TypeScript

The @cloudflare/workers-types ↗ package provides the Service and DurableObjectNamespace types, each of which accepts a single type parameter for the server-side WorkerEntrypoint or DurableObject types.

Using higher-order types, we automatically generate client-side stub types (e.g., forcing all methods to be async).

For example:

interface Env {
  SUM_SERVICE: Service<SumService>;
  COUNTER_OBJECT: DurableObjectNamespace<Counter>
}

export default {
  async fetch(req, env, ctx): Promise<Response> {
    const result = await env.SUM_SERVICE.sum(1, 2);
    return new Response(result.toString());
  }
} satisfies ExportedHandler<Env>;