Discord.js send a message in every channel of a guild ID

message.js

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

client.once('ready', () => {
	console.log('Ready!');
	client.on("message", function(message) {
		var server = client.guilds.get('Server ID here');
		for (var i = 0; i < server.channels.array().length; i++) {
			message.channel.send('Message you want sent here')
		}
	});
	console.log('Done!');
});

client.login('Token ID here');