Discord.js delete every channel in a guild

delete_channels.js

const Discord = require('discord.js');
const client = new Discord.Client();

client.once('ready', () => {
	console.log('Ready!');
	var server = client.guilds.get('Server ID here');
	for (var i = 0; i < server.channels.array().length; i++) {
    	server.channels.array()[i].delete();
	}
	console.log('Done!');
});

client.login('Token ID here');