I am developing a backend API using Cloudflare Workers to cache the tokens into respective individual pages, something like http://cache.api/[tokenId] with token value itself as body content, using Cache API.
const tokenId = 'fakeJWT';
const internalUrl = ''.concat(
'http://cache.api/',
tokenId // the query string
);
const cacheUrl = new URL(internalUrl);
const cacheKey = new Request(cacheUrl.toString());
const cache = caches.default;
let response = new Response(tokenId);
response.headers.append('Cache-Control', 's-maxage=86400'); // 24 hours
await cache.put(cacheKey, response.clone());
I've configured Cache-Control header with 24 hours expiry. Then, I wrote another API in the same Cloudflare Workers to check the existence of the cache, it exists after 10 minutes but does not exist after 15 minutes.
const internalUrl = ''.concat(
'http://cache.api/',
tokenId // the query string
);
const cacheUrl = new URL(internalUrl);
const cacheKey = new Request(cacheUrl.toString());
const cache = caches.default;
let response = await cache.match(cacheKey);
if (!response) {
console.log(
`Cache url for ${cacheUrl} is not present`
);
return unauthorised(`${pathName}: This user session has expired! cache url is ${cacheUrl}`);
}
else
{
let response = new Response(tokenId);
response.headers.append('Cache-Control', 's-maxage=86400'); // in seconds
await cache.put(cacheKey, response.clone());
}
Did I miss anything?
What may be happening is a cache miss rather than an expiration. When using Cloudflare for caching, you shouldn't expect caching to be guaranteed, in particular using the cache API the docs mention it being data-center specific (not propagated globally) -
https://developers.cloudflare.com/workers/runtime-apis/cache/#background
Caching should be mechanism for improving performance, but not relied upon for guaranteed storage in other words. If your use-case requires this, it would be better to use the Workers Key Value -
https://developers.cloudflare.com/workers/learning/how-kv-works/