Facets

This example starts a Worker at runtime with the Worker Loader, and it runs a Durable Object class from that Worker as a facet of a Durable Object. The facet counts the requests in its own SQLite database with the synchronous KV API, and celld replicates that database with the root object. The parent passes a parameterized ctx.exports Service Binding through WorkerCode.env, so the loaded Worker can call the parent entrypoint.

The worker_loaders key of wrangler.jsonc declares the Worker Loader, and the entry in this example puts the binding at env.LOADER. Cloudflare can still change the Worker Loader API, so this example needs no setting but it can change. Start the example:

celld dev .
curl http://127.0.0.1:9876/

Each request answers the count and the parent entrypoint's greeting. The count survives a restart of the command.