smile :)

A last-mile session cache for Cloudflare Workers

Smile is a private HTTP cache implemented on Durable Objects. It brings your application's data close to the user to make repeated requests super-fast. It uses stale-while-revalidate caching by default when no Cache-Control directives are present in the request or response.

Installation

pnpm add @cloudflare/smile

Usage

Include a new migration and Durable Object binding to Smile in your wrangler.toml:

[[migrations]]
tag = "v1"
new_sqlite_classes = ["Smile"]

[[durable_objects.bindings]]
name = "SMILE"
class_name = "Smile"

Then get a stub to an instance of Smile inside of your Worker. Caches are scoped by the ID you use to instantiate your Durable Object, so it's recommended to use a session ID coming from the request. Then, simply fetch through your Smile instance and enjoy faster response times.

// worker.js

export { Smile } from '@cloudflare/smile'; // re-export the Durable Object class so it gets included in your Worker bundle

export default {
	fetch(request, env, ctx) {
		const sessionId = request.headers.get('x-session-id'); // In practice, you'll probably get the session ID from a cookie

		const cacheId = env.SMILE.idFromName(sessionId);
		const smile = env.SMILE.get(cacheId);

		return smile.fetch(request);
	},
};