NodeJS Async function help!

[Munzy]

Alright, so I am new to nodejs from php. As most know, php being linear/blocking made coding *easy* per-say. However, I have found myself loving nodejs, and I am having a hard time wrapping my mind around how to let a nodejs function run async, but then wait for responses of that async function before continuing.


Here is some example code


var ping = require("ping");

var verHosts = [
'192.168.230.118',
'192.168.230.25'
];

var verStatus = 0;

verHosts.forEach(function(host) {
ping.sys.probe(host, function(isAlive){
if(isAlive == true) {
verStatus++;
}
})
});
console.log(Date() + " " + "Verified status is at: " + verStatus);
if(verStatus > 0) { // continue shiz and giggles here after I get the above};




If you could elaborate as I am trying to learn as well, not just copy paste in dummy mode!


Thanks!

 

[joepie91]

Basically, you'd use Promises. Any kind of looping or conditional asynchronous work is very hard to get right with callbacks alone.


I've put together a reading list about Promises here, that should get you started - Promise.map is most likely what you're looking for in particular