lukeed/worktop.cache-kv.ts

## worktop.cache-kv.ts
import { Router } from 'worktop';
import * as Cache from 'worktop/cache';
import { read, write } from 'worktop/kv';

import type { Method } from 'worktop/request';
import type { Handler } from 'worktop';
import type { KV } from 'worktop/kv';

// KV Namespace Binding
declare const SAVED: KV.Namespace;

const API = new Router;

interface Head {
	status: number;
	headers: Record<string, string>;
}

// Custom utility method
// Write the generated `Response` into KV
const persist: Handler = async function (req, res) {
	await write<Head>(SAVED, `${req.method}::${req.url}::head`, {
		headers: res.getHeaders(),
		status: res.status,
	});

	if (!isBodyless(req.method, res.status)) {
		await write(SAVED, `${req.method}::${req.url}::body`, res.body);
	}
}

function isBodyless(method: Method, status: number) {
	return (method === 'HEAD' || status === 101 || status === 204 || status === 205 || status === 304);
}

// Cache MISS, so check KV now
// NOTE: Runs before any (and all) routing
API.prepare = async function (req, res) {
	let head = await read<Head>(SAVED, `${req.method}::${req.url}::head`, 'json');
	if (!head) return; // stop here, had no match

	let { status, headers } = head;
	let body = isBodyless(req.method, status) ? null
		: await read<ArrayBuffer>(SAVED, `${req.method}::${req.url}::body`, 'arrayBuffer');

	return new Response(body, { status, headers });
}

// Every/Any route handler
// Cache MISS && KV does not exist
API.add('GET', '/foo/:name', async (req, res) => {
	let data = await fetch('...something...');

	res.setHeader('Cache-Control', 'public,max-age=3600');
	res.body = await data.text();
	res.status = 201;

	return persist(req, res);
});

// Every/Any route handler
// Cache MISS && KV does not exist
API.add('GET', '/hello/:world', (req, res) => {
	// NOTE: Can still use response helpers
	res.send(201, `hello, ${req.params.world}`)
	// ~> just send everything thru persist
	return persist(req, res);
});

// Init & hookup to Cache API
Cache.listen(API.run);
	import { Router } from 'worktop';
	import * as Cache from 'worktop/cache';
	import { read, write } from 'worktop/kv';

	import type { Method } from 'worktop/request';
	import type { Handler } from 'worktop';
	import type { KV } from 'worktop/kv';

	// KV Namespace Binding
	declare const SAVED: KV.Namespace;

	const API = new Router;

	interface Head {
	status: number;
	headers: Record<string, string>;
	}

	// Custom utility method
	// Write the generated `Response` into KV
	const persist: Handler = async function (req, res) {
	await write<Head>(SAVED, `${req.method}::${req.url}::head`, {
	headers: res.getHeaders(),
	status: res.status,
	});

	if (!isBodyless(req.method, res.status)) {
	await write(SAVED, `${req.method}::${req.url}::body`, res.body);
	}
	}

	function isBodyless(method: Method, status: number) {
	return (method === 'HEAD' \|\| status === 101 \|\| status === 204 \|\| status === 205 \|\| status === 304);
	}

	// Cache MISS, so check KV now
	// NOTE: Runs before any (and all) routing
	API.prepare = async function (req, res) {
	let head = await read<Head>(SAVED, `${req.method}::${req.url}::head`, 'json');
	if (!head) return; // stop here, had no match

	let { status, headers } = head;
	let body = isBodyless(req.method, status) ? null
	: await read<ArrayBuffer>(SAVED, `${req.method}::${req.url}::body`, 'arrayBuffer');

	return new Response(body, { status, headers });
	}

	// Every/Any route handler
	// Cache MISS && KV does not exist
	API.add('GET', '/foo/:name', async (req, res) => {
	let data = await fetch('...something...');

	res.setHeader('Cache-Control', 'public,max-age=3600');
	res.body = await data.text();
	res.status = 201;

	return persist(req, res);
	});

	// Every/Any route handler
	// Cache MISS && KV does not exist
	API.add('GET', '/hello/:world', (req, res) => {
	// NOTE: Can still use response helpers
	res.send(201, `hello, ${req.params.world}`)
	// ~> just send everything thru persist
	return persist(req, res);
	});

	// Init & hookup to Cache API
	Cache.listen(API.run);