Getting started

Nelo keeps application code on Web Standards and places Node transport behavior behind nelo/node.

Create an application

import { Nelo } from "nelo";
import { serve } from "nelo/node";

const app = new Nelo();

app.get("/", (context) => {
  return context.json({ message: "Hello from Nelo" });
});

const server = serve(app, {
  hostname: "127.0.0.1",
  port: 3000,
});

const address = await server.listen();
console.log(address);

Start owned work

context.fork() creates eager work owned by the current request. Pass the supplied signal into cancellable APIs.

app.get("/users/:id", async (context) => {
  const user = context.fork((signal) =>
    fetchUser(context.params.id, { signal })
  );

  return context.json(await user);
});

Register resources

context.use() binds cleanup to the handler lifetime and disposes resources in reverse acquisition order.

app.get("/report", async (context) => {
  const database = await openDatabase();
  context.use(() => database.close());

  return context.json(await createReport(database));
});

Close gracefully

await server.close({
  gracePeriod: 5_000,
  forceAfter: 10_000,
});

The server stops accepting new connections, waits during the grace period, propagates server_shutdown, and destroys remaining sockets only at the hard deadline.