Delete messages from users that left your server

deleteMessages.js

async function clearMessages(server, channel, author, offset=0) {
	const authToken = 'YOUR_DISCORD_TOKEN';
	const headers = { 'Authorization': authToken, 'Content-Type': 'application/json' };
	const baseURL = `https://discordapp.com/api/v6/channels`;
	let searchURL = `https://discordapp.com/api/v6/guilds/${server}/messages/search?channel_id=${channel}&offset=${offset}&include_nsfw=true`;

	let clock = 0;
	let interval = 2000;
	function delay(duration) {
		return new Promise((resolve, reject) => {
			setTimeout(() => resolve(), duration);
		});
	}

	const response = await fetch(searchURL, {headers});
	const json = await response.json();
    if (json.retry_after) return delay(json.retry_after).then(() => clearMessages(server, channel, author, offset));
    const messages = [].concat.apply([], json.messages).filter(m => m.hit == true && m.author.id == author)
	console.log("There are " + messages.length + " messages left to delete.");
    console.log(messages, json, offset)
	await messages.forEach(async function(item) {
		if(item.hit == true && item.author.id == author) {
			await delay(clock += interval);
			await fetch(`${baseURL}/${item.channel_id}/messages/${item.id}`, { headers, method: 'DELETE' });
	    }
	});

	if (offset < json.total_results) { 
		delay(clock += interval).then(() => clearMessages(server, channel, author, offset+json.messages.length));
	} else {
		console.log("Finished deleting messages")
	};
}