Pinging domains

I'd like to cycle through a list of ~90 domains to ping for the lowest response time, however the ESP8266.ping function only allows IP Addresses, so whats the best way to convert the URLs into direct IP Addresses?

URL to IP address is usually done by a DNS server.
https://en.wikipedia.org/wiki/Domain_Name_System

For IOT devices you may need to set up a local DNS for them.

https://en.wikipedia.org/wiki/BIND
https://www.isc.org/downloads/bind/
http://www.zytrax.com/books/dns/
Your router may need to add the local DNS server to its list of DNS servers.

See the DNS references on this page to register a device's IP with the DNS.
http://www.espruino.com/ESP8266_WifiUsage

Thanks but in the end I just created a Ping Module, I've created a pull request here which does include documentation but its really simple to use, all you gotta do is:

var p = require("Ping");

p.ping({ address: 'google.com' }, function(err, data) {
  console.log(data);
});

to get :

{
  "address": "google.com",
  "port": 80, "attempts": 5, "avg": 36.86366081237, "max": 54.41212654113, "min": 29.13498878479,
  "raw": [ 29.13498878479, 54.41212654113, 34.74617004394, 32.61685371398, 33.40816497802 ]
 }

where did this get added to the api? net.ping?? this is not the same as Wifi.ping.

It has been merged into modules

https://www.espruino.com/Ping