteration is finished or on the first error. First argument is the error passed from done() in the callback.