Elide global

Elide is a global with build metadata and the serve() HTTP entry point.

Elide.serve(options)

Elide.serve takes a Fetch-style handler and returns an object with port, hostname, and close():

const server = Elide.serve({
  port: 3000,
  hostname: "127.0.0.1",
  fetch(request) {
    return new Response("hello");
  },
});

Without hostname, the server listens on every network interface and is reachable from other machines. Pass hostname: "127.0.0.1" to accept local connections only:

const open = Elide.serve({ fetch: () => new Response("ok") });
console.log(open.hostname, open.port);
open.close();

const local = Elide.serve({ hostname: "127.0.0.1", fetch: () => new Response("ok") });
console.log(local.hostname, local.port);
local.close();

0.0.0.0 36518
127.0.0.1 38424

• elide run does not exit until close() is called.
• Connections are accepted once the entry module, including top-level await, has finished. A request made from top-level code to the module’s own server waits forever; make it from a callback such as setTimeout.
• It serves HTTP/1.1, and HTTP/2 over TLS.
• Request and response bodies stream; return a Response backed by a ReadableStream to stream output.
• request.signal aborts when the client disconnects.
• Responses are sent as returned and never recompressed; set Content-Encoding and Vary: Accept-Encoding yourself.

HTTPS

import { readFileSync } from "node:fs";

const server = Elide.serve({
  hostname: "127.0.0.1",
  port: 8443,
  cert: readFileSync("cert.pem", "utf8"),
  key: readFileSync("key.pem", "utf8"),
  fetch: (request) => new Response(`hello over ${new URL(request.url).protocol}\n`),
});

curl -sk https://127.0.0.1:8443/
hello over https:

Request limits

const server = Elide.serve({
  hostname: "127.0.0.1",
  port: 0,
  maxBodyBytes: 1024,
  async fetch(request) {
    const body = await request.text();
    return new Response(`received ${body.length} bytes\n`);
  },
});

setTimeout(async () => {
  for (const size of [512, 4096]) {
    const res = await fetch(`http://127.0.0.1:${server.port}/`, { method: "POST", body: "x".repeat(size) });
    console.log(size, res.status, (await res.text()).trim());
  }
  server.close();
}, 0);

512 200 received 512 bytes
4096 413 Payload Too Large

Exported fetch handler

An entry ES module can default-export an object with a fetch(request) method instead:

export default {
  hostname: "127.0.0.1",
  port: 3000,
  fetch(request) {
    return new Response(new URL(request.url).pathname);
  },
};

• elide run, elide serve, and elide dev start it after the module, including top-level await, finishes.
• Imported modules never start a server.
• fetch is called with the exported object as this and returns a Response or a Promise of one.
• run binds the exported hostname and port, default 127.0.0.1:8080; --host and --port override them in serve and dev.

Samples

• Server-sent events
• Request limits
• Multi-context server